Prevalence and risk factors for latent tuberculosis infection among healthcare workers in Morocco

Prevalence of Latent Tuberculosis Infection Among Nurses Working in Critical Areas at a Tertiary Care Hospital in Riyadh, Saudi Arabia

Introduction Tuberculosis is a critical health issue worldwide. Most infected persons are asymptomatic and categorized as having a latent tuberculosis infection (LTBI). Healthcare workers (HCWs) are more prone to being infected with tuberculosis and should be enrolled in a screening program for early detection. Objectives The study aims to estimate the prevalence of LTBI among nurses working in critical areas which include adult intensive care units, pediatric intensive care units, emergency departments, oncology departments, dialysis departments, tuberculosis labs, isolation rooms, and cardiac center intensive care units. Methods A record-based cross-sectional survey measured the prevalence of LTBI among nurses working in critical areas at Prince Sultan Military Medical City (PSMMC), Riyadh, Saudi Arabia. We reviewed the occupational health records of all nurses working in critical areas from June 1, 2021, to June 1, 2022. We recorded the data reviewed throughout the year in the Occupational Health Department at PSMMC. We excluded all participants with previously documented positive tuberculin skin test (TST) from the study. We analyzed the sociodemographic data, working years, working location, job title, and TST results. Results We included a total of 771 out of 2025 nurses in this study. Participants were mostly women (88%) and in the 26-35-year age group (67.7%). Most of the participants were originally from the Philippines (66.3%). The overall LTBI prevalence among nurses was 34.5%. The highest prevalence of LTBI was among nurses working in the cardiac intensive care unit (53.5%), and the lowest prevalence was among nurses working in the isolation department (8.9%; p-value <0.0001). Those who worked more in the hospital were significantly more infected with LTBI (p-value <0.04). Conclusion LTBI remains a significant health risk worldwide and in the Middle East as well as among HCWs. This underscores the necessity of comprehensive pre-hiring screening, annual screening, infection control protocols, and active management of HCWs with LTBI.

Changes in the rate of bacillus tuberculosis infection in health workers in the first year of the COVID-19 epidemic in Kashan- Iran

Objective

This cohort study aimed to determine the prevalence and risk factors of latent tuberculosis infection among healthcare workers during the COVID-19 pandemic.

Methods

A one-year cohort study was conducted in a referral hospital in Kashan, involving 176 medical, educational, and cleaning personnel. Initial evaluations and tuberculin skin tests were performed, followed by a one-year follow-up period. Data were analyzed using SPSS version 26 software.

Results

Among the participants, 26.1% (46 individuals) tested positive for latent tuberculosis infection. Age was a significant risk factor, with a 3.6% increase in latent tuberculosis infection risk with each advancing year. Men had 2.19 times (1.10-4.35) the chance of having a latent infection compared to women. Hospital staff were 3.7 times more at risk of tuberculosis infection than students. Among the hospital job categories, nursing assistants had the highest chance of tuberculosis infection, 6.77 times higher than medical students, followed by cleaning staff and nurses. The ICU, General, and Obstetrics and Gynecology departments had an infection chance of 2.46 (1.11-5.46) compared to other departments. No new positive cases were detected during the follow-up period.

Conclusion

This study contributes to the understanding of latent tuberculosis infection prevalence and its risk factors among healthcare workers during the COVID-19 pandemic. The findings highlight the importance of infection control measures and targeted interventions to protect healthcare workers from occupational tuberculosis exposure.

