Can workplaces be predictors for recent onset latent tuberculosis in health care workers?

Risk Factors for Latent Tuberculosis among Health-care Workers in Sri Lanka

INTRODUCTION

Management of latent tuberculosis infection (LTBI) was introduced as a national policy in Sri Lanka in 2022, targeting high-risk groups, including health-care workers (HCWs). This study aimed to identify the potential risk factors for LTBI among HCWs in government hospitals.

METHODS

A case-control study was conducted. Cases and controls were identified by a screening survey conducted among those tested by the tuberculin skin test (TST). The survey was conducted among HCWs of eight government hospitals in Colombo in 2022. LTBI cases were defined as TST positives (≥10 mm) without a history of pulmonary tuberculosis (TB) and controls were those rated as negative. The cases-to-control ratio was 1:1, with a sample size of 128 cases and 128 controls. Multiple logistic regression analysis was conducted to identify the risk factors.

RESULTS

The significant risk factors identified included age ≥40 years (adjusted odds ratio [AOR] - 2.4, 95% confidence interval [CI]: 1.28-4.47) having a service duration of ≥6 years (AOR - 2.92, CI: 1.469-5.82), not maintaining distance (AOR - 2.83, CI: 1.43-5.58) and not wearing face masks when dealing with suspected or diagnosed TB patients (AOR - 3.55, CI: 1.80-7.00), and settings with inadequate TB infection control practices (AOR - 3.47, CI: 1.85-6.47).

CONCLUSION

Improving infection control measures, training HCWs on TB prevention, providing adequate personal protective equipment, and initiating screening for LTBI among HCWs are recommended.

Prevalence of latent tuberculosis infection among health workers in Afghanistan: A cross-sectional study

BACKGROUND

About 26% of the world's population may have latent tuberculosis infection (LTBI). Health care workers are a high-risk category because of their professional exposure.

METHODS

This cross-sectional study assessed the LTBI burden among health care workers in Afghanistan, a high-TB-burden country. We selected health facilities using a systematic sampling technique and invited all workers at the targeted health facilities to participate. Participants were interviewed about sociodemographic and exposure variables and received tuberculin skin tests for LTBI.

RESULTS

Of the 4,648 health care workers invited to participate, 3,686 had tuberculin skin tests. The prevalence of LTBI was found to be 47.2% (1,738 workers). Multivariate analysis showed that a body mass index of ≥ 30 and marriage were associated with an increased risk of LTBI. Underweight (body mass index of ≤ 18 and below) and normal body mass index had no association with increased risk of LTBI.

CONCLUSION

LTBI is high among health care workers in Afghanistan. We recommend instituting infection control measures in health facilities and screening workers for timely TB diagnosis.

Factors Associated with Latent Tuberculosis Infection among the Hospital Employees in a Tertiary Hospital of Northeastern Thailand

Latent tuberculosis infection (LTBI) can develop into tuberculosis (TB). The WHO requires the discovery and management of LTBI among high-risk groups. Health care workers (HCWs) constitute a high-risk group. Factors associated with LTBI among HCWs in Thailand need further study. The current study aimed to explore the factors related to LTBI among Thai HCWs. A hospital-based, matched case-control study was conducted. All cases and controls were HCWs at a tertiary hospital in northeastern Thailand. Between 2017 and 2019, a total of 85 cases of interferon-γ release assays (IGRAs)-proven LTBI, and 170 control subjects were selected from a hospital (two controls per case). The two recruited controls were individually matched with LTBI cases by sex and age (±5 years). Secondary data were obtained from the occupational health and safety office. Case HCWs had a higher proportion of significant factors than control HCWs (i.e., working closely with pulmonary TB-94.1% vs. 88.8%, and working in the area of aerosol-generating procedures (AGPs) 81.2% vs. 69.4%). The bivariate conditional logistic regression showed that the occurrence of LTBI in HCWs was statistically significant (p-value < 0.05), particularly with respect to: workplaces of AGPs (crude OR = 1.90, 95% CI: 1.01-3.58, p = 0.041); among HCWs performing AGPs (crude OR = 2.04, 95% CI: 1.20, 3.48, p = 0.007); and, absent Bacille Calmette-Guérin (BCG) scar (crude OR = 2.59, 95% CI: 1.50-4.47, p = 0.001). Based on the multivariable conditional logistics analysis, HCWs who performed AGPs while contacting TB cases had a statistically significant association with LTBI (adjusted OR = 1.82, 95% CI: 1.04-3.20, p = 0.035). HCWs who reported the absence of a BCG scar had a statistically significant association with LTBI (adjusted OR = 2.49, 95% CI: 1.65-5.36, p = 0.001), whereas other factors including close contact with TB (adjusted OR = 2.44, 95% CI: 0.74, 8.09, p = 0.123) were not significantly associated with LTBI. In conclusion, HCWs who performed AGPs and were absent a BCG scar had a significant association with LTBI, while other factors played a less critical role.

