Administrative measures for preventing Mycobacterium tuberculosis infection among healthcare workers in a teaching hospital in Rio de Janeiro, Brazil

Intervenções em saúde do trabalhador - contexto, desafios e possibilidades de desenvolvimento: uma revisão de escopo

Resumo Objetivo: analisar a estrutura, o funcionamento das intervenções para prevenção de agravos e a promoção da saúde do trabalhador no Brasil, segundo os critérios de sistematicidade, agência transformativa e transformação. Métodos: foi realizada uma revisão de escopo de estudos empíricos publicados entre 2010 e 2019. Para avaliar e interpretar os achados e discutir suas possibilidades e tendências de desenvolvimento, utilizaram-se os três critérios mencionados. Resultados: foram incluídos 147 estudos; observou-se que o objeto da intervenção é mais comum em elementos isolados do sistema de atividade produtiva do que sobre o conjunto completo; a agência transformativa dos atores envolvidos é pouco estimulada; a transformação efetiva das condições que deram origem às intervenções aparece com mais frequência nas situações em que se pretendia mudar apenas aspectos proximais aos agravos de saúde. Conclusão: embora parte dos estudos reporte mudanças implementadas, a maioria deles não refere intervenções sobre os determinantes de saúde e não envolve os trabalhadores como protagonistas das mudanças. Os achados permitiram discutir possibilidades de desenvolvimento e desafios para intervenções.

Examining pulmonary TB patient management and healthcare workers exposures in two public tertiary care hospitals, Bangladesh

Implementation of tuberculosis (TB) infection prevention and control (IPC) guidelines in public tertiary care general hospitals remain challenging due to limited evidence of pulmonary TB (PTB) patients' duration of hospital stay and management. To fill this evidence gap, this study examined adult PTB patient management, healthcare workers' (HCWs) exposures and IPC practices in two public tertiary care hospitals in Bangladesh.Between December 2017 and September 2019, a multidisciplinary team conducted structured observations, a hospital record review, and in-depth interviews with hospital staff from four adult medicine wards.Over 20 months, we identified 1,200 presumptive TB patients through the hospital record review, of whom 263 were confirmed PTB patients who stayed in the hospital, a median of 4.7 days without TB treatment and possibly contaminated the inpatients wards. Over 141 observation hours, we found a median of 3.35 occupants present per 10 m2 of floor space and recorded a total of 17,085 coughs and 316 sneezes: a median of 3.9 coughs or sneezes per 10 m2 per hour per ward. Only 8.4% of coughs and 21% of sneezes were covered by cloths, paper, tissues, or by hand. The HCWs reportedly could not isolate the TB patients due to limited resources and space and could not provide them with a mask. Further, patients and HCWs did not wear any respirators.The study identified that most TB patients stayed in the hospitals untreated for some duration of time. These PTB patients frequently coughed and sneezed without any facial protection that potentially contaminated the ward environment and put everyone, including the HCWs, at risk of TB infection. Interventions that target TB patients screening on admission, isolation of presumptive TB patients, respiratory hygiene, and HCWs' use of personal protective equipment need to be enhanced and evaluated for acceptability, practicality and scale-up.

Evidence for the Use of Triage, Respiratory Isolation, and Effective Treatment to Reduce the Transmission of Mycobacterium Tuberculosis in Healthcare Settings: A Systematic Review

Evidence is limited for infection prevention and control (IPC) measures reducing Mycobacterium tuberculosis (MTB) transmission in health facilities. This systematic review, 1 of 7 commissioned by the World Health Organization to inform the 2019 update of global tuberculosis (TB) IPC guidelines, asked: do triage and/or isolation and/or effective treatment of TB disease reduce MTB transmission in healthcare settings? Of 25 included articles, 19 reported latent TB infection (LTBI) incidence in healthcare workers (HCWs; absolute risk reductions 1%-21%); 5 reported TB disease incidence in HCWs (no/slight [high TB burden] or moderate [low burden] reduction) and 2 in human immunodeficiency virus-positive in-patients (6%-29% reduction). In total, 23/25 studies implemented multiple IPC measures; effects of individual measures could not be disaggregated. Packages of IPC measures appeared to reduce MTB transmission, but evidence for effectiveness of triage, isolation, or effective treatment, alone or in combination, was indirect and low quality. Harmonizing study designs and reporting frameworks will permit formal data syntheses and facilitate policy making.

