Incidence of tuberculosis infection among New York State prison employees

Latent Tuberculosis Infection Diagnosis Using QuantiFERON-TB Gold Plus Kit Among Correctional Workers: A Cross-Sectional Study in Francisco Beltrão-PR, Brazil

Correctional workers form a high-priority group for tuberculosis control measures because of their high exposure and risk. This cross-sectional study conducted in April and May 2022 included 71 criminal police officers from the State Penitentiary of Francisco Beltrão-PR, Brazil. Their sociodemographic and laboratory data were collected. Latent tuberculosis infection (LTBI) was assessed using a QuantiFERON-TB Gold Plus in-tube test kit. Binary logistic regression was applied to calculate the odds ratios (ORs) and 95% confidence intervals (CI) of the LTBI predictors. The prevalence of LTBI was 22.6% (95% CI, 12.8-32.2%). Factors associated with LTBI were age > 43 years (OR, 0.18; 95% CI, 0.04-0.70; p < 0.014) and the use of medications (OR, 5.13; 95% CI, 1.40-18.87; p < 0.014). The prevalence was close to that estimated worldwide for LTBI in correctional workers, reinforcing the need for occupational health control measures consisting of regular screening and treatment of positive cases of latent infection among correctional workers to reduce the risk of illness and spread of infection in the penitentiary system and community.

Tuberculosis Outbreaks in State Prisons, United States, 2011-2019

Objectives. To understand the frequency, magnitude, geography, and characteristics of tuberculosis outbreaks in US state prisons. Methods. Using data from the National Tuberculosis Surveillance System, we identified all cases of tuberculosis during 2011 to 2019 that were reported as occurring among individuals incarcerated in a state prison at the time of diagnosis. We used whole-genome sequencing to define 3 or more cases within 2 single nucleotide polymorphisms within 3 years as clustered; we classified clusters with 6 or more cases during a 3-year period as tuberculosis outbreaks. Results. During 2011 to 2019, 566 tuberculosis cases occurred in 41 state prison systems (a median of 3 cases per state). A total of 19 tuberculosis genotype clusters comprising 134 cases were identified in 6 state prison systems; these clusters included a subset of 5 outbreaks in 2 states. Two Alabama outbreaks during 2011 to 2017 totaled 20 cases; 3 Texas outbreaks during 2014 to 2019 totaled 51 cases. Conclusions. Only Alabama and Texas reported outbreaks during the 9-year period; only Texas state prisons had ongoing transmission in 2019. Effective interventions are needed to stop tuberculosis outbreaks in Texas state prisons. (Am J Public Health. 2022;112(8):1170-1179. https://doi.org/10.2105/AJPH.2022.306864).

Incidence and prevalence of tuberculosis in incarcerated populations: a systematic review and meta-analysis

Background

Prisons are recognised as high-risk environments for tuberculosis, but there has been little systematic investigation of the global and regional incidence and prevalence of tuberculosis, and its determinants, in prisons. We did a systematic review and meta-analysis to assess the incidence and prevalence of tuberculosis in incarcerated populations by geographical region.

Methods

In this systematic review and meta-analysis, we searched MEDLINE, Embase, Web of Knowledge, and the LILACS electronic database from Jan 1, 1980, to Nov 15, 2020, for cross-sectional and cohort studies reporting the incidence of Mycobacterium tuberculosis infection, incidence of tuberculosis, or prevalence of tuberculosis among incarcerated individuals in all geographical regions. We extracted data from individual studies, and calculated pooled estimates of incidence and prevalence through hierarchical Bayesian meta-regression modelling. We also did subgroup analyses by region. Incidence rate ratios between prisons and the general population were calculated by dividing the incidence of tuberculosis in prisons by WHO estimates of the national population-level incidence.