Prevalence and Risk Factors for Latent Tuberculosis Infection among Health Care Workers in China: A Cross-Sectional Study

Background

Health care workers (HCWs) are at risk of latent tuberculosis infection (LTBI). In China, tuberculosis (TB) is a major public health problem, but the prevalence of LTBI in HCWs especially in the hospital for pulmonary diseases has not been assessed enough. The aim of this study was to determine the prevalence and putative risk factors of LTBI among HCWs in a chest hospital and a TB research institute in China.

Methodology/Principal Findings

A cross-sectional study was conducted among HCWs in China in 2012. LTBI was assessed by T-SPOT.TB, and information on HCWs was collected using a standardised questionnaire. Risk factors for LTBI were analyzed by univariate and multivariate regression. The overall prevalence of LTBI among HCWs was 33.6%. Analyzed by job category, the highest prevalence was found among laboratory staff (43.4%). In the different workplaces, the proportion of LTBI was significantly higher among the high risk workplaces (37.4%) compared to the low risk workplaces. The duration of employment had a significant impact on the prevalence of LTBI. Positive T-SPOT.TB test results accounted for 17.6%, 16.8%, 23.5%, 41.8% and 41.6% in groups of ≤2, 3–5, 6–10, 11–20, and >20 working years respectively. In multivariate analysis, job categories (Laboratory staff [2.76 (95% CI: 1.36; 5.60)], technician staff [2.02 (95% CI: 1.12; 3.64)]); working duration as a HCW for 11 to 20 years [3.57 (95% CI: 1.46; 8.71)], and 20 years above [3.41 (95% CI: 1.28; 9.11)]; and the history of household TB contact [2.47 (95% CI: 1.15; 5.33)] were associated with increased risk of LTBI.

Conclusions/Significance

Prevalence of LTBI estimated by T-SPOT.TB is high among Chinese HCWs and working duration, job category and the history of household TB contact were associated with increased risk. These data highlight adequate infection control measures should be undertaken.

Latent tuberculosis in nursing professionals of a Brazilian hospital

Tuberculosis (TB) is considered an occupational disease among health-care workers (HCWs). Direct contact with TB patients leads to an increased risk to become latently infected by Mycobacterium tuberculosis. The objective of this study is to estimate the prevalence of latent M. tuberculosis minfection among nursing professionals of a hospital in Rio Grande do Sul, Brazil, assessed by tuberculin skin test (TST). From November 2009 to May 2010, latent M. tuberculosis infection was assessed by TST in 55 nursing professionals. Epidemiological information was collected using a standardized questionnaire. A positive TST result (> or = 10 mm) was observed in 47.3% of the HCWs tested. There was no significant difference in TST positivity when duration of employment or professional category (technician or nurse) was evaluated. The results of this work reinforce the need for control measures to prevent latent M. tuberculosis infection among nursing professionals at the hospital where the study was conducted.

Risk of latent TB infection in individuals employed in the healthcare sector in Germany: a multicentre prevalence study

BACKGROUND

Healthcare workers are still recognised as a high-risk group for latent TB infection (LTBI). Therefore, the screening of people employed in the healthcare sector for active and LTBI is fundamental to infection control programmes in German hospitals. It was the aim of the study to determine the prevalence and putative risk factors of LTBI.

METHODS

We tested 2028 employees in the healthcare sector with the QuantiFERON-Gold In-tube (QFT-IT) test between December 2005 and May 2009, either in the course of contact tracing or in serial testing of TB high-risk groups following German OSH legislation.

RESULTS

A positive IGRA was found in 9.9% of the healthcare workers (HCWs). Nurses and physicians showed similar prevalence rates (9.7% to 9.6%). Analysed by occupational group, the highest prevalence was found in administration staff and ancillary nursing staff (17.4% and 16.7%). None of the individuals in the trainee group showed a positive IGRA result. In the different workplaces the observed prevalence was 14.7% in administration, 12.0% in geriatric care, 14.2% in technicians (radiology, laboratory and pathology), 6.5% in admission ward staff and 8.3% in the staff of pulmonary/infectious disease wards. Putative risk factors for LTBI were age (>55 years: OR14.7, 95% CI 5.1-42.1), being foreign-born (OR 1.99, 95% CI 1.4-2.8), TB in the individual's own history (OR 4.96, 95% CI 1.99-12.3) and previous positive TST results (OR 3.5, 95% CI 2.4-4.98). We observed no statistically significant association with gender, BCG vaccination, workplace or profession.

CONCLUSION

The prevalence of LTBI in low-incidence countries depends on age. We found no positive IGRA results among trainees in the healthcare sector. Incidence studies are needed to assess the infection risk. Pre-employment screening might be helpful in this endeavour.