Archive | April 2017

Case 9: Community and ambulatory care issues in infection control

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The staff of your ambulatory care unit in a community-based hospital have asked you to meet with them regarding some specific issues they have as influenza season approaches.

Their concerns are as follows:
a) lack of separation between potentially infectious patients and non-infectious patients,
b) lack of facilities for adequate handwashing
c) concerns regarding side-effects of influenza vaccination and
d) whether vaccination of staff is compulsory and what will happen if staff choose not to be vaccinated.

You visit the area and note that there is a common waiting room, that rooms are usually used for multiple clinics during the week, and that there is indeed a lack of sinks. Further questioning reveals that approximately 30% of the staff are vaccinated for influenza yearly.

Case Nine Questions:
1. How would you mitigate against the risk of respiratory infections in the ambulatory care setting?

Promote good hand hygiene: Place hand sanitizer stations at the front door, admin/admissions desk and outside every clinic room (lautenbach, p. 397).

Educate:

  • Implement respiratory hygiene and cough etiquette: Post “cough etiquette” signs in the waiting room and washrooms along with hand sanitizer dispensers and tissues within easy reach(CDC, 2016).
  • Screening and triage of symptomatic patients: Ask any sick patient to phone ahead so that they may be re-scheduled and seen at the start or end of appointment days to prevent their sitting in the shared waiting room for extended periods (CDC, 2016). Note: if the patient’s appointment can be postponed until they are no longer sick, do so to avoid sick patients coming into the hospital at all. (CDC, 2016)
  • Instruct patients (and those accompany them) to inform staff upon arrival if they have symptoms of any respiratory infection (cough, runny nose, fever) and to take appropriate preventive actions (wear a facemask), (CDC, 2016).
  • Instruct sick patients (and educate staff triage patients) to report to the front desk upon arrival so that they may be shown into the next available clinic room rather than sitting out in the shared waiting room for long periods where they might infect others.
  • For clinic team leads “strong organizational leadership and an infrastructure for clear and timely communication and education, and for program implementation, have been common elements in successful programs.”(CDC, 2016)

Vaccinate:

  • Promote the flu vaccine and offer vaccination clinics to staff and vulnerable patients prior to the onset of flu season (Lautenbach, 397).
  • Also consider offering vaccination to vulnerable patients against preventable infectious diseases beyond the flu considering the shared environment in which different clinics are run(Lautenbach, p. 397).
  • The infection preventionist’s goal should be to vaccinate everyone who shares the community-based hosptial “unless contraindicated, vaccinate all people aged 6 months and older, including HCP, patients and residents of long-term care facilities” (CDC, 2016).

Use techniques to increase the flu vaccine rate amongst staff (we know currently on 30% are vaccinated).

Strategies such as:

  • providing incentives
  • providing vaccine at no cost to staff or vulnerable patients
  • improving access (e.g., offering vaccination at work and during work hours)
  • require staff and patients to sign a form to acknowledge that they have been educated about the benefits and risks of vaccination to be kept on file
  • mandating influenza vaccination for all healthcare professionals without contraindication is also an option (this seems to be debated every year!) (CDC, 2016).

Sanitization and cleaning:

  • Ensure proper adherence to environmental infection control procedures
  • ensure proper protocols are followed for sterilization and disinfection of all equipment
  • ensure high-touch surfaces in the environment are cleaned frequently throughout the clinic days
  • ensure proper cleaning procedures are followed for cleaning and disinfection of waiting room and clinic rooms as they are at higher risk to transfer infections being used for multiple clinics during a week (Lautenbach, p. 397).

Surveillance: perform surveillance for healthcare-associated infections at this community based hospital

  • Investigate any influenza outbreaks.
  • Ensure a mechanism of investigation and reporting of sentiel healthcare associated infection events is in place (Lautenbach, p. 398).
  • Sick staff: appropriate management of ill health care workers (use influenza screening tool for sick calls) (CDC, 2016).
  • Risk management: adherence to infection control precautions for all patient-care activities and aerosol-generating procedures (CDC, 2016)

Infection control precautions for staff to mitigate against the risk of respiratory infections:

  • wear gloves when in contact with any potentialy infectious material
  • gown for care activities with risk of contact with blood, body fluids, secretions (including respiratory), or excretions (CDC, 2016)
  • Remove gown and perform hand hygiene before leaving the patient’s environment.
  • Upon arrival, and until departure from the community-based hospital place patients on droplet precautions with suspected or confirmed influenza for 7 days after illness onset or until 24 hours after the resolution of fever and respiratory symptoms, whichever is longer (CDC, 2016).
  • Staff are to follow influenza patient care policy of putting on a mask prior to entering a room containing an influenza infected patient. (CDC, 2016).

Implement engineering controls:

  • Renovate the community-based hospital if possible to a design with control measures to reduce or eliminate exposure to infection
  • Install elements that shield staff and other patients from infected individuals
  • Examples of engineering controls include installing physical barriers such as partitions in triage areas and curtains that are drawn between patients (CDC, 2016).

Limit visitors:

“Visitors who have been in contact with the patient before and during hospitalization are a possible source of influenza for other patients, visitors, and staff”(CDC, 2016).

  • Restrict visitors to those necessary for the patient’s emotional well-being and care
  • Screening visitors for symptoms of acute respiratory illness over the phone before they accompany a patient to the community-based hospital
  • provide instruction (if possible before arrival) or at the front door using posters and signage on hand hygiene, limiting surfaces touched, and use of personal protective equipment (PPE) if needed.
  • Visitors should not be present during aerosol-generating procedures.
  • Visitors should be instructed to limit their movement within the facility (CDC, 2016).

2. Do you have any suggestions on how to involve the patients and family in infection control in this unit and in the community?

According to the public health agency of Canada, there are key elements to effiectively engaging the public. The 5 steps are:

  • Planning
  • Developing products
  • Implementing
  • Reporting
  • Evaluating (HC and PHAC, 2016)

Examples of engagement are:

  • Provide handwashing and cough etiquette material and posters for patients and families to read, share, put up in their community such as at their schools, local libraries, their workplaces and even in their homes.
  • Patients and families can help one another as well as other families and patients they come in contact with in this unit by following good flu prevention strategies.
  • They can get the seasonal vaccine, remind others to do so as well along with reminders to wash hands or cover their cough.
  • Families and patients both can help prevent the spread of the seasonal flu by staying home when sick.
  • Broadcast public education and information on social media, TV and radio (PH and PHAC, 2016).
  • Place flu prevention technique posters on buses, in public washrooms and publc waiting areas around town.

3. What is the current recommendation or directive from your province regarding vaccination of healthcare workers? Explain the rationale for the directive and why you agree or not.

The BCCDC influenza prevention policy states:

“BC’s Influenza Prevention Policy requires all healthcare workers to either be vaccinated against influenza or wear a mask in patient care areas throughout the influenza season. The policy also applies to visitors, volunteers and students who attend a patient care area” (BCCDC, 2017).

The rationale for the directive:

If less than the target of 80% of healthcare workers are immunized herd immunity falls below levels effective at preventing an influenza outbreak in a healthcare setting which places vulnerable patients at risk.

Healthcare workers are exposed to the most vulnerable individuals in a population – those at greatest risk for contracting the flu and suffering potentially life-threatening complications as a result of the flu. “Severe illness can result in hospitalization or death. Certain populations, such as young children and seniors, may be at higher risk for serious influenza complications such as viral pneumonia, secondary bacterial pneumonia and worsening of underlying medical conditions.” (PHAC, 2017).

If healthcare workers become sick with the flu they may spread it to vulnerable patients whom are unable to fight it off due to their underlying conditions.

Some patients may be immunocompromised as a result of their underlying conditions or as a result of treatment. These patients cannot build sufficient immunity against the flu even if a vaccine is given as therefore rely on (herd immunity) those around them being healthy (BCCDC, 2017).