Identification of new cases of tuberculosis during the COVID-19 pandemic using model strategic management

Introduction: Tuberculosis (TB) is a world health problem that causes the third-largest death after cardiovascular and respiratory diseases. One of the causes of transmission of environmental factors is controlling the mobilization of individuals suffering from tuberculosis. This research aims to develop a strategic model of finding new TB cases based on region. Method: This descriptive research utilizes primary and secondary data. Variables consist of geographical and demographic characteristics, resources, tuberculosis prevalence, and indicators of tuberculosis response processes. The TB management planning model document is based on the experiences of health centers Perak Timur, Wonokromo, and Siwalankerto in maximizing TB case detection. Results: The management model outlines policies and procedures based on the variables. For example, the detection of new TB patients became a priority at the health center in Perak Timur. In contrast, the health center in Wonokromo focused on developing cadres and private practice physicians. Conclusions: This research provides an overview of the aspects that need attention and improvement by discovering different new cases in each region.  

Sex and Gender Differences in Tuberculosis Pathogenesis and Treatment Outcomes

Tuberculosis remains a daunting public health concern in many countries of the world. A consistent observation in the global epidemiology of tuberculosis is an excess of cases of active pulmonary tuberculosis among males compared with females. Data from both humans and animals also suggest that males are more susceptible than females to develop active pulmonary disease. Similarly, male sex has been associated with poor treatment outcomes. Despite this growing body of evidence, little is known about the mechanisms driving sex bias in tuberculosis disease. Two dominant hypotheses have been proposed to explain the predominance of active pulmonary tuberculosis among males. The first is based on the contribution of biological factors, such as sex hormones and genetic factors, on host immunity during tuberculosis. The second is focused on non-biological factors such as smoking, professional exposure, and health-seeking behaviors, known to be influenced by gender. In this chapter, we review the literature regarding these two prevailing hypotheses by presenting human but also experimental animal studies. In addition, we presented studies aiming at examining the impact of sex and gender on other clinical forms of tuberculosis such as latent tuberculosis infection and extrapulmonary tuberculosis, which both appear to have their own specificities in relation to sex. We also highlighted potential intersections between sex and gender in the context of tuberculosis and shared future directions that could guide in elucidating mechanisms of sex-based differences in tuberculosis pathogenesis and treatment outcomes.

Determinants of QuantiFERON Plus-diagnosed tuberculosis infection in adult Ugandan TB contacts: A cross-sectional study

BACKGROUND

The tuberculin skin test is commonly used to diagnose latent tuberculosis infection (LTBI) in resource-limited settings, but its specificity is limited by factors including cross-reactivity with BCG vaccine and environmental mycobacteria. Interferon-gamma release assays (IGRA) overcome this problem by detecting M. tuberculosis complex-specific responses, but studies to determine risk factors for IGRA-positivity in high TB burden settings are lacking.

METHODS

We conducted a cross-sectional study to determine factors associated with a positive IGRA by employing the QuantiFERON-TB® Gold-plus (QFT Plus) assay in a cohort of asymptomatic adult TB contacts in Kampala, Uganda. Multivariate logistic regression analysis with forward stepwise logit function was employed to identify independent correlates of QFT Plus-positivity.

RESULTS

Of the 202 participants enrolled, 129/202 (64%) were female, 173/202 (86%) had a BCG scar, and 67/202 (33%) were HIV-infected. Overall, 105/192 (54%, 95% CI 0.48-0.62) participants had a positive QFT Plus result. Increased risk of QFT-Plus positivity was independently associated with casual employment/unemployment vs. non-casual employment (adjusted odds ratio (aOR) 2.18, 95% CI 1.01-4.72), a family vs. non-family relation to the index patient (aOR 2.87, 95% CI 1.33-6.18), living in the same vs. a different house as the index (aOR 3.05, 95% CI 1.28-7.29), a higher body mass index (BMI) (aOR per additional kg/m2 1.09, 95% CI 1.00-1.18) and tobacco smoking vs. not (aOR 2.94, 95% CI 1.00-8.60). HIV infection was not associated with QFT-Plus positivity (aOR 0.91, 95% CI 0.42-1.96).

CONCLUSION

Interferon Gamma Release Assay positivity in this study population was lower than previously estimated. Tobacco smoking and BMI were determinants of IGRA positivity that were previously unappreciated.

