HomeTable 2a. Tuberculosis (TB) exposures in healthcare or long-term care settings linked to absent or sub-optimal baseline TB screening in health care workers (HCWs)
| Research Question: Have absent or sub-optimal baseline TB screening in HCWs been linked to TB exposures in healthcare or long-term care facilities? This body of evidence informs Chapter 14 recommendations on HCW testing and treating for TB infection |
||||||
| Study | Setting | Trans- mission |
Study Design | Quality | Directness | Critical Appraisal ResultsA |
| Balmelli15 2014 | Acute | No | Weak | Medium | Direct | Study Number: Three epidemiological investigations provide limited evidence of a TB exposure from an infectious HCW in a health care setting, and link exposures to absent or sub-optimal baseline TB screening. Furthermore, Jonsson et al. reports that a contact investigation of exposed HCW was limited due to missing baseline tuberculin skin test data. Study Quality: The identified studies were assessed to be of low to medium quality by two appraisers. Consistency of Results: Three studies consistently identified missing or sub-optimal screening of HCWs upon hire as primary and attributed causes of exposure. This evidence is considered consistent. Directness: These studies report missing or sub-optimal baseline screening of HCW to have led to TB transmission from infectious HCWs to colleagues and other patients. The remaining study (Jonsson et al.) provides indirect evidence that baseline TB testing data is valuable to post-exposure contact investigations. Generalizability: Overall, this evidence is generalizable to Canadian hospital and long-term care settings. Strength of Body of Evidence: Weak to Moderate |
| Khalil11 2013 | LTC | Yes | Weak | Low | Direct | |
| Mor37 2018 | LTC | Yes | Weak | Low | Direct | |
| Jonsson24 2013 | Acute | Yes | Weak | Medium | Extrapolation | |
| Overall | Weak | Low – Medium | Direct | |||
ARating the quality of the overall body of available evidence for specific recommendations was conducted using the Public Health Agency of Canada Critical Appraisal Toolkit (CAT). Moralejo D, Ogunremi T, Dunn K. Critical Appraisal Toolkit (CAT) for assessing multiple types of evidence. Can Commun Dis Rep. 2017;43(9):176-81. https://doi.org/10.14745/ccdr.v43i09a02
Table 2b. Tuberculosis (TB) risk (latent or active TB infection) among health care workers (HCWs) compared to non-HCW populations in low-incidence countries
| Research Question: Is TB risk (latent or active TB infection) among HCWs in low-incidence counties higher when compared to the general population? This body of evidence informs Chapter 14 recommendations on HCW testing and treating for TB infection |
||||||
| Study | Country | HCW vs. non-HCW | Study Design | Quality | Directness | Critical Appraisal ResultsA |
| Diel77 2018 | Germany | Higher TB risk | Weak | Medium | Extrapolation | Study Number: Five studies report on TB risk among HCWs vs. non-HCW or general population groups. Three studies used population-based surveillance data, providing direct evidence that TB risk is similar between HCWs and non-HCWs, and any identified differences were not statistically significant. Two studies provide evidence that can be extrapolated to describe TB risk among HCWs. Youakim compared TB occupational compensation claims in British Columbia, Canada from 1999-2008, and found registered nurses to be at increased risk of TB infection claims, compared to other occupation groups. An analysis of TB clusters by Diel et al. found HCW were more likely to be associated with a case cluster linked to transmission at work, compared to non-HCWs. Study Quality: Included studies were assessed to be of medium quality Consistency and Directness of Results: The three studies providing direct evidence are consistent, concluding no evidence of elevated TB risk among HCWs, compared to non-HCWs. Two studies provide evidence that can be inferred to suggest that HCWs, such as nurses, are at increased risk for occupational TB exposures and transmissions. Generalizability: Overall, this evidence is generalizable to Canadian hospital and long-term care settings. Strength of Body of Evidence: Moderate Note: A systematic review by the World Health Organization found TB risk to be elevated among HCW compared to the general public in high and low burden countries. However, this review was not limited to recent evidence (inclusion criteria: studies published after 1946) |
| Davidson4 2017 | United Kingdom | Similar TB risk | Moderate | Medium | Direct | |
| Gehanno9 2017 | France | Similar TB risk | Weak | Low | Direct | |
| Lambert6 2012 | United States | Similar TB risk | Weak | Medium | Direct | |
| Youakim8 2016 | Canada | Higher TB risk | Weak | Medium | Extrapolation | |
| Overall | Similar TB risk | Weak | Medium | Direct | ||
ARating the quality of the overall body of available evidence for specific recommendations was conducted using the Public Health Agency of Canada Critical Appraisal Toolkit (CAT). Moralejo D, Ogunremi T, Dunn K. Critical Appraisal Toolkit (CAT) for assessing multiple types of evidence. Can Commun Dis Rep. 2017;43(9):176-81. https://doi.org/10.14745/ccdr.v43i09a02