Rationale according to the ministry of health:

  • “Influenza – or the flu – can be a serious contagious disease, which is spread by droplet transmission through close contact with an infected person. Infected individuals are highly contagious and can transmit the virus for 24 hours before they show any symptoms.”
  • Influenza causes by far the most deaths among vaccine- preventable diseases, outpacing all others combined.
  • Hospitalized patients and seniors in residential care are more vulnerable to influenza than healthy adults.
  • The vaccine is also less effective for frail seniors or other hospitalized patients, making it even more important that their caregivers are vaccinated.
  • Infected health care providers can pass the virus on to their patients before they even know they are sick. The most effective way to prevent the flu is by getting vaccinated” (Ministry of health, 2014).

4. What other respiratory illness might cause outbreaks in the community and the hospital setting? What rapid diagnostic methods are used to identify viral respiratory pathogens?

Respiratory illnesses that cause community outbreaks:

  • Severe acute respiratory syndrom (SARS)
  • Measles
  • Tuberculosis (TB) (Lautenbach, p. 357)

Other illnesses spread in outpatient settings:

  • Bordetella pertussis (Lautenbach, p. 361)
  • Varicella- zoster virus
  • parvovirus B19

Rapid diagnostic methods for viral respiratory pathogens:

New methods:

  • rapid respiratory virus culture methods
  • pooled antibody reagents
  • rapid antigen direct tests (RADTs)
  • improved specimen collection devices
  • nucleic acid amplification tests (NAATs).
  • “The introduction of these new systems has created new challenges for laboratory directors, who must decide which of the many tests to offer and what specimen types to accept for diagnostic testing”(Gnocchino and McAdam , 2011).

Old/Traditional methods:

  • RADTs
  • direct fluorescent antibody testing (DFA)
  • virus culture
  • traditional methods are often inferior in assay sensitivity, specificity, time to virus identification, and breadth of pathogen detection compared to NAATs. (Gnocchino and McAdam, 2011)

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(Above table from USCDC, 2016)

5. You decide they might benefit from a more structured infection control approach. What key elements are important to consider in an outpatient infection control program?

  • Patients maybe carrying unrecognized pathogens in and out of the outpatient envirmonment (Lautenbach, p. 357).
  • the appropriate level of infection prevention to prevent ambulatory care-associated pathogen transmission is presently unknown (Lautenbach, p. 357).
  • The CDC has not yet recommended specific infection prevention and control surveillance systems for ambulatory care (Lautenbach, 357).
  • Infection prevention and control programs, planning and resources are lften lacking beyond inpatient hospital settings.

Key elements of infection prevention and control for outpatient settings are:

Pathogen Transmission occurs in 2 ways:

  1. congregation of patients in waiting rooms/areas or common rooms/areas
  2. invasive procedure-associated

Pathogens can be spread via healthcare workers in these amublatory care settings when staff fail to follow proper:

  • aseptic technique
  • hand washing technique
  • environmental sanitation standards(Lautenbach, p. 357)

In structuring infection control in outpatient settins Infection Preventionists must determine:

  • which infections to conduct surveillance on
  • whom to report the data to
  • who will be responsible for implementing the changes (Lautenbach, p. 357).

Methods to reduce respiratory illness spread in outpatient settings:

  • post visual alerts at the entrance to instruct patients to report respiratory symptoms
  • cover nose and mouth when coughing or sneezing
  • use tissues to contain respiratory secretions and dispose of them in nearest garbage
  • perform hand hygiene after contact with respiratory secretions, contaminated objects or materials
  • provide conveniently located handwashing agents
  • offer masks to coughing persons
  • trage coughing persons out of the common areas asap (Lautenbach, 359).

References:

1. Lautenbach, E., Woeltje, K., and Malani, P. 2010. Practical HealthcareEpidemiology, 3rd ed.

2.  Center for disease control and prevention, CDC (2016). Prevention Strategies for Seasonal Influenza in Healthcare Settings Guidelines and Recommendations. https://www.cdc.gov/flu/professionals/infectioncontrol/healthcaresettings.htm

3. BCCDC. (2017). Influenza Prevention Policyhttp://www.bccdc.ca/health-professionals/clinical-resources/immunization/influenza-prevention-policy

4. Public Health Agency of Canada. (2017). Canadian Immunization Guide Chapter on Influenza and Statement on Seasonal Influenza Vaccine for 2016-2017. http://www.phac-aspc.gc.ca/naci-ccni/flu-2016-grippe-eng.php#i2

5. Ginocchio, C. C., & McAdam, A. J. (2011). Current Best Practices for Respiratory Virus Testing. Journal of Clinical Microbiology, 49(9 Suppl), S44–S48. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3185851/

6. Health Canada and the Public Health Agency of Canada. (2016). Guidelines on Public Engagement. Obtained from: http://www.healthycanadians.gc.ca/publications/health-system-systeme-sante/guidelines-public-engagement-publique-lignes-directrice/alt/pub-eng.pdf

7. USCDC. (2016). Rapid Diagnostic Testing for Influenza: Information for Health Care Professionals. https://www.cdc.gov/flu/professionals/diagnosis/rapidclin.htm#Table1

8. ministry of Health. (2014). Influenza Vaccine – Frequently Asked Questions Influenza Control Program. http://www.immunizebc.ca/sites/default/files/graphics/influenzavaccinefaqphsa.pdf

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Case 4: Antimicrobial resistance and infection control

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    The 600-bed tertiary adult care hospital where you work has had 46 patients with Methicillin Resistant Staphylococcus aureus (MRSA) in the past two months. Cases have occurred on the General Surgical Floor and this is a significant increase from the previous two months. You have implemented appropriate procedures and the situation appears to be under control. However, now you are asked to deal with issues regarding transfer of patients within your own institution, to long-term care facilities and to other acute care facilities. In particular, the long-term care institutions are reluctant to accept patients because of concerns regarding increased work-load and spread of “infection” to other residents.
    Case Four Questions:
    1. What are the specific mechanisms of resistance in MRSA, vancomycin resistant enterococcus (VRE) and carbapenem resistance in Gram Negative Bacilli?

Mechanism of resistance in MRSA
Resistance to methacillin in S. aureus is due to an alternate penicillin binding protein being produced called PBP2a (Lautenbach, P.198). This alternative penicillin binding protein has a low affinity for beta-lactam antibiotics. As a result the bacteria continues to be able to generate stable peptidogycan structures (that forms it’s cell wall) in the presence of formerly inhibitory concentrations of beta-lactam antibiotics (Lautenbach, P.198).

The gene that encodes for this resistance is located on the staphlococcus chromosome cassette mec, SCCmec. Transfer of the SCCmec gene from strain to strain has been rare and worldwide spread has been greatly due to clonal expansion of a few strains.
There are community acquired strains – SCCmec type IV
Multidrug resistant strains – CA-MRSA USA 300

Mechanism of resistance of Vancomycin resistant enterococcus (VRE)

Resistance to vancomycin in Enterococccus strains is for the most part due to acquiring either vanA or vanB genes (Lautenbach, P.199). These genes hold the DNA blueprint for the creation of the enzyme used to produce the precursors of peptidoglycan which then have reduced binding affinity for glycopeptides resulting in a weakened bacterial cell structure (Lautenbach, P.199). Resistance genes are carried on easily transferrable plasmids shared between strains.

Mechanism in Carbapenem resistance in Gram Negative Bacilli is the ”
carbapenemase genes, located on transferable plasmids” (picnet CPO toolkit, p.4)
These mechanisms of resistance cause outer-membrane protein deficiencies, result in carbapemase production and impact the efflux pumps (Lautenbach, P.211).

As to specific mechanisms of this resistance, in P. aeruginosa, imipenem resistance results when the OprD outer membrane protein that was accessible to carbapenems is lost. With P. aeruginosa, some efflux mechanisms reduce susceptibility to meropenem and doripenem (Lautenbach, P.212).

Carbapenem resistance in K. pneumonia is due to production of KPC, broad spectrum beta-lactamases which confer resistance to beta-lactams, beta-lactam-beta-lactamase inhibitor combinations and carbapenems. The enzyme that encodes this resistance is located on an easily transmissible plasmid (Lautenbach, P.213).
2. What procedures would you have implemented immediately to control this outbreak?