Prevalence of Tuberculosis Infection among Adults of Thiruvananthapuram District of Kerala as Measured by Interferon Gamma Release Assay - A Cross-Sectional Study

Background

To achieve the goals of the end tuberculosis (TB) strategy, strategies for management of TB infection (TBI) have to be expanded. The first step to devise policies is to understand the distribution and determinants of TBI in the community. The objectives of the study were to estimate the prevalence of TBI using Interferon Gamma Release Assay (IGRA) and its determinants among the adult population of Thiruvananthapuram district, Kerala.

Materials and Methods

A community-based, cross-sectional study using the stratified cluster sampling was carried out among the adults. TBI was detected using IGRA conducted on whole blood sample. Data on determinants were collected using a structured questionnaire by the face-to-face interview. The prevalence of TBI was estimated. Univariate and multivariate analysis was conducted to identify the determinants.

Results

Age standardized prevalence of TBI among 396 adults was 20.5% (95% confidence interval [CI] 16.52-24.48). On adjusting for the possible confounders, increasing age (adjusted odds ratio [OR] 1.028; 95% CI 1.008-1.048; P = 0.005), history of contact with active TB disease (adjusted OR 7.61; 95% CI 4.43-13.05; P < 0.001), childhood contact (adjusted OR 8.20; 95% CI 3.14-21.41; P < 0.001), and household contact (adjusted OR 10.12; 95% CI 5.39-18.98; P < 0.001) were found to be the determinants of TBI in this population.

Conclusion

The present study observed that nearly one-fifth of the adult population in the Thiruvananthapuram district has TBI. For the programmatic management, factors such as increasing age and contact history may be considered for the elimination of TBI in the state.

Possible sex difference in latent tuberculosis infection risk among close tuberculosis contacts

OBJECTIVES

More men than women develop and die of tuberculosis (TB). Fewer data exist on sex differences in latent TB infection (LTBI). We assessed for potential sex differences in LTBI acquisition among close TB contacts.

METHODS

Regional Prospective Observational Research for TB-Brazil is an observational multi-center cohort of individuals with culture-confirmed pulmonary TB and their close contacts. Participants were enrolled from five sites in Brazil from June 2015 - June 2019. Close contacts were followed for 24 months after enrollment, with LTBI defined as a positive interferon-γ release assay (IGRA; QuantiFERON 3rd or 4th generation) at baseline or 6 months. We performed univariate, bivariate, and multivariable logistic regression and propensity-score weighted models to assess odds ratios (OR) and 95% confidence intervals (CI) for LTBI acquisition by birth sex among close contacts.

RESULTS

Of 1093, 504 (46%) female close contacts were IGRA positive compared to 295 of 745 (40%) men. The unadjusted OR for IGRA positivity among women vs men was 1.31 (95% CI: 1.08-1.58). Bivariate adjustments yielded ORs in women vs men ranging from 1.19 to 1.33 (P-value range: <0.01-0.07). Multivariable regression and weighted models yielded similar ORs in women vs men, of 1.14 (95% CI: 0.92-1.41) and 1.15 (95% CI: 0.94-1.40), respectively.

CONCLUSION

The point estimate for LTBI among close TB contacts in Brazil was higher in women, though less pronounced in multivariable models. If the sex difference in LTBI is confirmed in additional settings, studies of possible underlying differences in socio-behavioral factors or TB pathogenesis are warranted.

Magnitude and associated factors of latent tuberculosis infection due to Mycobacterium tuberculosis complex among high-risk groups in urban Bobo-Dioulasso, Burkina Faso

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The overall prevalence of latent tuberculosis infection (LTBI) in this study was 63.36%.

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The positivity rate for the tuberculin skin test was higher compared with the QuantiFERON-TB Gold Plus test.

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The prevalence of LTBI was high among slaughterhouse workers (100%).

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Protozoal infection was found to be significantly associated with LTBI.