Findings

We identified 159 relevant studies; 11 investigated the incidence of M tuberculosis infection (n=16 318), 51 investigated the incidence of tuberculosis (n=1 858 323), and 106 investigated the prevalence of tuberculosis (n=6 727 513) in incarcerated populations. The overall pooled incidence of M tuberculosis infection among prisoners was 15·0 (95% credible interval [CrI] 3·8–41·6) per 100 person-years. The incidence of tuberculosis (per 100 000 person-years) among prisoners was highest in studies from the WHO African (2190 [95% CrI 810–4840] cases) and South-East Asia (1550 [240–5300] cases) regions and in South America (970 [460–1860] cases), and lowest in North America (30 [20–50] cases) and the WHO Eastern Mediterranean region (270 [50–880] cases). The prevalence of tuberculosis was greater than 1000 per 100 000 prisoners in all global regions except for North America and the Western Pacific, and highest in the WHO South-East Asia region (1810 [95% CrI 670–4000] cases per 100 000 prisoners). The incidence rate ratio between prisons and the general population was much higher in South America (26·9; 95% CrI 17·1–40·1) than in other regions, but was nevertheless higher than ten in the WHO African (12·6; 6·2–22·3), Eastern Mediterranean (15·6; 6·5–32·5), and South-East Asia (11·7; 4·1–27·1) regions.

Interpretation

Globally, people in prison are at high risk of contracting M tuberculosis infection and developing tuberculosis, with consistent disparities between prisons and the general population across regions. Tuberculosis control programmes should prioritise preventive interventions among incarcerated populations.

Funding

US National Institutes of Health.

Guards in Prisons: A Risk Group for Latent Tuberculosis Infection

To determine the prevalence and incidence of LTBI among prison guards and to the risk factors associated with infection. Two male prisons in Medellín and Itaguí, Colombia. A cohort study was conducted in adult prison guards that consented to participate. Exclusion criteria included: previous or current active TB, or conditions that preclude TST administration. We screened 194 guards and completed 155 TST administrations. The prevalence of LTBI was 55.8% in prison one, and 39.1% in prison two. The risk factors associated with LTBI diagnosis included drug use at least once in a lifetime (PR: 1.75; 95% CI 1.42-2.15) and male sex (PR: 2.16; 95% CI 1.01-4.62). The cumulative incidence of TST conversion over 6 months was 3.2%. All conversions occurred in prison 1. Our findings suggest an occupational risk for LTBI prevalence and incidence among guards (different prevalence and incidence according to the prison they work).

Tuberculosis among correctional facility workers: A systematic review and meta-analysis

INTRODUCTION

Prison inmates can transmit tuberculosis, including drug-resistant strains, to correctional facility workers and the community. In this systematic literature review, we investigated the magnitude of active and latent tuberculosis infection (LTBI) and associated risk factors among correctional facility workers.

METHODS

We searched MEDLINE, EMBASE, LILACS, Cochrane CENTRAL, ISI Web of Science, CINAHL, and SCOPUS databases (January 1, 1989-December 31, 2017) for studies with the MeSH terms "prison" (and similar) AND "tuberculosis", without language restriction. We searched for gray literature in Google Scholar and conference proceedings. Stratified analyses according to tuberculosis burden were performed.

RESULTS

Of the 974 titles identified, 15 (nine good, six fair quality) fulfilled the inclusion criteria (110,393 correctional facility workers; six countries; 82,668 active tuberculosis; 110,192 LTBI). Pooled LTBI prevalence and incidence rates were 26% (12-42, I2 = 99.0%) and 2% (1-3, I2 = 98.6%), respectively. LTBI prevalence reached 44% (12-79, I2 = 99.0%) in high-burden countries. Active tuberculosis was reported only in low-burden countries (incidence range, 0.61-450/10,000 correctional facility workers/year). LTBI-associated risk factors included job duration, older age, country of birth, current tobacco smoking, reported contact with prisoners, and BCG vaccination.

CONCLUSION

Despite the risk of bias and high heterogeneity, LTBI was found to be prevalent in correctional facility workers, mainly in high-burden countries. LTBI risk factors suggest both occupational and community exposure. Active tuberculosis occurrence in low-burden countries suggests higher vulnerability from recent infection among correctional facility workers in these countries. Systematic surveillance and infection control measures are necessary to protect these highly vulnerable workers.

Tuberculosis and latent infection in employees of different prison unit types

OBJECTIVE

Estimate the prevalence of active tuberculosis and latent tuberculosis infection among the staff that is in contact and the staff that is not in contact with prisoners, and investigate factors associated with latent tuberculosis infection in this population.

METHODS

Observational cross-sectional study, conducted from 2012 to 2015, in employees of different prison units in the municipality of Franco da Rocha, SP. It consisted of the application of a questionnaire, application and reading of the tuberculin test, sputum smear microscopy, sputum culture, and radiological examination. The association between the qualitative variables was calculated by the Pearson's chi-squared test. The sociodemographic and clinical-epidemiological factors related to the latent tuberculosis infection were evaluated by the logistic regression with the odds ratios (OR) calculation and their respective intervals with 95% of confidence (95%CI).