  • All infected patients would be placed on contact isolation (glove and gown) until until lab results return with no detectable MRSA colonization (PICNET, 2013, p. 17).
  • ensure staff and patients are compliant with hand hygiene (Lautenbach, p. 200)
  • ensure proper disinfection protocols are being followed for equipment and environment
  • staff education about MRSA
  • Implement an MRSA monitoring program (Lautenbach, p. 200)
  • continue to monitor MRSA case reporting and infection rates
  • conduct active surveillance testing for MRSA colonization among patients on the general surgery floor
  • provide decolonization therapy to MRSA colonized patients in conjunction with active surveillance testing program (Lautenbach, p. 200)

3. How will you address the long-term care institutions concerns and what evidence do you have to support your suggestions/recommendations?

For patients being transferred from hospital to a long term care facility, the sending unit will provide ARO status in their transfer report to the receiving facility. The facility can then take steps to ensure proper infection control measures are in place if needed and that further treatment can be continued if needed. “Admission should not be denied or delayed by a RCF on the basis of colonization or infection with an ARO. If a resident is known to be colonized with an ARO, it should be included in their health history and documentation, as this information may guide antibiotic or other treatment choices and is required should they require admission to acute care” (picnet ARO toolkit, p. 13).

Screening should be done following this outbreak and prior to transfer for high risk patients or those who had close contact with an ARO patient and were potentially exposed to MRSA on the general surgery floor (picnet ARO toolkit, p. 14).

The receiving care facility would perform a transmission risk assessment
“Patients at increased risk of disseminating MRSA include:
individuals with colonized tracheostomy and uncontrolled respiratory secretions

individuals with respiratory infections

individuals with wound or stoma drainage that is not contained by a dressing or appliance

individuals with desquamating skin conditions (e.g. psoriasis, burn patients)

individuals who are cognitively impaired (unable to comply with instructions)

individuals who have poor hygiene and are non-compliant with instructions. ” (picnet ARO toolkit, p. 15).

The facility would use the transmission risk assessment to determine what precautions are necessary as they await the return of MRSA swab results.

For admission to long term care of MRSA colonized patients contact precautions should be implemented and this will help prevent transmission to other patients in the facility(picnet ARO toolkit, p. 16).

The following precautions should be followed:

“gloves upon entering the room or patients bed space for any contact with patient or their environment

gowns when providing care to patient or if skin or clothing may come in to contact with their environment

if possible, dedicate any equipment (e.g. blood pressure cuff, stethoscope) to that patient; otherwise, clean and disinfect with a hospital-grade disinfectant prior to using with another patient.

Gloves and gowns must be removed and hands cleaned upon leaving the room or patient’s bed space.

Routine practices recommend the use of a mask when caring for individuals who have a febrile

respiratory illness. As well, a small number of studies support the use of a fluid-resistant mask when

caring for a patient who has respiratory symptoms or a tracheostomy, and has MRSA identified in their sputum ” (picnet ARO toolkit, p. 17).
4. Your facility has decided that a hand hygiene program could be effective in decreasing MSRA. Briefly list and discuss key elements of a hand hygiene program.

Key elements of a hand hygiene program:

  1. System change: make it possible, easy and convenient – sinks and products such as alcohol based hand rub in reach
  2. Hand hygiene education: Knowledge of hand hygiene guidelines, transmissible diseases spread by lack of hand hygiene etc
  3. Promote/faciliate hand washing and skin care for healthcare worker’s hands
  4. Routine observation and feedback: Audits of hand hygiene practices and performance feedback
  5. Reminders in the workplace: posters at sinks, outside clinic rooms etc
  6. Improve institutional safety climate: involvement from individual and institutional levels, ensure adequate staffing, institutional rewards, empower patients to ask/remind staff and involve them to perform good hand hygiene themselves
  7. Combine several of the above factors(WHO, 2009, p96).

5. Currently there is controversy regarding whether infection prevention should primarily employ a “vertical” versus a “horizontal” approach to ARO management or a combination of both. Please state what your position is and why.

We are currently using a combination of both vertical and horizontal approaches to ARO management after noting the examples of both in the table in the Goldmann et al article

Vertical approaches reduce risk of infections due to specific pathogens:

  • Active surveillance testing to identify asymptomatic carriers
  • Contact precautions for patients colonized or infected with specific organisms
  • Decolonization of patients colonized or infected with specific organisms

Horizontal approaches reduce risk of a broad range of infections and are not pathogen specific:

  • Standard precautions (eg, hand hygiene)
  • Universal use of gloves or gloves and gowns
  • Universal decolonization (eg, chlorhexidine gluconate bathing)
  • Antimicrobial stewardship
  • Environmental cleaning and disinfection” (Goldmann et al, p798).

“applying other evidence-based, horizontal strategies such as universal decolonization in settings where benefits are likely to outweigh risks and costs; and …using AST and other vertical approaches selectively when epidemiologically important pathogens are newly emerging and rare to a given institution or region or to control out- breaks of specific pathogens.”(Goldmann et al, p798).

References:

1. Lautenbach, E., Woeltje, K., and Malani, P. 2010. Practical HealthcareEpidemiology, 3rd ed.

2. World Health Organization. WHO guidelines on hand hygiene in health care. Geneva; 2009. http://apps.who.int/iris/bitstream/10665/44102/1/9789241597906_eng.pdf

3. Goldmann, Donald A., Perl, Trish M., Septimus, Edward., Weinstein, Robert A., and Yokoe, Deborah S. (2014). Infection Control and Hospital Epidemiology. http://www.jstor.org/stable/pdf/10.1086/676535.pdf

Case 3: Nosocomial infections and Surveillance/Outbreak Investigations

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Upon reviewing the monthly statistics for C.difficile in your facility you note that there are seven cases of C.difficile associated disease (CDAD) on the gastrointestinal surgery floor in the past three weeks. You decide to investigate further and find that these are, indeed, laboratory confirmed cases and that all of them have been acquired in-hospital The number of cases is above the usual baseline for this ward.
Case Three Questions:
1. Describe the steps you would take to immediately investigate and control this outbreak.

“Epidemic associated infections often are clustered temporary or geographically suggesting that infections are from a common source (e.g. contaminated equipment or devices), …secondary to person-person transmission” (Lautenbach p. 143). With this in mind my immediate steps to control the outbreak would be to:

steps to control the outbreak
Step1. ensure all patients with confirmed cases of C.Difficile are on contact isolation precautions and those with suspected C. Difficile are tested (c.diff tool kit PDF) .

Step 2. I would implement a gastrointestinal illness algorithm “to immediately identify and implement Contact Precautions for patients with acute onset diarrhea” (c.diff tool kit PDF) and ensure stool samples are tested for this patient group and that contact precautions remain in place for the duration of diarrhea, then 48-72hrs after stools normalize(c.diff tool kit, p.8).

Step 3. Implement “A transmission risk assessment of each patient” (c.diff tool kit, p.8) to determine if further precautions required.
Step 4. Implement an infection control sheet for documentation in the chart that indicates when precautions are initiated and when they are discontinued along with a stool chart.

Step 4. Provide ongoing staff, patient and visitor education re: hand hygiene and infection prevention precautions

Patients with C.diff should be in a single room when possible, in shared room with other c.diff patients (each under contact precautions with their own personal commodes or if that is not possible, ensure the contact precautions in place for the patient’s bed space and immediate surroundings. ( c.diff tool kit PDF).

Special note: Deciding whether or not to close the gastrointestinal surgery floor would be based on “the severity of the illness, the size of the outbreak and the rate at which new cases are occurring” (Lautenbach p. 149). Deciding whether to limit new admissions to the floor would occur in consult “with the MHO, or designate for the management of outbreaks by IPC and the facility administrator is required under the public health act” (c.diff tool kit PDF)

I would then contact the lab to save all specimen “isolates that might be part of the outbreak” for C. diff strain comparison and outbreak source tracing (Lautenbach p. 145).

Steps to investigate the outbreak
The immediate steps I would take to investigate the outbreak would be to

Step1. test all patients on the unit and test rooms that had contained a C.diff treated patient after discharge and before new admission to ensure that current sterilization/cleaning measures are adequate so that the room and surfaces within it are not C.diff reservoirs.

Step2. Continue trace infection source or reservoir. Consider the OR if needed and lab test the OR and surgical equipment to ensure the equipment or OR itself is not the disease vector for transmitting the C. difficile. “Contamination of environmental surfaces along with lapses in infection control precautions…have been implicated repeatedly in outbreaks of…C.difficile” (Lautenbach p. 145).