The Effectiveness of Individual and Environmental Infection Control Measures in Reducing the Transmission of Mycobacterium tuberculosis: A Systematic Review

Background

Transmission of Mycobacterium tuberculosis in healthcare settings is a preventable driver of the global tuberculosis epidemic. We aimed to assess the evidence for infection control interventions, including cough etiquette, engineering and personal respiratory protection measures, to prevent transmission of M. tuberculosis in healthcare settings.

Methods

Three independent systematic reviews were performed using 6 databases and clinical trials websites. Randomized trials, cohort studies, before-after studies, and case-control studies were included. Searches were performed for controlled studies evaluating respiratory hygiene, engineering, and personal respiratory protection measures. Outcome measures included the incidence of tuberculosis infection and disease. Studies involving transmission to either humans or animals were included.

Results

Evaluation of respiratory hygiene and cough etiquette interventions identified 4 human studies, with 22 855 participants, and 1 guinea pig study. Studies in humans evaluated the effects of multiple concurrent interventions. Patient use of surgical masks reduced infection by 14.8%, and tuberculosis disease was reduced by between 0.5% and 28.9%. Engineering and environmental interventions were evaluated in 10 studies of humans, including 31 776 human participants, and 2 guinea pig studies. Mechanical ventilation was associated with between 2.9% and 14% less infection. Nine studies of personal respiratory protection were included, including 33 913 participants. Infection was reduced by between 0% and 14.8% in studies where particulate respirators were used. The quality of included studies was assessed as low.

Conclusions

Respiratory hygiene, engineering, and environmental infection controls and personal respiratory protection interventions were associated with reduced transmission of M. tuberculosis and reduced tuberculosis disease in healthcare settings.

Latent tuberculosis infection in healthcare workers in low- and middle-income countries: an updated systematic review

Healthcare workers (HCWs) are at increased risk of latent tuberculosis (TB) infection (LTBI) and TB disease.We conducted an updated systematic review of the prevalence and incidence of LTBI in HCWs in low- and middle-income countries (LMICs), associated factors, and infection control practices. We searched MEDLINE, Embase and Web of Science (January 1, 2005-June 20, 2017) for studies published in any language. We obtained pooled estimates using random effects methods and investigated heterogeneity using meta-regression.85 studies (32 630 subjects) were included from 26 LMICs. Prevalence of a positive tuberculin skin test (TST) was 14-98% (mean 49%); prevalence of a positive interferon-γ release assay (IGRA) was 9-86% (mean 39%). Countries with TB incidence ≥300 per 100 000 had the highest prevalence (TST: pooled estimate 55%, 95% CI 41-69%; IGRA: pooled estimate 56%, 95% CI 39-73%). Annual incidence estimated from the TST was 1-38% (mean 17%); annual incidence estimated from the IGRA was 10-30% (mean 18%). The prevalence and incidence of a positive test was associated with years of work, work location, TB contact and job category. Only 15 studies reported on infection control measures in healthcare facilities, with limited implementation.HCWs in LMICs in high TB incidence settings remain at increased risk of acquiring LTBI. There is an urgent need for robust implementation of infection control measures.

Tuberculosis prevention knowledge, attitudes, and practices of primary health care nurses

AIM

Tuberculosis (TB) continues to challenge global health systems, especially in South Africa. Nurses are especially vulnerable to TB exposure, because of their prolonged front-line contact with infected patients-especially in primary health care (PHC) clinics. Their infection control practices, influenced by key factors such as knowledge and attitudes towards TB prevention, become an important consideration. The aim of the study was to (1) describe the TB prevention knowledge, attitudes, and practices of PHC nurses in a South African district and (2) explore moderating factors on TB prevention practices.

METHODS

A cross-sectional survey was undertaken at all 41 PHC facilities in Mangaung Metropolitan district, Free State province, South Africa, using self-administered questionnaires. Captured data were analysed to yield descriptive and multivariate statistics.

RESULTS

Results suggest several instances of inadequate TB prevention knowledge, attitudes, and practices. Good TB practice was predicted by TB attitudes and knowledge, and the relationship between TB prevention knowledge and practices was not moderated by training, attitudes, or nurse category.