RESULTS

A total of 1,059 employees were examined, 657 (62.0%) of prisons, 249 (23.5%) of CASA Foundation units and 153 (14.5%) of custodial and psychiatric treatment hospitals. The tuberculin test was applied and read for 945 (89.2%) professionals. Of these, 797 (84.3%) were contacts of detainees and 148 (15.7%) were not. Among prison staff, the factors associated with latent tuberculosis infection were: contact with detainee (OR = 2.12, 95%CI 1.21-3.71); male gender (OR = 1.97, 95%CI 1.19-3.27); between 30 and 39 years old (OR = 2.98, 95%CI 1.34-6.63), 40 to 49 years old (OR = 4.32, 95%CI 1.94-9.60), and 50 to 59 years old (OR = 3.98, 95%CI 1.68-9.43); nonwhite color or race (OR = 1.89, 95%CI 1.29-2.78); and smoker (OR = 1.64, 95%CI 1.05-2.55). There were no positive test on sputum smear microscopy and culture. Of the 241 (22.8%) professionals who underwent radiological examination, 48 (19.9%) presented alterations of which 11 were suspected of tuberculosis.

CONCLUSIONS

Prison employees who have direct contact with detainees are 2.12 times more likely to become infected with Mycobacterium tuberculosis in the work environment and consequently to become ill with tuberculosis and should be targeted for disease prevention and control.

Tuberculosis in Jails and Prisons: United States, 2002-2013

OBJECTIVES

To describe cases and estimate the annual incidence of tuberculosis in correctional facilities.

METHODS

We analyzed 2002 to 2013 National Tuberculosis Surveillance System case reports to characterize individuals who were employed or incarcerated in correctional facilities at time they were diagnosed with tuberculosis. Incidence was estimated with Bureau of Justice Statistics denominators.

RESULTS

Among 299 correctional employees with tuberculosis, 171 (57%) were US-born and 82 (27%) were female. Among 5579 persons incarcerated at the time of their tuberculosis diagnosis, 2520 (45%) were US-born and 495 (9%) were female. Median estimated annual tuberculosis incidence rates were 29 cases per 100 000 local jail inmates, 8 per 100 000 state prisoners, and 25 per 100 000 federal prisoners. The foreign-born proportion of incarcerated men 18 to 64 years old increased steadily from 33% in 2002 to 56% in 2013. Between 2009 and 2013, tuberculosis screenings were reported as leading to 10% of diagnoses among correctional employees, 47% among female inmates, and 42% among male inmates.

CONCLUSIONS

Systematic screening and treatment of tuberculosis infection and disease among correctional employees and incarcerated individuals remain essential to tuberculosis prevention and control.

Anti-TB drug resistance in Tanga, Tanzania: A cross sectional facility-base prevalence among pulmonary TB patients

OBJECTIVE

To determine the prevalence and risk factors associated with drug resistance tuberculosis (TB) at facility-base level in Tanga, Tanzania.

METHODS

A total of 79 Mycobacterium tuberculosis (MTB) isolates included in the study were collected from among 372 (312 new and 60 previously treated) TB suspects self-referred to four TB clinics during a prospective study conducted from November 2012 to January 2013. Culture and drug susceptibility test of the isolates was performed at the institute of medical microbiology and epidemiology of infectious diseases, University hospital, Leipzig, Germany. Data on the patient's characteristics were obtained from structured questionnaire administered to the patients who gave informed verbal consent. Unadjusted bivariate logistic regression analysis was performed to assess the risk factors for drug resistant-TB. The significance level was determined at P < 0.05.

RESULTS

The overall proportions of any drug resistance and MDR-TB were 12.7% and 6.3% respectively. The prevalence of any drug resistance and MDR-TB among new cases were 11.4% and 4.3% respectively, whereas among previously treated cases was 22.2% respectively. Previously treated patients were more likely to develop anti-TB drug resistance. There was no association between anti-TB drug resistances (including MDR-TB) with the risk factors analysed.

CONCLUSIONS

High proportions of anti-TB drug resistance among new and previously treated cases observed in this study suggest that, additional efforts still need to be done in identifying individual cases at facility-base level for improved TB control programmes and drug resistance survey should continuously be monitored in the country.