Step3. Implement cleaning schedule and review cleaning practices such as the use of sporicidal cleaning agents. Ensure surfaces frequently touched by patients are cleaned twice daily (c.diff PDF, p8)

Step 4. Implement a discharge/transfer cleaning audit too.

In the event that the outbreak is traced back to a single patient, following up with public health may help prevent the spread in community. In the event the outbreak is traced back to equipment (surgical equipment not being able to be effectively sterilized), following up with the manufacturer may help prevent similar outbreaks in other institutions using the same devices.

Special note: Conducting an epidemiologic study would be a step (being mindful of resources) if there is “need to convince clinical staff that the proposed source or mechanism (of disease spread) suggested by chart reviews and observations is correct” and lab testing was unable to trace outbreak back to source.
2. Provide a case definition for this outbreak and provide the rationale for your answer.

A case definition states which individuals have symptoms or findings and specifies the time period: the time the symptoms began, were recognized and specifies the location associated with the onset of symptoms (lautenbach, p146). In this case the case definitions includes the seven patients on the gastrointestinal surgery floor who have laboratory confirmed cases of C. difficle over the last three week period. Our case definition is based on the laboratory confirmed data however this case definition may widen or narrow depending on the results of the investigation and the discovery of the final source of infection (infection reservoir). “How broad or narrow to make the case definition often depends on the frequency with which the organism or condition is encountered”(Lautenbach, p.146). At present our case definition has not expanded outside the GI surgery floor’s 7 confirmed cases

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3. Staff are concerned about their risk for acquiring C.difficile. What is your response?

Staff should place C. diff infected patients on contact precautions to prevent transmission. Staff should glove and gown upon entering infected patients’ rooms or patient area. (PICNet, 2012).

Staff should follow good hand hygiene practices before and after patient contact. Soap and water is more effective than alcohol base handrub against C. Diff (Picnet, 2012, p. 6).

Staff should maintain patients on contact preautions for 48-72 hours after stools normalize (Picnet, 2012, p. 7)

Few staff will have risk factors for acquiring C. Diff. Risk factors for C. Diff are:

  • age over 65 years
  • prior hospitalizations
  • increased length of stay in an intensive care unit, ICU
  • nonsurgical admission to the hospital
  • exposure to broad spectrum antimicrobials
  • longer duration of antimicrobial use
  • exposure to multiple antimicrobials
  • exposure to acid supressive therapy
  • cancer chemotherapy
  • renal insufficiency
  • hemodialysis
  • nasogastric tube in-situ

4. Staff are also concerned that alcohol handrub may not be adequate. What is your reply?

Alcohol based hand rubs do not kill C. diff spores so hand washing with soap and water is necessary. (Lautenbach, p.224).
5. You decide to implement a system for monitoring the quality of cleaning. What types of monitoring might you consider and why? What are some of the newer adjunctive technologies to cleaning and disinfection of surfaces and equipment.

  • Develop a schedule to regularly review and evaluate all cleaning practices by an individual external to the unit. (PicNET, 2012, p.7 ).
  • Use sporicidal agents to address environmental contamination in areas associated with increased rates of CDI such as Sodium hypochlorite 1000 ppm – 5000 ppm and Hydrogen peroxide enhanced action formulation (PicNET, 2012, p.7)
  • UV light
  • Physical cleaning of surfaces is required in order to reduce the bioburden.
  • ensure pre-cleaning to reduce bioburden occurs before sporocidal cleaning
  • Insigate twice daily cleaning of frequently touched surfaces in the patient’s bed space and bathroom (Picnet, 2012, p8)
  • put in place a discharge/transfer cleaning audit tool for room cleaning when the patient is removed from Contact Precautions as well as upon transfer/discharge.

References:

1. Lautenbach, E., Woeltje, K., and Malani, P. 2010. Practical HealthcareEpidemiology, 3rd ed.

2.  Provincial Infection Control Network of British Columbia: PICNet BC Clostridium difficile infection toolkit and clinical management algorithm at https://www.picnet.ca/wp-content/uploads/Toolkit-for-Management-of-CDI-in-Acute-Care-Settings-2013.pdf.

Case 2: Infection Control Precautions

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The paediatric ward informs you of a child admitted last night with a maculopapular rash. The child is currently in a single room; however, the staff are requesting you review the type of infection control precautions required. There is no history of contact with measles, mumps or rubella, however, the child has never been immunized. Clinically the child has a dry cough, coryza and a pink maculopapular rash – the parents are unsure of where the rash started. The paediatrician suspects measles or rubella.
Case Two Questions:
1. What are your recommendations regarding infection control precautions for this child?

Suspected measles=airborne precations.

Patients with suspected measles should be placed under airborne precautions (Lautenbach, p. 57).

Airborne precautions “prevent disease transmission by aerosols containing droplet nuclei or contaminated dust particles” (Lautenbach, p. 57). Droplet nuclei are less than 5um in size and may remain suspended in the air allowing them to migrate for long periods of time.

The patient is already in a private room but should be in an airborne infection isolation room, AIIR, which is a private room with negative air pressure and at least 6 air exchanges per hour (preferrably 12). Room air being exhausted directly outside or through a high efficiency particulate air, HEPA, filter. The room door should be kept closed at all times. (Lautenbach, p. 57).

Patient transport: a surgical mask should be worn by the patient.

Visitors and staff entering the room: wear a respirator. The N95 mask filters out 95% or particles.

Suspected rubella=droplet precautions

Droplet precautions “prevent the transmission of micro-organisms by particles larger than 5um. Droplets are produced when the patient talks, coughs, or sneezes. (Lautenbach, p.58.)

The patient should also be placed on contact precautions to prevent spread of disease from contaminated surfaces (Lautenbach, p. 59). Measels mode of transmission is through “airborne by aerosol and droplet spread, direct contact with nasal or throat secretions of infected persons; less commonly by articles freshly soiled with nose and throat secretions.” (BCCDC, 2014). Healthcare workers should gown and glove when entering the room and change gloves if touching materials with high concentration of micro-organisms.

Considering the patient has a rash that is not yet known to be rubella or measles it is best to place the patient in the more extensive and encompassing precautions – airborne isolation with contact precautions until a definite diagnosis can be made (Lautenbach, p. 59).

Once definitive diangosis is made, isolation precaution continuation and removal will follow CDC guidelines for the pathogen-specific illness (Lautenbach, p. 59).
2. What laboratory tests would help in the diagnosis and why is it important to confirm your suspicions?

Lab tests for measels:

  • Submit a nasopharyngeal swab and urine sample for measles virus isolation and PCR testing.
  • isolation of measles virus from an appropriate clinical specimen
  • detection of measles virus RNA
  • seroconversion or a significant (e.g. fourfold or greater) rise in measles IgG titre by any standard serologic assay between acute and convalescent sera
  • positive serologic test for measles IgM antibody using a recommended assay in a person who is either epidemiologically linked to a laboratory-confirmed case or has recently travelled to an area of known measles activity.
  • Epidemiologically-linked: • Clinical illness (fever≥ 38.3oC and cough, coryza or conjunctivitis and generalized maculopapular rash for at least 3 days) in a person with an epidemiologic link to a laboratory-confirmed case. (BCCDC, 2014)

Lab tests for rubella:

  • “Nasopharyngeal or throat swab specimens and/ or urine should be taken for virus isolation. Virus may be isolated 1 week before to 2 weeks after rash onset” (BCCDC, 2014)
  • isolation of rubella virus from an appropriate clinical specimen
  • detection of rubella virus RNA
  • seroconversion or a significant (i.e., fourfold or greater) rise in rubella IgG titre by any standard serologic assay between acute and convalescent sera
  • detection of rubella IgM antibody using a recommended assay in a person with an epidemiologic link to a laboratory- confirmed case or who has recently travelled to an area of known rubella activity
  • Epidemiologically-linked: Clinical illness (fever and rash, and at least one of the following: arthralgia/arthritis, lymphadenopathy, conjunctivitis) in a person with an epidemiologic link to a laboratory confirmed case (BCCDC, 2014)

Importance of confirming suspicions:

Due to infectious nature of disease, morbidity and mortality confirming cases promplty is of great importance. “Investigate all confirmed, probable, and suspect cases of measles within 24 hours”. For rubella “Confirming the diagnosis is particularly important in pregnant women, cases who have contact with pregnant women, suspected cases of CRS, and during outbreaks.” (BCCDC, 2014) as the virus has significant implications on the developing fetus.