CONCLUSION

Results echo previous indications that nurses often do not exhibit the desired knowledge, attitudes, and practices required to adequately protect themselves and others against TB and suggest further exploration towards understanding the influences on TB prevention practice among nurses.

Effectiveness of control measures to prevent occupational tuberculosis infection in health care workers: a systematic review

Background

A number of guideline documents have been published over the past decades on preventing occupational transmission of tuberculosis (TB) infection in health care workers (HCWs). However, direct evidence for the effectiveness of these controls is limited particularly in low-and middle-income (LMIC) countries. Thus, we sought to evaluate whether recommended administrative, environmental and personal protective measures are effective in preventing tuberculin skin test conversion among HCWs, and whether there has been recent research appropriate to LMIC needs.

Methods

Using inclusion criteria that included tuberculin skin test (TST) conversion as the outcome and longitudinal study design, we searched a number of electronic databases, complemented by hand-searching of reference lists and contacting experts. Reviewers independently selected studies, extracted data and assessed study quality using recommended criteria and overall evidence quality using GRADE criteria.

Results

Ten before-after studies were found, including two from upper middle income countries. All reported a decline in TST conversion frequency after the intervention. Among five studies that provided rates, the size of the decline varied, ranging from 35 to 100%. Since all were observational studies assessed as having high or unclear risk of bias on at least some criteria, the overall quality of evidence was rated as low using GRADE criteria.

Conclusion

We found consistent but low quality of evidence for the effectiveness of combined control measures in reducing TB infection transmission in HCWs in both high-income and upper-middle income country settings. However, research is needed in low-income high TB burden, including non-hospital, settings, and on contextual factors determining implementation of recommended control measures. Explicit attention to the reporting of methodological quality is recommended.

Trial registration

This systematic review was registered with PROSPERO in 2014 and its registration number is CRD42014009087.

Prevalence of and risk factors for tuberculosis among healthcare workers in Chinese tuberculosis facilities

Background

China is one of 22 countries with a high tuberculosis (TB) burden in the world. Healthcare workers (HCWs) have a high risk of contracting Mycobacterium tuberculosis infection due to insufficient infection control practices. We conducted a cross-sectional study to explore the prevalence of TB and its associated risk factors among HCWs in Chinese TB facilities.

Methods

Two hundred and forty-one TB facilities employing a total of 9663 HCWs were selected from 12 provinces in China to represent healthcare settings at the provincial, prefectural, and county levels. Structured questionnaires were used to collect information on TB infection control practices and HCWs in those facilities. Data was double entered into EpiData 3.1; TB prevalence and associated risk factors were analyzed using SPSS 21.0 with bivariate and multivariate regression models.

Results

The results showed that 71 HCWs had been diagnosed with TB, accounting for a prevalence of 760/100 000. The multivariate analysis showed that associated risk factors included belonging to the age group of 51 years and above (aOR: 6.17, 95% CI: 1.35–28.28), being a nurse (aOR = 3.09, 95% CI: 1.15–8.32), implementation of 0–9 items of management measures (aOR = 2.57, 95% CI: 1.37–4.80), and implementation of 0–1 items of ventilation measures (aOR = 2.42, 95% CI: 1.31–4.47).

Conclusion

This was the first national large sampling survey on TB prevalence among HCWs in China. It was found that the implementation of TB infection control practices in some facilities was poor. The TB prevalence in HCWs was higher than that in the general population. Therefore, TB infection control practices in Chinese medical facilities should be strengthened.

Electronic supplementary material

The online version of this article (10.1186/s40249-018-0407-6) contains supplementary material, which is available to authorized users.

Prevalence and risk factors for latent tuberculosis infection among healthcare workers in Nampula Central Hospital, Mozambique

BACKGROUND

Healthcare workers in high tuberculosis burdened countries are occupationally exposed to the tuberculosis disease with uncomplicated and complicated tuberculosis on the increase among them. Most of them acquire Mycobacterium tuberculosis but do not progress to the active disease - latent tuberculosis infection. The objective of this study was to assess the prevalence and risk factors associated with latent tuberculosis infection among healthcare workers in Nampula Central Hospital, Mozambique.