Infecção tuberculosa latente em profissionais contatos e não contatos de detentos de duas penitenciárias do estado de São Paulo, Brasil, 2008

INTRODUÇÃO: Para grupos de pessoas que permanecem confinadas, principalmente em presídios, a tuberculose sempre foi um grave problema de saúde, devido a sua transmissão respiratória, colocando em risco os profissionais que trabalham no sistema prisional, especialmente os contatos de detentos. OBJETIVO: Conhecer a prevalência de infecção pelo Mycobacterium tuberculosis entre os profissionais contatos e não contatos de detentos de duas penitenciárias do Estado de São Paulo. MÉTODOS: Este estudo consistiu na aplicação de um questionário individual; aplicação e leitura da prova tuberculínica; baciloscopia e cultura dos escarros, com posterior identificação e teste de sensibilidade às drogas antituberculose das cepas isoladas, no período de março a junho de 2008. RESULTADOS: Foram examinados 277 (48,3%) profissionais dos 574 existentes. Foram aplicados e lidos 248 (89,5%) testes tuberculínicos (PPD-RT23 - 2TU/0,1 mL), sendo que 194 foram em profissionais que trabalhavam diretamente com os detentos, ou seja, eram contatos e 54, em não contatos. Entre os contatos, 62,4% apresentaram enduração maior que 10 mm e entre os não contatos, 38,9% foram reatores ao teste tuberculínico. Não houve exame de escarro positivo na baciloscopia e na cultura, ou seja, não foi identificado nenhum caso de tuberculose doença entre os profissionais, no momento da pesquisa. CONCLUSÃO: Este estudo sugere que os profissionais que têm contato direto com os detentos, têm um risco maior de se infectar pelo M. tuberculosis e adoecer por tuberculose.

Tuberculosis incidence in prisons: a systematic review

BACKGROUND

Transmission of tuberculosis (TB) in prisons has been reported worldwide to be much higher than that reported for the corresponding general population.

METHODS AND FINDINGS

A systematic review has been performed to assess the risk of incident latent tuberculosis infection (LTBI) and TB disease in prisons, as compared to the incidence in the corresponding local general population, and to estimate the fraction of TB in the general population attributable (PAF%) to transmission within prisons. Primary peer-reviewed studies have been searched to assess the incidence of LTBI and/or TB within prisons published until June 2010; both inmates and prison staff were considered. Studies, which were independently screened by two reviewers, were eligible for inclusion if they reported the incidence of LTBI and TB disease in prisons. Available data were collected from 23 studies out of 582 potentially relevant unique citations. Five studies from the US and one from Brazil were available to assess the incidence of LTBI in prisons, while 19 studies were available to assess the incidence of TB. The median estimated annual incidence rate ratio (IRR) for LTBI and TB were 26.4 (interquartile range [IQR]: 13.0-61.8) and 23.0 (IQR: 11.7-36.1), respectively. The median estimated fraction (PAF%) of tuberculosis in the general population attributable to the exposure in prisons for TB was 8.5% (IQR: 1.9%-17.9%) and 6.3% (IQR: 2.7%-17.2%) in high- and middle/low-income countries, respectively.

CONCLUSIONS

The very high IRR and the substantial population attributable fraction show that much better TB control in prisons could potentially protect prisoners and staff from within-prison spread of TB and would significantly reduce the national burden of TB. Future studies should measure the impact of the conditions in prisons on TB transmission and assess the population attributable risk of prison-to-community spread. Please see later in the article for the Editors' Summary.

Prisons as social determinants of hepatitis C virus and tuberculosis infections

Effects of place or neighborhood--locations where individuals reside, shop, recreate, and work--have been widely studied as sources of environmental influences on individual behaviors, exposures, and physiology, as well as reference points for public health interventions. However, despite modern prisons' strong influence on the transmission and clinical outcomes of infectious diseases, custodial authorities and public health officials in many countries have yet to implement credible interventions to minimize the adverse impacts prison settings exert on the epidemiology of communicable diseases--particularly with respect to inmates. Among many vulnerable populations, prisons are evolving as one of the social institutions that determine their health status and health outcomes. This article highlights the effects of prisons in mediating the risk of hepatitis C virus and tuberculosis infections, as well as feasible interventions and policy approaches for limiting the deleterious consequences prisons exert on the transmission and clinical courses of these diseases.