Case reporting to the following is necessary along with contact tracing for tratment and containment of the outbreak.

  • Complete the individual case report in iPHIS (Integrated Public Health Information System)/ Panorama or PARIS.
  • Public health action, including contact management, may commence at any level of the case definition, including for a suspect case.
  • Inform the local Medical Health Officer and initiate control measures immediately.” (BCCDC, 2014)
  • Viral detection methods (e.g., RT-PCR followed by sequencing) enable a definitive diagnosis, allow the laboratory to distinguish vaccine virus type from wild virus type
  • DNA viral testing can determine if there are single or multiple genotypes of virus circulating in a community.
  • Genotyping of the virus is helpful in understanding transmission patterns
  • Genotying faciliates outbreak investigation when there is no epidemiological links between cases because such results can indicate whether the origin of the virus is the same or different. (CDC, 2014)
  • “Clinical diagnosis of rubella is challenging and may be inaccurate because symptoms and signs are not unique to this disease. ” (BCCDC, 2014). The virus has significant implications on the developing fetus therefore confirming a case is crucial for the pregnant woman and her GP to make informed decisions regarding pregancy care and carrying the fetus to term (BCCDC, 2014)

3. How would you perform a risk assessment to determine the extent of contact tracing for possible exposed individuals?

Risk Assessment: “An evaluation of the interaction of the health care provider, the client/patient/resident and the client/patient/resident environment to assess and analyze the potential for exposure to infectious disease.” (PIDAC pdf, p12)

“The risk of transmission of microorganisms between individuals involves factors related to:
 the client/patient/resident infection status (including colonization)

 the characteristics of the client/patient/resident

 the type of care activities to be performed

 the resources available for control

 the health care provider immune status.” (PIDAC pdf p.24)
I would start by determine if correct PPE was used and protocols followed as soon as measles or rubella was suspected. Determine at first encounter, if any staff were not yet following appropriate precautions (this would be prior to suspicion of rubella or measles). Consider all unimmunized staff, patients, and visitors waiting in ER, hallways, elevators at the time this patient was brought in and then transferred to the paediatric unit. Then all unimmunized hospital staff, patients, visitors within this suspected infected patient’s air space prior to the patient being place place in a negative pressure room and under correct isolation precautions for rubella/measles. (PIDAC pdf, p40)

Contact tracing would then extend beyond the hospital into the community (the child’s school, church, community/rec centre, library etc) for all unimmunized potentially exposed individuals – ensure these individuals get tested to contain outbreak.

Post exposure follow-up:
“ identification of exposed staff
 assessment and immunization history

 post-exposure prophylaxis and follow-up including:

 collection and analysis of exposures

 a program for prompt response to sharps injuries16, 77

 policies to deal with spills and staff exposure to blood or body fluids

 education regarding preventive actions that may be put into place to improve practices and prevent recurrence.” (PIDAC pdf, p64)
4. What is the difference between Airborne and Droplet Precautions? What is a bioaerosol?

Airborne Precautions “prevents disease transmission via aerosols containing droplet nuclei or contaminated dust particles.” (Lautenbach p. 57.) Droplet nuclei are particles less than 5um and may remaining suspended in the air for long periods. Airborne precautions therefore consist of a negative pressure, single patient room with at least air exchanges per hour exhausted to the outside or through HEPA filters and room doors must be closed. N95 or portable respirators must be worn by those entering the room and the patient must wear a surgical mask on transport outside the room. (Lautenbach, P57, Table 6-3)

Droplet precautions “prevent the transmission of microorganisms by particles larger than 5um”, produced when the patient talks, coughs or sneezes or during certain procedures. (Lautenbach p. 58) Droplet precautions consist of a single patient room where the door may remain open. Surgical or isolation mask must be worn by those entering the room and the patient must wear a surgical or isolation mask if transported outside the room. (Lautenbach, P57, Table 6-3

Bioaerosols: are “Small droplet of moisture that may carry microorganisms. Aerosols may be light enough to remain suspended in the air for short periods of time, allowing inhalation of the microorganism.” (PIDAC, p. vii)
5. You are asked to provide an education session to the staff on Infection Control Precautions. What principles would you use in your approach to planning and carrying out the session?

Adults learn best when convinced of the need for knowing the information. Often a life experience or situation stimulates the motivation to learn” (medscape article)

Therefore provide relevance, emphasizes how what the group is learning will help protect them as well as their patients.

“former experiences can assist the adult to connect the current learning experience to something learned in the past. ” (Russel, 2011).
Draw on the group’s experiences, have them give examples of past cases they have used various infection control methods relevant to this suspected measles/rubella case. Eg. Have any of them cared for a patient in a negative pressure room? When was the last time they cared for a patients under droplet precautions?

Facilitate the learning group process:

“The learner participates completely in the learning process and has control over its nature and direction.

It is primarily based upon direct confrontation with practical, social, or personal problems.

Self-evaluation is the principal method of assessing the progress or success.” (Medscape article)

Engage the group with a practically relevant trial runs by having them set up an infection control room for droplet precautions, a negative pressure room etc. have them volunteer ideas and critique the scenarios.

Understand there are different learning styles amongst the group: kinaesthetic, auditory and visual. Teach to all these styles. Provide hands-on activities such as the scenarios above for the kinaesthetic learners, use the visual aides (infection control signs/posters with steps on) for the visual learners and discuss material with repetitions during the session for the auditory learners. (Russel, 2011).

References:

1. Lautenbach, E., Woeltje, K., and Malani, P. 2010. Practical HealthcareEpidemiology, 3rd ed.

2. BCCDC. (2014). Communicable Disease Control Manual Chapter 1 – Management of Specific Diseases Measles. Section 6.1 Laboratory Testing. http://www.bccdc.ca/resource-gallery/Documents/Guidelines and Forms/Guidelines and Manuals/Epid/CD Manual/Chapter 1 – CDC/MeaslesSeptember2014.pdf

3. BCCDC. (2014). Communicable Disease Control Manual Chapter 1 – Management of Specific Diseases Rubella. Section 6.1 Laboratory Testing. http://www.bccdc.ca/resource-gallery/Documents/Guidelines and Forms/Guidelines and Manuals/Epid/CD Manual/Chapter 1 – CDC/RubellaSeptember2014.pdf

4. Provincial infectious diseases advisory committee (PIDAC). (2012). Routine practices and additional precautions in healthcare settings. http://www.publichealthontario.ca/en/eRepository/RPAP_All_HealthCare_Settings_Eng2012.pdf

5. Russell, SS. (2011). An overview of adult learning processes. http://www.medscape.com/viewarticle/547417_print

Final exam reference list

image

Textbook

  • Lautenbach, E., Woeltje, K., and Malani, P. 2010. Practical HealthcareEpidemiology, 3rd ed.
  • Airborne precautions – p. 57
  • Droplet and contact precautions – p.58
  • Common virus work ups – chicken pox, MMR, paro, Hep A, flu, TB – p. 292

Infection control structure and activities:

Weekly schedule and activities of an infection control professional

Measles

  • BCCDC. (2014). Communicable Disease Control Manual Chapter 1 – Management of Specific Diseases Measles. Section 6.1 Laboratory Testing. http://www.bccdc.ca/resource-gallery/Documents/Guidelines and Forms/Guidelines and Manuals/Epid/CD Manual/Chapter 1 – CDC/MeaslesSeptember2014.pdf

Rubella

  • BCCDC. (2014). Communicable Disease Control Manual Chapter 1 – Management of Specific Diseases Rubella. Section 6.1 Laboratory Testing. http://www.bccdc.ca/resource-gallery/Documents/Guidelines and Forms/Guidelines and Manuals/Epid/CD Manual/Chapter 1 – CDC/RubellaSeptember2014.pdf

Staff teaching/learning

  • Russell, SS. (2011). An overview of adult learning processes.  www.medscape.com/viewarticle/547417_print

Risk assessment

Provincial infectious diseases advisory committee (PIDAC). (2012). Routine practices and additional precautions in healthcare settings.

http://www.publichealthontario.ca/en/eRepository/RPAP_All_HealthCare_Settings_Eng2012.pdf

P.7

Outbreak Investigation: Lautenbach ch. 12 p. 145.