METHODS

This cross-sectional study of healthcare workers was conducted between 2014 and 2015. Participants (n = 209) were administered a questionnaire on demographics and occupational tuberculosis exposure and had a tuberculin skin test administered. Multivariate linear and logistic regression tested for associations between independent variables and dependent outcomes (tuberculin skin test induration and latent tuberculosis infection status).

RESULTS

The prevalence of latent tuberculosis infection was 34.4%. Latent tuberculosis infection was highest in those working for more than eight years (39.3%), those who had no BCG vaccination (39.6%) and were immunocompromised (78.1%). Being immunocompromised was significantly associated with latent tuberculosis infection (OR 5.97 [95% CI 1.89; 18.87]). Positive but non-significant associations occurred with working in the medical domain (OR 1.02 [95% CI 0.17; 6.37]), length of employment > eight years (OR 1.97 [95% CI 0.70; 5.53]) and occupational contact with tuberculosis patients (OR 1.24 [95% CI 0.47; 3.27]).

CONCLUSIONS

Personal and occupational factors were positively associated with latent tuberculosis infection among healthcare workers in Mozambique.

Perceived risk of tuberculosis infection among healthcare workers in Swaziland

BACKGROUND

The incidence of tuberculosis (TB) in the Kingdom of Swaziland is extremely high. How healthcare workers (HCWs) in Swaziland perceive infection control (IC) measures for preventing TB transmission is unclear. This study aimed to determine perceived risk of TB infection in relation to IC measures among HCWs in three institutions of Swaziland.

METHODS

A cross-sectional questionnaire survey was conducted in 2014. Demographic data and IC measures were collected from main and allied HCWs.

RESULTS

In total, 186 HCWs (19 doctors, 99 nurses, and 68 allied HCWs) were enrolled. The multivariate logistic regression analyses revealed that nurses (OR = 39.87, 95% CI = 2.721-584.3) and other HCWs (OR =99.34, 95% CI = 7.469-1321) perceived a higher TB infection risk than did doctors. Moreover, HCWs working for <4 years at the TB department perceived a lower TB infection risk (OR = 0.099, 95% CI = 0.022-0.453). Availability of N95 respirator masks (OR = 0.055, 95% CI = 0.005-0.586) and a designated sputum collection area (OR = 0.142, 95% CI = 0.037-0.545) also carried lower TB infection risks.

CONCLUSION

This study depicts the current status of IC measures for TB infection in a high prevalence country. The results suggest that HCWs perceived a greater TB infection risk at inadequate environmental IC measures.

Infection control and tuberculosis among health care workers in Viet Nam, 2009-2013: a cross-sectional survey

Background

Data on tuberculosis (TB) among health care workers (HCW) and TB infection control (TBIC) indicators are rarely available at national level. We assessed multi-year trends in notification data of TB among HCW and explored possible associations with TBIC indicators.

Methods

Notified TB incidence among HCW and 3 other TBIC indicators were collected annually from all 64 provincial and 3 national TB facilities in Vietnam. Time trends in TB notification between 2009 and 2013 were assessed using linear regression analysis. Multivariate regression models were applied to assess associations between the facility-specific 5-year notification rate and TBIC indicators.

Results

Forty-seven (70 %) of 67 facilities contributed data annually over five years; 15 reported at least one HCW with TB in 2009 compared to six in 2013. The TB notification rate dropped from 593 to 197 per 100,000 HCW (p_trend = 0.02).

Among 104 TB cases reported, 30 were employed at TB wards, 24 at other clinical wards, ten in the microbiology laboratory, six at the MDR-TB ward, and 34 in other positions.

The proportion of facilities with a TBIC plan and focal person remained relatively stable between 70 % and 84 %. The proportion of facilities providing personal protective equipment (PPE) to their staff increased over time. Facilities with a TBIC focal person were 7.6 times more likely to report any TB cases than facilities without a focal person.

Conclusions

The TB notification rates among HCW seemed to decrease over time. Availability of PPE increased over the same period. Appointing a TBIC focal person was associated with reporting of TB cases among HCW. It remains unclear whether TBIC measures helped in reduction of the TB notification rates in HCW.