Semiquantitative echocardiographic evaluation of intrapulmonary vascular dilatations: correlation with evaluation of shunt levels and pulmonary function parameters

OBJECTIVE

To correlate semiquantitative evaluation of intrapulmonary vascular dilatations (IPVD) with quantitative evaluation of shunt levels, as well as to describe clinical and pulmonary function findings in a sample of liver disease patients with IPVD.

METHODS

Patients presenting transthoracic echocardiography (TTE) positivity for IPVD underwent clinical evaluation, pulmonary function tests and pulmonary shunt quantification (scintigraphy with technetium-99m-labeled albumin macroaggregates and blood gas analysis after pure oxygen breathing).

RESULTS

A total of 28 liver cirrhosis patients were studied (mean age, 47.5 years; 60.7% were Child-Pugh class B). A 4-point, ascending scale was used as a measure of IPVD intensity, which was scored as 1, 2, 3 and 4, respectively, in 13 (46.4%), 9 (32.1%), 2 (7.1%) and 4 (14.3%) of the patients. Patients were divided into a low-intensity group (scores 1 and 2) and a high-intensity group (scores 3 and 4). The mean shunt assessed using scintigraphy was 14.9% in the sample as a whole and was lower in the low-intensity group (11.7% vs. 26.3%; p = 0.01). The mean shunt by blood gas analysis was higher in the high-intensity group (8.3% vs. 16.3%; p < 0.001). Mean PaO2 was lower in the high-intensity group. There was a negative correlation between DLCO and IPVD severity (r = -0.406, p = 0.01).

CONCLUSIONS

TTE is a safe, useful tool for assessing IPVD severity in liver disease patients. The IPVD intensity assessed using TTE correlated with the intrapulmonary shunt values obtained through the quantitative methods evaluated, as well as with pulmonary gas exchange abnormalities.

Prevalência de TB ativa e TB latente em internos de um hospital penal na Bahia

OBJETIVO: Estimar as prevalências de TB latente e TB ativa entre custodiados de um hospital penal na Bahia. MÉTODOS: Foram avaliados através de estudo de corte transversal com coleta prospectiva de dados 237 internos no Hospital Penal da Bahia entre julho de 2003 e abril de 2004. Um questionário padronizado foi preenchido por estudantes de medicina. Os indivíduos foram sistematicamente submetidos aos seguintes exames: teste tuberculínico, radiografia de tórax em incidência póstero-anterior, baciloscopia e cultura para micobactérias. Os eventos de interesse foram TB ativa e TB latente. RESULTADOS: A média de idade foi de 36,6 anos, sendo 89,9% homens. Tabagismo e alcoolismo foram relatados por 70.0% e 43.9% dos internos, respectivamente. História de tratamento para TB foi relatada por 11,3% dos indivíduos. Dos internos avaliados, 36,3% relataram tosse e 31,4%, expectoração. Outros sintomas menos frequentemente referidos foram astenia (26,2%), perda de peso (23,1%), inapetência (17,7%), febre (11,3%) e hemoptise (6,7%). Nenhum dos 86 internos testados apresentou sorologia anti-HIV positiva. Entre os 156 submetidos ao teste tuberculínico, a prevalência de TB latente foi de 61,5% (146 casos). Do total, 6 casos de TB ativa foram detectados (prevalência de 2,5%). A presença de tosse foi um determinante de TB ativa (razão de prevalência = 8,8; IC95%: 1,04-73,9; p = 0,025). CONCLUSÕES: A população de internos do Hospital Penal da Bahia tem altas prevalências de TB latente e ativa. Estes achados justificam a necessidade de implantação de políticas públicas especificamente direcionadas para o controle da TB nesta população

Discrimination of intact mycobacteria at the strain level: a combined MALDI-TOF MS and biostatistical analysis

New methodologies for surveillance and identification of Mycobacterium tuberculosis are required to stem the spread of disease worldwide. In addition, the ability to discriminate mycobacteria at the strain level may be important to contact or source case investigations. To this end, we are developing MALDI-TOF MS methods for the identification of M. tuberculosis in culture. In this report, we describe the application of MALDI-TOF MS, as well as statistical analysis including linear discriminant and random forest analysis, to 16 medically relevant strains from four species of mycobacteria, M. tuberculosis, M. avium, M. intracellulare, and M. kansasii. Although species discrimination can be accomplished on the basis of unique m/z values observed in the MS fingerprint spectrum, discrimination at the strain level is predicted on the relative abundance of shared m/z values among strains within a species. For the 16 mycobacterial strains investigated in the present study, it is possible to unambiguously identify strains within a species on the basis of MALDI-TOF MS data. The error rate for classification of individual strains using linear discriminant analysis was 0.053 using 37 m/z variables, whereas the error rate for classification of individual strains using random forest analysis was 0.023 using only 18 m/z variables. In addition, using random forest analysis of MALDI-TOF MS data, it was possible to correctly classify bacterial strains as either M. tuberculosis or non-tuberculous with 100% accuracy.