Objectives

Methods

Results

Conclusion

A tuberculin skin test survey among healthcare workers in two public tertiary care hospitals in Bangladesh

In Bangladesh, there is currently no data on the burden of latent TB infection (LTBI) amongst hospital healthcare workers (HCWs). This study aimed to determine the prevalence of LTBI and compare the prevalence among HCWs in two public tertiary care hospitals. Between September 2018 and August 2019, we conducted a cross-sectional study in two public tertiary care general hospitals. Using a survey and tuberculin skin test (TST), we assessed risk factors for LTBI, adjusting for known and plausible confounders. In addition, a facility assessment was undertaken to understand the implementation of relevant IPC measures. The prevalence of LTBI among HCWs was 42%. HCWs spent a median of 6 hours (SD = 1.76, IQR 2.00) per day and attended an average of 1.87 pulmonary TB patients per week. HCWs did not receive any TB IPC training, the wards lacked a symptom checklist to screen patients for TB, and no masks were available for coughing patients. Seventy-seven percent reportedly did not use any facial protection (masks or respirators) while caring for patients. In the multivariable model adjusting for hospital level clustering effect, TST positivity was significantly higher among HCWs aged 35-45 years (aOR1.36, 95% CI: 1.06-1.73) and with >3 years of service (aOR 1.67, 95% CI: 1.62-1.72). HCWs working in the medicine ward had 3.65 (95% CI: 2.20-6.05) times, and HCWs in the gynecology and obstetrics ward had 2.46 (95% CI: 1.42-4.27) times higher odds of TST positivity compared to HCWs working in administrative areas. This study identified high prevalence of LTBI among HCWs. This may be due to the level of exposure to pulmonary TB patients, and/or limited use of personal protective equipment along with poor implementation of TB IPC in the hospitals. Considering the high prevalence of LTBI, we recommend the national TB program consider providing preventative therapy to the HCWs as the high-risk group, and implement TB IPC in the hospitals.

RISK FACTORS OF LATENT TUBERCULOSIS INFECTION IN HEALTHCARE WORKERS AT HOSPITALS IN JEMBER CITY INDONESIA

Background:

Healthcare workers in Tuberculosis (TB) and non-TB units in hospitals have a high risk of experiencing Latent Tuberculosis Infection (LTBI), because of exposure to droplets containing Mycobacterium tuberculosis. This study aims to prove LTBI incidence and risk factors to healthcare workers at the hospital in Jember City.

Material and Methods:

a cross-sectional study, from January to March 2020 in two hospitals in Jember City. Healthcare workers in the TB care and non-TB care unit were examined using Tuberculin skin test (TST) with a cut off ≥ 10 mm for positive LTBI. Chest x-ray and clinical examination to rule out active TB and a standardized questionnaire were also used.

Results:

128 healthcare workers completed the questionnaires, clinical, tuberculin skin test (TST), and chest x-ray data. LTBI incidence of positive results 61.7% (n = 79). Contacts TB in the workplace (p value = 0.219; OR = 1.643; CI = 0.742-3.641) and a unit of work (p value = 0.102; OR = 0.760; CI = 0.559-1.031) has no relationship with LTBI. The profession (p value = 0.020; OR = 1.112; CI = 0.896-1.403), the duration of the work (p value = 0.039; OR = 2.984; CI = 1.067-8.342), and BCG immunization (p value =0.000; OR = 0.151; CI = 0.052-0.438) have important relationships with LTBI.

Conclusion:

TB infection with a high incidence, a risk of transmission to healthcare workers, and a relationship between occupational risk factors and LTBI among healthcare workers in Jember City, Indonesia have been established in this study.

Association between indoor air pollution, tobacco smoke and tuberculosis: an updated systematic review and meta-analysis

OBJECTIVE

This study aims to further quantify evidence of the association between exposure to indoor air pollution (IAP), tobacco smoke etc., on the one hand and the risk of contracting tuberculosis (TB) on the other.