C. diff

  • Provincial Infection Control Network of British Columbia. (2012).  PICNet BC Clostridium difficile infection toolkit and clinical management algorithm. https://www.picnet.ca/wp-content/uploads/Toolkit-for-Management-of-CDI-in-Acute-Care-Settings-2013.pdf
  • Lautenbach ch19, p. 220

outbreak definition: sets the parameters or conditions for when an outbreak is declared. Includes person, place and time as it defines those individuals who will be counted as a case.

Antimicrobial resistance:

1. in the text:

  • Chapter 9 “Molecular Typing Systems”
  • Chapter 17 “Control of Gram-Positive Multidrug-Resistant Pathogens” p. 197
  • Chapter 18 “Control of Antibiotic-Resistant Gram-Negative Pathogens”
  • Chapter 19 “Clostridium difficile Infection” in the Lautenbach textbook.

2. PICNet BC. (2014). PICNet BC Toolkit for the Management of Carbapenemase producing Organisms (CPO) at https://www.picnet.ca/wp-content/uploads/PICNet-CPO-Toolkit-2015.pdf.

3. PICNet. (2013). Antibiotic Resistant Organisms Prevention and Control Guidelines for Healthcare Facilities. Retrieved from: https://www.picnet.ca/wp-content/uploads/PICNet_ARO_Guidelines_March2013.pdf

Various infection control guidelines PICNET: https://www.picnet.ca/guidelines/

Respiratory infections:

PICNet. (2011). Respiratory Infection Outbreak Guidelines for Healthcare Facilities. https://www.picnet.ca/guidelines/

Ambulatory care settings

  •  Chapter 27 “Infection Control in the Outpatient Setting” – p. 392
  • Chapter 23 “Exposure Workups”  – p. 291

Influenza:

hand hygiene:

World Health Organization. WHO guidelines on hand hygiene in health care. Geneva; 2009. http://apps.who.int/iris/bitstream/10665/44102/1/9789241597906_eng.pdf

Vertical and Horizonal approaches to  ARO management:

Goldmann, Donald A., Perl, Trish M., Septimus, Edward., Weinstein, Robert A., and Yokoe, Deborah S. (2014). Infection Control and Hospital Epidemiology. http://www.jstor.org/stable/pdf/10.1086/676535.pdf

Public engagement:

Health Canada and the Public Health Agency of Canada. (2016). Guidelines on Public Engagement. Obtained from: http://www.healthycanadians.gc.ca/publications/health-system-systeme-sante/guidelines-public-engagement-publique-lignes-directrice/alt/pub-eng.pdf

Human Factors engineering:

Employee Health and Occupational Medicine – text ch24, p. 319

Needle stick injury:

BCCDC. (2016). Blood and Body Fluid Exposure Management. http://www.bccdc.ca/resource-gallery/Documents/Guidelines%20and%20Forms/Guidelines%20and%20Manuals/Epid/CD%20Manual/Chapter%201%20-%20CDC/CPS_CDManual_BBFExpManage.pdf

Sharps injury prevention

CDC. (2008). Workbook for designing, implementing and evaluating a sharps injury prevention program. https://www.cdc.gov/sharpssafety/pdf/sharpsworkbook_2008.pdf

Contruction and renovation:

  • Chapter 34 “Infection Control Issues in Construction and Renovation” in Lautenbach. p. 439
  • Public health Agency of Canada. (2001). Construction-related Nosocomial Infections in Patients in Health Care Facilities. http://www.collectionscanada.gc.ca/webarchives/20071124025823/http://www.phac-aspc.gc.ca/publicat/ccdr-rmtc/01vol27/27s2/index.html
  • PICNet. (2012). Orientation program for Iinfection Control Professionals Module 10 “Construction and Renovation”.  https://www.picnet.ca/wp-content/uploads/10-Construction-Renovation.pdf

Chicken pox:

Case 1: Infection Control Structure

image

You are the infection control practitioner in a new, 400 bed community hospital with a six-bed adult and a six-bed paediatric intensive care unit. You have been asked to assist in establishing an Infection Control program and deciding its priorities.
Case One Questions:
1. What will be the structure of your infection control program? To whom do you think the program should report and why?

The structure should be in the form of a committee (Lautenbach, p. 403) with committee memebers holding hospital leadership positions which will enable them to provide insight, opinions and affect necessary change.

The infection control comittee should report to the facility’s medical board or medical advisory committee and/or senior management (Lautenbach, p 403).

Infection control committees composed of 8-12 members serve a single health care facility such as a hospital or long term care facility. Infection control committees composed of 15-25 members serve a health care region. (Lautenbach, p. 403)

An infection control committee is multidisciplinary with representatives from senior faclity management, the physcian group and nursing. Members from crital care, the surgical department, general medicine, the microbiology lab, pharmacy, occupational health, central processing, housekeeping and the local public health department should also be included (Lautenbach, p. 403).

The infection control program should report to their chair. The committee chair should be a physican leader for greatest effect. in best case scenario the chair is the hospital epidemiologist. With the committee reporting to a physician lead and hopefully a physician epidemiologist team lead, the infection control program is best supported to gain access to resources needed and to perform as efficiently as possible without being blogged down by leaders who do not fully understand the immplications of unmanaged infection control issues.
2. List key activities of your infection control program. Would these activities change if you were based in a long-term care institution? Why or why not?

  • hand hygiene audits
  • outbreak management: Acute event response, including outbreak investigation
  • staff and patient education
  • staff disease prevention/vacciation clinics
  • review of ongoing infection control measures
  • Surveillance
  • Performance improvement to reduce HAI
  • Reporting of HAI to the Centers for Disease Control and Prevention’s National Healthcare Safety Network as well as entities required by law (Bryant et al, 2016)

In long term care less acute issues arise, patient turnover decreased. The majority of staff are less educated therefore increased staff education and hand hygiene audits so that principals do not get overlooked due to “home -like” or more casual setting.
3. Using a table, outline your idea of a typical week for an infection control practitioner (you do not have to account for every hour of the day, but rather blocks of time or percentage of time dedicated to activities). Briefly discuss the rationale behind your time allotments.

Monday: 30% walk through of work area assigned/30% site surveillance/30% review isolation cases

Tuesday: 30% Staff education/ 30% walk through of work area assigned/30% review isolation cases

Wednesday: 30% walk through of work area assigned/30% site surveillance/30% review isolation cases

Thursday: 30% hand hygiene audits/ 30% review staff vaccination programs/ 30% site surveillance

Friday: 30% walk through of work area assigned/30% site surveillance/30% review isolation cases. (Archer, 2012).

Reviewing patients on isolation is essiential to infection prevention and control therefore should be given priority each day to stay on top of new cases. Educating staff and ensuring appropate precautions are being followed is also central to the role yet can be addressed through regular site surveillances and key components of education can be re-itterated once weekly with addition sessions as needed.
4. Would the percentage of time spent during your work week change if you were in a long-term care institution. Why or why not?

Yes it would change. LTC is less acute, less patient turnover, therefore more time could be spent on staff education, hand hygiene audits and surveillance than reviewing infection control and isolation cases as there would be fewer.
5. Where do you think Infection Prevention and Control should ‘fit’ operationally in relation to the Quality and Safety Program in a hospital?

Infection control should fit under epidemiology and within the hospital administration framework along with hospital quality management department, “care-managed entities, regulatory and accrediting agencies, lawmakers and public accountability “(Lautenbach, p. 43). Infection control must fit into this framework because “multidisciplinary collaborations are essential to instigate innovative preventative research, identify new applications for old prevention strategies, maximize synergy among the broad array of professionals engated in quality promotion effortsm minimize overlap and conserve scarse resources” (Lautenbach, p. 43)
6. What is the institutional role of Infection Prevention and Control in terms of Quality and Patient Safety initiatives?