An unanswered health disparity: tuberculosis among correctional inmates, 1993 through 2003

OBJECTIVES

We sought to describe disparities and trends in tuberculosis (TB) risk factors and treatment outcomes between correctional inmate and noninmate populations.

METHODS

We analyzed data reported to the national TB surveillance system from 1993 through 2003. We compared characteristics between inmate and non-inmate men aged 15-64 years.

RESULTS

Of the 210976 total US TB cases, 3.8% (7820) were reported from correctional systems. Federal and state prison case rates were 29.4 and 24.2 cases per 100000 inmates, respectively, which were considerably higher than those in the noninmate population (6.7 per 100000 people). Inmates with TB were more likely to have at least 1 TB risk factor compared with noninmates (60.1% vs 42.0%, respectively) and to receive directly observed therapy (65.0% vs 41.0%, respectively); however, they were less likely to complete treatment (76.8% vs 89.4%, respectively). Among inmates, 58.9% completed treatment within 12 months compared with 73.2% of noninmates.

CONCLUSIONS

Tuberculosis case rates in prison systems remain higher than in the general population. Inmates with TB are less likely than noninmates to complete treatment.

American Thoracic Society/Centers for Disease Control and Prevention/Infectious Diseases Society of America: Controlling Tuberculosis in the United States

During 1993-2003, incidence of tuberculosis (TB) in the United States decreased 44% and is now occurring at a historic low level (14,874 cases in 2003). The Advisory Council for the Elimination of Tuberculosis has called for a renewed commitment to eliminating TB in the United States, and the Institute of Medicine has published a detailed plan for achieving that goal. In this statement, the American Thoracic Society (ATS), Centers for Disease Control and Prevention (CDC), and the Infectious Diseases Society of America (IDSA) propose recommendations to improve the control and prevention of TB in the United States and to progress toward its elimination. This statement is one in a series issued periodically by the sponsoring organizations to guide the diagnosis, treatment, control, and prevention of TB. This statement supersedes the previous statement by ATS and CDC, which was also supported by IDSA and the American Academy of Pediatrics (AAP). This statement was drafted, after an evidence-based review of the subject, by a panel of representatives of the three sponsoring organizations. AAP, the National Tuberculosis Controllers Association, and the Canadian Thoracic Society were also represented on the panel. This statement integrates recent scientific advances with current epidemiologic data, other recent guidelines from this series, and other sources into a coherent and practical approach to the control of TB in the United States. Although drafted to apply to TB-control activities in the United States, this statement might be of use in other countries in which persons with TB generally have access to medical and public health services and resources necessary to make a precise diagnosis of the disease; achieve curative medical treatment; and otherwise provide substantial science-based protection of the population against TB. This statement is aimed at all persons who advocate, plan, and work at controlling and preventing TB in the United States, including persons who formulate public health policy and make decisions about allocation of resources for disease control and health maintenance and directors and staff members of state, county, and local public health agencies throughout the United States charged with control of TB. The audience also includes the full range of medical practitioners, organizations, and institutions involved in the health care of persons in the United States who are at risk for TB.

Risk of Tuberculosis in Correctional Healthcare Workers

OBJECTIVE

The objective of this study was to determine the prevalence, incidence, and risk factors for occupational infection with tuberculosis among healthcare workers employed in correctional facilities.

METHODS

The authors conducted a self-administered survey, clinical interview, and tuberculin skin testing.

RESULTS

The overall tuberculin skin test point prevalence rate was 17.7%, the reactivity rate was 2.2%, and the annual incidence was 1.3%. At the multivariate level, after controlling for bacille Calmette-Guérin vaccination, only origin of birth remained significantly associated with prevalence of tuberculosis infection.