STUDY DESIGN

This was a systematic review and meta-analysis of articles published between June 2014 and February 2020 in PubMed, Web of Science, among others.

METHODS

We only included studies that controlled for confounders, screened both the exposed and unexposed study participants, and passive smoking studies that limited the study population to non-smokers. Quality of studies was assessed using the Newcastle-Ottawa scale. The analysis was conducted using STATA, and pooled effect sizes were calculated using the random-effects model, and heterogeneity was tested for using the Cochran Q test and I2 statistic.

RESULTS

A total of 26 articles were included in the final analysis. There was an increased risk of contracting TB among people exposed to IAP (risk ratio [RR] = 1.68, 95% confidence interval [CI] 1.108-2.542). We also observed a two-fold increase in the risk of contracting TB from exposure to secondhand tobacco smoke (RR = 2.15, 95%CI 1.419-3.242). Tobacco smoking doubled the risk of contracting TB (RR = 2.67, 95%CI 2.017-3.527). Furthermore, studies that used microbiological tests showed a higher RR compared to those that used other TB diagnostic methods.

CONCLUSION

Exposure to IAP and secondhand tobacco smoke increases the risk of contracting TB. Various disease prevention campaigns should include IAP awareness and encourage a shift to cleaner sources of energy.

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.

Tuberculosis Infection Screening in 5468 Italian Healthcare Students: Investigation of a Borderline Zone Value for the QFT-Test

Healthcare workers are at an increased risk of contracting Mycobacterium tuberculosis infection. Tuberculin skin test (TST) and interferon gamma release assay (IGRA) represent the available tests most used for the diagnosis of latent tuberculosis infection (LTBI). Different borderline zones have been proposed for defining conversions and reversions to improve the interpretation of the IGRA test results as part of serial testing. From 2012 to 2017, 5468 health students of an Italian University Hospital were screened for tuberculosis infection through the execution of the TST and, in case of positivity, of the QuantiFERON-TB® Gold In-Tube assay (QFT-GIT). The QFT-GIT is considered "borderline" with values from 0.35 to 0.99 IU/mL. Among the students who performed the QFT-GIT assay, 27 subjects presented a range of values defined as borderline. The QFT-GIT was repeated after 90 days on 19 subjects with borderline values and showed a negativization of the values in 14 students and a positive conversion in three cases, while for two students, a borderline value was also found for the second test, with a 74% regression of the borderline cases. The introduction of QuantiFERON borderline values is a useful assessment tool to bring out LTBI case candidates for chemoprophylaxis.

The Prevalence and Demographic Risk Factors for Latent Tuberculosis Infection (LTBI) Among Healthcare Workers in Semarang, Indonesia

Purpose

To determine the prevalence and demographic risk factors for latent tuberculosis infection (LTBI) among healthcare workers in Semarang, Indonesia.

Methods

A cross-sectional study involving 195 healthcare workers from 34 primary health centers was conducted from August to October 2019. The relationship between independent variables and dependent variables was analyzed using a multivariable logistic regression analysis.

Results

The prevalence of LTBI among healthcare workers in this study was 23.6%. Comorbidities were the only risk factor for LTBI identified among other risk factors (OR=3.39, 95% CI: 0.99–11.62, p=0.04). Other demographic factors such as age (OR=0.93, 95% CI: 0.45–1.92, p=0.839), gender (OR=0.79, 95% CI: 0.23–2.72, p=0.708, smoking habits (OR=2.54, 95% CI: 0.52–12.38, p=0.247), and length of work (OR=1.43, 95% CI: 0.70–2.91, p=0.331) were not significant risk factors for LTBI.

Conclusion

Healthcare workers suffering from comorbidity have a high risk for tuberculosis infection, and should not work in areas where they would be exposed to patients with tuberculosis. Healthcare workers need to apply occupational safety standards during contact with TB patients or specimens to minimize the disease transmission.