“Healthcare-associated infections are an important measure or quality” (Lautenbach, p. 42). Hospital epidemiology and infection prevention and control must demonstrate compliance with evidence based standards and reduce incidence of nosocomial infections. With that comes insitutional pressure for infection, prevention and control teams to be clearly accountable to Quality and Patient safety. (Lautenbach, p. 42)

References:

1. Lautenbach, E., Woeltje, K., and Malani, P. 2010. Practical HealthcareEpidemiology, 3rd ed.

2. Kristina A. Bryant, Anthony D. Harris, Carolyn V. Gould, Eve Humphreys, Tammy Lundstrom, Denise M. Murphy, Russell Olmsted, Shannon Oriola and Danielle Zerr (2016). Necessary Infrastructure of Infection Prevention and Healthcare Epidemiology Programs: A Review. Infection Control & Hospital Epidemiology. https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0899823X15003335

3. Archer, Joanne. (2012). Orientation Program for Infection control professionals. https://www.picnet.ca/wp-content/uploads/01-Introduction.pdf

Case 8: Tuberculosis

One of the patients in your long-term care facility has a positive smear for Acid Fast Bacilli from a sputum sample. This gentleman resides in a four-bed ward and has been actively coughing blood-tinged sputum for the last two weeks following what appeared to be a flu-like illness. He is of Chinese descent and his family states that he has never been known to be exposed to tuberculosis. A rapid diagnostic test is done which confirms that the organism is indeed M.tuberculosisimageimage

Case Eight Questions:

1. How is the diagnosis of active tuberculosis made? Compare and contrast traditional culture methods versus newer rapid tests.

Diagnosis of active TB may be made with the use of “acid-fast bacilli on smear microscopy and/or culture of Mycobacterium tuberculosis, or…amplification and detection of M. tuberculosis complex (MTBC) nucleic acids using nucleic acid amplification tests (NAATs).” (Public Health Agency of Canada, PHAC, 2013).

Traditionally a chest X-ray was used in a TB diagnosis however an X-ray alone cannot provide conclusive diagnosis. Currently, a microbiologic testing is needed for conclusive diagnosis (PHAC, 2013).

In addition to NAAT, microscopic smear, and M. tuberculosis bacterial culture (in liquid and solid media), sputum samples should be collected. Minimum 3 samples collected a minimum 1 hour apart are needed (PHAC, 2013). If TB is suspected, three fluorescent smears should be tested. In new TB patients (with positive smear test) should have at least one respiratory specimen tested with a public health agency validated or approved NAAT (PHAC, 2013).

Traditional culture vs newer rapid testing:

Chest X-ray – has a sensitivity of only 70% – 80% for the diagnosis of active TB based on abnormal presentations and only 10% of HIV infected patients will score positive TB chest X-rays (PHAC, 2013).

Acid fast bacilli on smear microscopy – The most widely used rapid test.

The benefits of smear microscopy:

  • inexpensive
  • identifies the most infectious TB patients

The draw backs of smear microscopy:

• Sensitivity is modest and variable (20%-80%) depending upon the type of specimen, patient population, stain used and the experience of the microscopist. Thus, multiple sputum smears are recommended to increase the overall sensitivity and yield. Sensitivity is higher for respiratory than for nonrespiratory specimens, particularly body fluids.

• In low TB incidence settings, smear microscopy has lower specificity – a positive smear could be due to nontuberculous mycobacteria (NTM).

• Smear microscopy has lower sensitivity in childhood TB and extrapulmonary disease, especially in HIV-infected people.

• Smear microscopy cannot be used to determine drug resistance.” (PHAC, 2013)

Media Culture of M. Tuberculosis – “Mycobacterial culture, using both solid and liquid media, is considered the gold standard for diagnosis, and the use of broth-based culture methods for DST is the standard of practice in North America” (PHAC, 2013).

The benefits of culture:

  • identification
  • DST
  • further use of culture isolates for molecular epidemiology using DNA fingerprinting.
  • Culture can be performed on all specimen types.

The draw backs of culture:

  • results typically take 2-8 weeks, depending on the culture method used and the number of MTBC bacteria in the inoculum.

Nucleaic acid amplification test (NAAT)

The benefits of NAAT:

  • enables multi-drug resistant TB strain detection (unlike the other testing methods).
  • specificity of the commercial NAAT is very high in all specimens (90%-100%)
  • sensitivity of commercial NAATs to detect TB is high (>95%) in sputum smear-positive samples (PHAC, 2013)

The drawbacks of NAAT:

  • costly
  • inaccessible to the poorer regions and remote areas in the world
  • sensitivity is lower (50%-70%) when smear-negative/culture-positive specimens are tested.
  • sensitivity is also lower in extrapulmonary specimens.
  • a negative NAAT result should not be used to rule out TB, especially in paucibacillary forms of TB (i.e. smear-negative and extrapulmonary TB).
  • requires sophisticated laboratory infrastructure and highly skilled technicians
  • The risk of contaminating the test site with amplified DNA requires stringent quality control procedures and a specific infrastructure to limit contamination (PHAC, 2013)

2. What should be done for the patient and his roommates? Assuming he attended activities/procedures outside his room during his stay – would you follow the other patients?

This patient should be placed in a single room and placed on airborne infection isolation in a negative pressure room (Lautenbach, p. 335). If that is not possible place each patient on airborne and contact precautions seeing as the patient has been coughing  for 2 weeks in this shared space in close to his other roomates/patients. It is important to note that “If appropirate facilites for isolation of potentially infectious patients are not available on-site, an agreement should be in place to faciliate prompt transfer of such patients to alternate facilites” (Lautenbach, p354)

Yes I would follow and closely monitor all patients, visitors and staff who were in this patient’s proximity, tracing back contacts over the 2 weeks he was coughing. All contacts who were potentially exposed should undergo comprehensive tuberculin skin testing (Lautenbach, p. 335)

Lautenbach, p. 354, states that long term care facilities need to monitor for:

  • skin test conversions among residents and staff
  • identify and promptly evaulate patients with pulmonary symotoms or radiologic findings consistent with tuberculosis
  • immediately isolate patients with potential of proven pulminary tuberculosis
  • trace exposed patients and staff
  • initate prophylactic isoniazid therphy

3. What advice will you give to the staff in terms of their follow-up and protection? What are the Canadian recommendations regarding initial and routine screening of hospital staff for tuberculosis?

Follow-up and protection:

  • Staff should use N95 respirators when caring for the infected patient in his negative pressure room (Lautenbach, p335)
  • UV germicial irradiation of all potentially exposed contact surfaces should be undertaken to prevent infection spread via those surfaces (Lautenbach, p. 335)
  • Potentially exposed patients and staff should be tested for TB based on risk assessment and CDC guidelines (Lautenbach, p. 322).
  • Staff with underlying immunocompromising conditions should be discouraged from caring for the patient with TB.
  • Seeing as this patient’s family state he has not been known to be exposed to tuberculosis, nosocomial or cummunity acquired infection should be suspected and with that suspcision an immediate investigation should be undertaken and active, corrective steps should be implemented (Lautenbach, p. 325)
  • Consulation with public health official and experts in healthcare epidemiology and infection control should occur
  • based on the risk assessment, appropriate administrative, environmental and respiratory protection policies to prevent occupational exposure to and nosocomial transmission from the infectious or potentially infectious individual should put be in place (Lautenbach, p. 335).

Initial and routine screening:

“Prior to admission and employment all residents and employees of these facilities are to be assessed for their risk of tuberculosis.” (PICNET, p9).

  • Patients under 60 years – tuberculin skin test. Chest x-ray for those with a positive tuberculin reaction. (PICNET, p9)
  • Patients 60 years and over – chest x-ray only. Where there is difficulty obtaining a chest x-ray prior to or at the time of admission a normal chest x-ray completed within one year preceding admission for asymptomatic residents is acceptable (PICNET, p9).

For staff “The occupational medicine, hospital epidemiology and institutional biosafety programs should work together to establish effective ongoing tuberculosis prevention and management program” (Lautenbach, p. 320).