Regular Sputum Check-Up for Early Diagnosis of Tuberculosis after Exposure in Healthcare Facilities

Background

The early diagnosis of patients with TB disease is critical after an outbreak of tuberculosis (TB) infection in healthcare facilities. In this study, we report a catastrophic TB outbreak in a psychiatric healthcare facility and analyze the role of regular sputum check-ups and other diagnostic tools to facilitate an early diagnosis.

Methods

Every exposed participant received regular sputum check-ups and chest X-rays (CXR) as part of the outbreak management protocol. We retrospectively analyzed data from the contact participants to identify risk factors for eventual TB development and investigated the diagnostic efficacy of regular sputum check-ups.

Results

Among 133 contact participants, 16 (12.0%) developed TB during the 4-year follow-up period. Low body-mass-index (BMI) (<21) (adjusted hazard ratio (aHR) 3.16, 95% confidence interval (CI) 1.11–8.98) and long duration of contact (>3 months) (aHR 8.70, 95% CI, 1.14–63.34) independently predicted the development of TB. Even though regular sputum check-ups required significant resources, they did facilitate the early identification of new TB cases among the contact participants. Regular sputum check-ups for high-risk patients based on BMI, contact duration and CXR findings may be a practical approach when compared with universal sputum follow-up, with a slightly decreased sensitivity but high positive likelihood ratio (88%, [95% CI, 62–98%] and 5.12, [95%CI, 3.30–7.95], respectively).

Conclusion

While regular sputum check-ups for all contact participants facilitated the early identification of cases after the outbreak of TB in the healthcare facility, regular sputum check-ups for high-risk patients might be an effective alternative in resource-limited settings.

Development of two artificial neural network models to support the diagnosis of pulmonary tuberculosis in hospitalized patients in Rio de Janeiro, Brazil

Pulmonary tuberculosis (PTB) remains a worldwide public health problem. Diagnostic algorithms to identify the best combination of diagnostic tests for PTB in each setting are needed for resource optimization. We developed one artificial neural network model for classification (multilayer perceptron-MLP) and another risk group assignment (self-organizing map-SOM) for PTB in hospitalized patients in a high complexity hospital in Rio de Janeiro City, using clinical and radiologic data collected from 315 presumed PTB cases admitted to isolation rooms from March 2003 to December 2004 (TB prevalence = 21.5 %). The MLP model included 7 variables-radiologic classification, age, gender, cough, night sweats, weight loss and anorexia. The sensitivity of the MLP model was 96.0 % (95 % CI ±2.0), the specificity was 89.0 % (95 % CI ±2.0), the positive predictive value was 72.5 % (95 % CI ±3.5) and the negative predictive value was 98.5 % (95 % CI ±0.5). The variable with the highest discriminative power was the radiologic classification. The high negative predictive value found in the MLP model suggests that the use of this model at the moment of hospital admission is safe. SOM model was able to correctly assign high-, medium- and low-risk groups to patients. If prospective validation in other series is confirmed, these models can become a tool for decision-making in tertiary health facilities in countries with limited resources.

Ensuring tuberculosis infection control to support greater involvement of people living with HIV in health care

Health care workers (HCWs) in high TB burden countries bear significant risks of being infected with Mycobacterium tuberculosis and developing TB disease through their work. In recent years, an increasing number of people living with HIV (PLHIV) are taking part in delivering HIV and other health services in resource-limited settings with high TB burden. The greater involvement of PLHIV in health service delivery has many beneficial consequences on individuals and health systems, however, the involvement creates considerable opportunities for them to be exposed to patients with infectious TB disease. Due to their immunodeficiency, PLHIV are far more likely to develop active TB following the infection. Available evidence and recently revised WHO policy guidance on TB infection control suggest simple, predominantly administrative control measures are feasible and effective in reducing the infection. Nevertheless, many countries are still at the early stage of developing infection control policies. We call for evidence-based infection control measures in order to ensure a safe working environment for PLHIV in support of their greater involvement in health care. More research is needed to strengthen knowledge on TB infection risks amongst PLHIV through involvement in service delivery, and optimal interventions to reduce it.

Implementation of tuberculosis infection control in health facilities in Mukono and Wakiso districts, Uganda

Background

Tuberculosis infection control (TBIC) is rarely implemented in the health facilities in resource limited settings. Understanding the reasons for low level of implementation is critical. The study aim was to assess TBIC practices and barriers to implementation in two districts in Uganda.