Table 2c. Tuberculosis (TB) exposures linked to delayed diagnosis and initiation of airborne precautions in patients or residents
| Research Question: Have delayed diagnosis of TB and initiation of airborne precautions in patients or residents been linked to TB exposures in healthcare or long-term care facilities? This body of evidence informs Chapter 14 recommendations and good practice statements on identifying individuals with respiratory TB in the healthcare settings. |
||||||
| Study | Setting | Trans- mission |
Study Design | Quality | Directness | Critical Appraisal ResultsA |
| de Perio23 2014 | Acute | Yes | Weak | Medium | Extrapolation | Study Number: Ten observational studies, nine outbreak investigations and a single cross-sectional study, provide evidence to support delayed diagnosis and initiation of airborne precautions among active TB cases can lead to TB transmission in healthcare settings. In many of the reported investigations, at least one active TB infection among investigated contacts was linked to an index patient with a missed or delayed diagnosis by common epidemiology or infection strain. The cross-sectional study by Uppal et al., reports atypical presentation of TB infections and delays in TB diagnosis as the root causes of many TB exposures identified in a single healthcare facility. Study Quality: Across studies, quality was variable, from low to medium. Consistency of Results: The majority of studies were from acute care settings, but exposure events, contact investigations and findings were variable. All of the included studies identified delays in diagnosis and initiation of airborne precautions as infection prevention and control gaps linked to exposure event. Directness: These studies provide direct evidence to confirm TB transmission in healthcare settings due to gaps in infection prevention and control measures linked to exposure events, particularly delays in diagnosis and prompt initiation of airborne precautions. Generalizability: Overall, this evidence is generalizable to Canadian hospital and long-term care settings. Strength of Body of Evidence: Moderate |
| Grisaru-Soen14 2014 | Acute | Yes | Weak | Low | Direct | |
| Holden18 2018 | Acute | Yes | Weak | Low | Direct | |
| Jonsson24 2013 | Acute | Yes | Weak | Medium | Direct | |
| Kan40 2013 | Acute | Yes | N/A | N/A | Extrapolation | |
| Khatami34 2017 | Acute | No | Weak | Low | Direct | |
| Medrano12 2014 | Acute | Yes | Weak | Medium | Direct | |
| Townes41 2016 | Outpatient | No | Weak | Low | Direct | |
| Uppal20 2014 | Acute | No | Weak | Medium | Direct | |
| Harris22 2013 | LTC | Yes | Weak | Low | Direct | |
| Overall | Weak | Medium | Direct | |||
ARating the quality of the overall body of available evidence for specific recommendations was conducted using the Public Health Agency of Canada Critical Appraisal Toolkit (CAT). Moralejo D, Ogunremi T, Dunn K. Critical Appraisal Toolkit (CAT) for assessing multiple types of evidence. Can Commun Dis Rep. 2017;43(9):176-81. https://doi.org/10.14745/ccdr.v43i09a02
Table 2d. Tuberculosis (TB) exposures due to premature discontinuation of airborne precautions
| Research Question: Have premature discontinuation of airborne precautions in patients or residents been linked to TB exposures in healthcare or long-term care facilities? This body of evidence informs Chapter 14 recommendations on identifying individuals with respiratory TB in the healthcare setting |
||||||
| Study | Setting | Trans- mission |
Study Design | Quality | Directness | Critical Appraisal ResultsA |
| Holden18 2018 | Acute | Yes | Weak | Low | Extrapolation | Study Number: Three epidemiological investigations report premature discontinuation of airborne precautions linked to exposure. Study Quality: Study quality between the two studies reporting primary evidence was low to medium. Consistency of Results: Both studies report premature discontinuation of airborne precautions. In one instance, airborne precautions were discontinued before sputum analysis. In the other, airborne precautions were removed from a still-infectious patient who completed 14 days of effective therapy but remained symptomatic. Directness: One study provides direct evidence of missing smear negative sputum. The other study provides extrapolated evidence that suggests sputum smear positivity was not considered when airborne precautions were removed, as the only consideration for discontinuation was completion of treatment. Generalizability: Overall, this evidence is generalizable to Canadian hospital and long-term care settings. Strength of Body of Evidence: Weak |
| Jonsson24 2013 | Acute | Yes | Weak | Medium | Direct | |
| Kan40 2013 | Acute | Yes | N/A | N/A | Extrapolation | |
| Overall | Weak | Low | Extrapolation | |||
ARating the quality of the overall body of available evidence for specific recommendations was conducted using the Public Health Agency of Canada Critical Appraisal Toolkit (CAT). Moralejo D, Ogunremi T, Dunn K. Critical Appraisal Toolkit (CAT) for assessing multiple types of evidence. Can Commun Dis Rep. 2017;43(9):176-81. https://doi.org/10.14745/ccdr.v43i09a02
Switch To: Français