  • new employees should receive intradermal Mantoux skin testing unless they have the employee has prior documentation of active TB, previous positive skin test, and/or completion of therapy for infection (Lautenback, p. 320).
  • The whole blood interferon-y release assay could also be used, however discordant results have been reported between this and the skin test. (Lautenbach, p320)

4. What should be done for the patient and his roommates? Assuming he attended activities during the day, should you follow the rest of the patients on the ward?

note question 2 is very similiar therefore see it for answer.

5.Do you think this represents primary or reactivation tuberculosis? Justify your answer and explain what primary and reactivation tuberculosis means.

Considering that the family states this patient has not been knowingly exposed to TB we might consider sources for his infection. That said this patient is elderly, in long term care and would have few avenues of contracting a novel TB infection, with a weakened immune system dormant TB may reactive.

“All residents entering long term care facilities should have a baseline diagnosis test for LTBI performed… unless they are documented to have had a positive result previously” (Lautenbach, p. 338). We can hope we would have a TB test indicating the patient’s status upon admission.

If this patient’s infection represents a primary infection then potential sources he was exposed to need to be investiaged, such as staff, family members, visitors and patients.

Given age and accompanying immunocompromising factors along with the rigorous testing of all newly admitted patients and newly employed staff it is most probably that this patient has reactivation TB. However without knowing this patient’s TB immunity status prior to admission it is also possible the patient could have acquaried a primary infection from travelling family members or staff newly infected, other patients with re-activation (who also have been assumed to simply have a flu-like illness thus far). The results of the outbreak investigation and testing of patients and staff in the facility along with the patient’s TB test admission results would be needed to answer this question for certain.

From U.S. CDC Guidelines for the investigation of contacts of persons with infectious Tuberculosis the following data needs collecting in order to proceed with an thorough answer to this question:

“Multiple factors are relevant to a contact investigation, including the following: • history of previous exposure to TB,

• history of previous TB disease and treatment,

• anatomical sites of TB disease,

• symptoms of the illness,

• date of onset,

• chest radiograph results,

• other results of diagnostic imaging studies,

• diagnostic specimens that were sent for histologic or bac- teriologic analysis (with dates, specimen tracking num- bers, and destinations),

• current bacteriologic results,

• anti-TBchemotherapyregimen(withdates,medications, dosages, and treatment plan),

• results from HIV testing,

• the patient’s concurrent medical conditions (e.g., renal failure implies that a renal dialysis center might be part of the patient’s recent experience),

• other diagnoses (e.g., substance abuse, mental illness, or dementia) that impinge directly on the interview, and

• identifying demographic information (e.g., residence, employment, first language, given name and street names, aliases, date of birth, telephone numbers, other electronic links, and next-of-kin or emergency connections).” (MMWR, 2005)

Primary tuberculosis: the “first infection by Mycobacterium tuberculosis, typically seen in children but also occurs in adults, characterized in the lungs by the formation of a primary complex consisting of small peripheral pulmonary focus with spread to hilar or paratracheal lymph nodes; may proceed to cavitate or heal with scarring or may progress.” (Farlex, 2012).

Reactivation tuberculosis: is “a form of secondary tuberculosis that recurs as a result of the activation of a dormant endogenous infection. Causes of the reactivation may include loss of immunity, hormonal changes, or poor nutrition.” (Mosby’s, 2009).

6. What infection control measures would you have implemented if this had been non-tuberculous Mycobacterium?

Non-tuberculin mycobacterium are opportunistic organisms affecting immunocompromized and immunocompetent patients with a broad spectrum of virulence (Ryu, Koh and Daley, 2016). The most common Mycobacterial species causing infection are  Mycobacterium avium complex (MAC), M. abscessus complex (MABC) and M. kansasii (Ryu, Koh and Daley, 2016).

Due to variable virulence, airborne, droplet (airborne covers this) and contact precautions should be implemented until lab results return identifying strain. From there a treatment plan can be drawn up according to the specific strain. Note that though mode of infection is difficult to identify, infiection via  ingestion, inhalation or implantation (Johnson and Odell, 2014). Sources of infection such as probable inhalation of aerosoled droplets small enough to enter lung alveoli are the source of pulmonary NTM. Non-tubuculosis Mycobacterium exist in water and soil proving the patient’s general environment could also be a source of infection(Johnson and Odell, 2014).

However, identification of Mycobacterium organisms in pulminary specimen culture does not always indicate active infection (Johnson and Odell, 2014). That said it is difficult to treat and recurrences of infection due to the original organism is common (Johnson and Odell, 2014) and long courses of antibiotic treatment are necessary.

Mycobacterium are aerobic, non-motile bacterial that have lipid rich, hydrophobic cell walls much thicker than other bacterial strains (Johnson and Odell, 2014). The thick cell walls pose infection control obstacles as it enables the bacterium resistance to disinfectants, antibiotics and heavy metals (Johnson and Odell, 2014). Non-tubuculosis mycobacterium (NTM)  are associated with biofilms which promote it’s antibiotic and disintectant resistant properties. NTM are hydrophobic and readily aeorsolize from water, they are also quite resitant to high temperatures and low pH posing further sterilization and infection control challenges (Johnson and Odell, 2014).

Water systems such as those in general hospital, hemodialysis and dental centers have high rates of Mycobacterium colonization (Johnson and Odell, 2014) so methods of sterilizing water should be assessed by infection control if the facility’s water supply proves contaminated.
7. What is MDR? XDR? What are the treatment and Infection Control implications?

MDR stands for Multi-drug resistant.

XDR is extensively drug-resistant TB. “XDR TB is a rare type of multidrug-resistant tuberculosis (MDR TB) that is resistant to isoniazid and rifampin, plus any fluoroquinolone and at least one of three injectable second-line drugs (i.e., amikacin, kanamycin, or capreomycin). MDR TB is caused by an organism that is resistant to at least isoniazid and rifampin, the two most potent TB drugs.” (CDC, 2013).

Treatment and Infection Control implications:

  • XDR TB is resistant to the most treatment options
  • the limited, remaining treatment options are less effective (30-50%), have more side effects, and are more expensive.
  • HIV infected patients or those with other immunocompromizing conditions are at far greater risk of contracting TB and XDR TB
  • Co-infected TB and HIV patients have a far higher mortality rates than others once TB is contracted. (CDC, 2013)

XDR TB is on the rise globally and is more common in patients who:

  • Have HIV
  • Do not take their TB medicine regularly
  • Do not take all of their TB medicines as prescribed by their doctor
  • Develop  re-activation TB
  • Reside in or have immigrated from areas of the world where drug-resistant TB is common
  • Have spent time with someone known to have drug-resistant TB disease (CDC, 2013)

References:

1. Lautenbach, E., Woeltje, K., and Malani, P. 2010. Practical HealthcareEpidemiology, 3rd ed.

2. Johnson, M. M., & Odell, J. A. (2014). Nontuberculous mycobacterial pulmonary infections. Journal of Thoracic Disease, 6(3), 210–220. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3949190/

3. Public Health Agency of Canada. (2013). Canadian Tuberculosis Standards. 7th ed. Accessed April 16 from http://www.respiratoryguidelines.ca/tb-standards-2013

4. Ryu, Y. J., Koh, W.-J., & Daley, C. L. (2016). Diagnosis and Treatment of Nontuberculous Mycobacterial Lung Disease: Clinicians’ Perspectives. Tuberculosis and Respiratory Diseases, 79(2), 74–84. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4823187/

5. PICNET. (2011).  Residential Care Infection Prevention and Control Manual. Accessed April 17, 2017 from https://www.picnet.ca/wp-content/uploads/PICNet_Residential_Care_Manual_2011.pdf

6. Elsevier. (2009). Mosby’s Medical Dictionary, 9th edition.

7. Farlex. (2012). Farlex Partner Medical Dictionary.

8. Department of health and human services centers for disease control and prevention. (2005). Guidelines for the investigation of contacts of persons with infectious Tuberculosis. Accessed April 18, 2017 from https://www.cdc.gov/mmwr/pdf/rr/rr5415.pdf

9. CDC. (2013). Extensively Drug-Resistant Tuberculosis (XDR TB). Accessed April 18, 2017 from https://www.cdc.gov/tb/publications/factsheets/drtb/xdrtb.htm