Methods

We conducted a cross-sectional study in 51 health facilities in districts of Mukono and Wakiso. The study included: a facility survey, observations of practices and eight focus group discussions with health workers.

Results

Quantitative: Only 16 facilities (31%) had a TBIC plan. Five facilities (10%) were screening patients for cough. Two facilities (4%) reported providing masks to patients with cough. Ventilation in the waiting areas was inadequate for TBIC in 43% (22/51) of the facilities. No facility possessed N95 particulate respirators.

Qualitative: Barriers that hamper implementation of TBIC elicited included: under-staffing, lack of space for patient separation, lack of funds to purchase masks, and health workers not appreciating the importance of TBIC.

Conclusion

TBIC measures were not implemented in health facilities in the two Ugandan districts where the survey was done. Health system factors like lack of staff, space and funds are barriers to implement TBIC. Effective implementation of TBIC measures occurs when the fundamental health system building blocks -governance and stewardship, financing, infrastructure, procurement and supply chain management are in place and functioning appropriately.

Classification and regression tree (CART) model to predict pulmonary tuberculosis in hospitalized patients

Background

Tuberculosis (TB) remains a public health issue worldwide. The lack of specific clinical symptoms to diagnose TB makes the correct decision to admit patients to respiratory isolation a difficult task for the clinician. Isolation of patients without the disease is common and increases health costs. Decision models for the diagnosis of TB in patients attending hospitals can increase the quality of care and decrease costs, without the risk of hospital transmission. We present a predictive model for predicting pulmonary TB in hospitalized patients in a high prevalence area in order to contribute to a more rational use of isolation rooms without increasing the risk of transmission.

Methods

Cross sectional study of patients admitted to CFFH from March 2003 to December 2004. A classification and regression tree (CART) model was generated and validated. The area under the ROC curve (AUC), sensitivity, specificity, positive and negative predictive values were used to evaluate the performance of model. Validation of the model was performed with a different sample of patients admitted to the same hospital from January to December 2005.

Results

We studied 290 patients admitted with clinical suspicion of TB. Diagnosis was confirmed in 26.5% of them. Pulmonary TB was present in 83.7% of the patients with TB (62.3% with positive sputum smear) and HIV/AIDS was present in 56.9% of patients. The validated CART model showed sensitivity, specificity, positive predictive value and negative predictive value of 60.00%, 76.16%, 33.33%, and 90.55%, respectively. The AUC was 79.70%.

Conclusions

The CART model developed for these hospitalized patients with clinical suspicion of TB had fair to good predictive performance for pulmonary TB. The most important variable for prediction of TB diagnosis was chest radiograph results. Prospective validation is still necessary, but our model offer an alternative for decision making in whether to isolate patients with clinical suspicion of TB in tertiary health facilities in countries with limited resources.

Barriers and motivators affecting tuberculosis infection control practices of Russian health care workers

SETTING

Five in-patient and out-patient tuberculosis (TB) care facilities in two regions of Russia.

OBJECTIVE

To identify barriers and motivators to the use of infection control measures among Russian TB health care workers.

DESIGN

In this qualitative study, a convenience sample of 96 health care workers (HCWs) was used to generate 15 homogeneous focus groups, consisting of physicians, nurses, and laboratory or support staff.

RESULTS

Barriers and motivators related to knowledge, attitudes and beliefs, and practices were identified. The three main barriers were 1) knowledge deficits, including the belief that TB was transmitted by dust, linens and eating utensils; 2) negative attitudes related to the discomfort of respirators; and 3) practices with respect to quality and care of respirators. Education and training, fear of infecting loved ones, and fear of punishment were the main motivators.

CONCLUSIONS

Our results point to the need for evaluation of current educational programs. Positive health promotion messages that appeal to fear might also be successful in promoting TB infection control. Individualized rewards based on personal motivators or group rewards that build on collectivist theory could be explored.

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.

Non-compliance with health surveillance is a matter of Biosafety: a survey of latent tuberculosis infection in a highly endemic setting

Objective This study aimed at identifying demographic, socio-economic and tuberculosis (TB) exposure factors associated with non-compliance with the tuberculin skin test, the management and prevention of non-compliance to the test. It was carried out in the context of a survey of latent TB infection among undergraduate students taking healthcare courses in two universities in Salvador, Brazil, a city highly endemic for TB. Methods This is a cross-sectional study of 1164 volunteers carried out between October 2004 and June 2008. Bivariate analysis followed by logistic regression was used to measure the association between non-compliance and potential risk factors through non-biased estimates of the adjusted OR for confounding variables. A parallel evaluation of occupational risk perception and of knowledge of Biosafety measures was also conducted. Results The non-compliance rate was above 40% even among individuals potentially at higher risk of disease, which included those who had not been vaccinated (OR 3.33; 95% CI 1.50 to 7.93; p=0.0018), those reporting having had contact with TB patients among close relatives or household contacts (p=0.3673), or those whose tuberculin skin test status was shown within the survey to have recently converted (17.3% of those completing the study). In spite of the observed homogeneity in the degree of Biosafety knowledge, and the awareness campaigns developed within the study focussing on TB prevention, the analysis has shown that different groups have different behaviours in relation to the test. Family income was found to have opposite effects in groups studying different courses as well as attending public versus private universities. Conclusions Although the data presented may not be directly generalisable to other situations and cultural settings, this study highlights the need to evaluate factors associated with non-compliance with routine testing, as they may affect the efficacy of Biosafety programs.

Occupational respiratory infections

PURPOSE OF REVIEW

In the last decade, descriptions of outbreaks of extensively drug-resistant strains of tuberculosis (TB) have increased concern about the nosocomial transmission of TB - a potentially life-threatening occupational respiratory infection. In addition, outbreaks of avian influenza caused by an H5N1 virus, severe acute respiratory syndrome caused by a coronavirus A and the recent pandemic caused by an H1N1 influenza virus have heightened concern about occupational infectious illnesses among workers in healthcare and agriculture.

RECENT FINDINGS

The last decade has witnessed extensive research into the modes, patterns, determinants and extent of transmission of these illnesses. The most important findings regarding risk, determinants and preventive measures of these occupational infections and recent guidelines are reviewed in this article.

SUMMARY

Administrative, personal and engineering measures to control respiratory infection are effective and should be implemented in healthcare facilities. The use of N95 personal respirators by healthcare workers who are caring for pulmonary TB and viral respiratory infections patients is strongly recommended. Vaccination against influenza (including H1N1) is effective and strongly recommended for healthcare workers. Ultraviolet germicidal irradiation is underused at present, despite good evidence of safety and efficacy in elimination of airborne respiratory infectious agents including TB.

Prevalence and risk factors for tuberculosis infection among hospital workers in Hanoi, Viet Nam

Background

Transmission of tuberculosis (TB) to health care workers (HCWs) is a global issue. Although effective infection control measures are expected to reduce nosocomial TB, HCWs' infection has not been assessed enough in TB high burden countries. We conducted a cross-sectional study to determine the prevalence of TB infection and its risk factors among HCWs in Hanoi, Viet Nam.

Methodology/Principal Findings

A total of 300 HCWs including all staff members in a municipal TB referral hospital received an interferon-gamma release assay (IGRA), QuantiFERON-TB Gold In-Tube^TM, followed by one- and two-step tuberculin skin test (TST) and a questionnaire-based interview. Agreement between the tests was evaluated by kappa statistics. Risk factors for TB infection were analyzed using a logistic regression model. Among the participants aged from 20 to 58 years (median = 40), prevalence of TB infection estimated by IGRA, one- and two-step TST was 47.3%, 61.1% and 66.3% respectively. Although the levels of overall agreement between IGRA and TST were moderate, the degree of agreement was low in the group with BCG history (kappa = 0.29). Working in TB hospital was associated with twofold increase in odds of TB infection estimated by IGRA. Increased age, low educational level and the high body mass index also demonstrated high odds ratios of IGRA positivity.

Conclusions/Significance

Prevalence of TB infection estimated by either IGRA or TST is high among HCWs in the hospital environment for TB care in Viet Nam and an infection control program should be reinforced. In communities with heterogeneous history of BCG vaccination, IGRA seems to estimate TB infection more accurately than any other criteria using TST.