CONCLUSIONS

Although the prevalence of tuberculin reactivity was high in this population, the risk factors were predominantly demographic rather than occupational. Nevertheless, continued vigilance to control occupational exposure to this and other respiratory pathogens is warranted, given the potential for future outbreaks of tuberculosis, as well as other known and emerging airborne pathogens.

Prevalence of and risk factors associated with Mycobacterium tuberculosis infection in prisoners, North West Frontier Province, Pakistan

BACKGROUND

This cross-sectional study was conducted to assess the prevalence of and identify factors associated with latent Mycobacterium tuberculosis (MTB) infection in prisoners of North West Frontier Province (NWFP).

METHODS

A stratified random sampling technique was used to select a sample of 425 from a total of 6607 male prisoners aged 18-60 years from the five central prisons of NWFP, Pakistan (Peshawar, Dera Ismail Khan, Haripur, Kohat, and Mardan). The selected inmates were interviewed using a structured pre-tested questionnaire; a Mantoux tuberculin skin test (TST) was also performed. Latent MTB infection status of the prisoner was determined by the size of the induration of the TST in the presence/absence of a previous BCG scar.

RESULTS

Overall prevalence of latent MTB infection among prisoners was 48% (204/425). Using multiple logistic regression, a prisoner's age, educational level, smoking status, duration of current incarceration, and average accommodation area of 60 ft(2) or less in prison barracks were found to be statistically significant (P < 0.05) predictors of latent MTB infection.

CONCLUSION

The high prevalence of latent MTB infection as assessed by TST in prisoners requires immediate steps be taken to identify and confirm MTB infection, and to treat and counsel those found to be positive in this setting. Efforts to halt MTB transmission in prisons should include: routine screening of prisoners on entry using sputum smear and TST for diagnosis of tuberculosis (TB) and latent MTB infection, respectively. The isolation and treatment of TB positive prisoners and chemo-prophylactic treatment of TST positives, reduction of overcrowding, education regarding the harmful effects of smoking, and intensive monitoring of those serving longer prison terms may help reduce the MTB transmission in this setting and in the community at large.

Dying for work: The magnitude of US mortality from selected causes of death associated with occupation

BACKGROUND

Deaths due to occupational disease and injury place a heavy burden on society in terms of economic costs and human suffering.

METHODS

We estimate the annual deaths due to selected diseases for which an occupational association is reasonably well established and quantifiable, by calculation of attributable fractions (AFs), with full documentation; the deaths due to occupational injury are then added to derive an estimated number of annual deaths due to occupation.

RESULTS

Using 1997 US mortality data, the estimated annual burden of occupational disease mortality resulting from selected respiratory diseases, cancers, cardiovascular disease, chronic renal failure, and hepatitis is 49,000, with a range from 26,000 to 72,000. The Bureau of Labor Statistics estimates there are about 6,200 work-related injury deaths annually. Adding disease and injury data, we estimate that there are a total of 55,200 US deaths annually resulting from occupational disease or injury (range 32,200-78,200).

CONCLUSIONS

Our estimate is in the range reported by previous investigators, although we have restricted ourselves more than others to only those diseases with well-established occupational etiology, biasing our estimates conservatively. The underlying assumptions and data used to generate the estimates are well documented, so our estimates may be updated as new data emerges on occupational risks and exposed populations, providing an advantage over previous studies. We estimate that occupational deaths are the 8th leading cause of death in the US, after diabetes (64,751) but ahead of suicide (30,575), and greater than the annual number of motor vehicle deaths per year (43,501).

[Dental caries and socioeconomic conditions in the State of Paraná, Brazil, 1996]

The aim of this research was to determine the correlation between dental caries and socioeconomic conditions in the State of Paraná, Brazil. Caries prevalence was estimated for each city in the State by gathering data on the DMFT index (in 12-year-old schoolchildren) supplied by the State Health Department. Official socioeconomic data for the municipalities were also presented. Ordinary least squares regression analysis was performed, and significant correlation coefficients were observed between the dental caries index and various social development indicators. Maps highlighting the overlapping areas with poor outcomes for most of these variables were presented. The results showed a significantly lower DMFT index in cities with fluoridated water supply and a negative correlation between the caries index and the proportion of households with running water in cities with fluoridated water supply. This observation highlights the importance of fluoridated drinking water for the prevention of dental caries and as a measure to reduce the impact of socioeconomic inequalities on the prevalence of tooth decay.

Clinical and epidemiological observations of cutaneous tuberculosis in Larkana, Pakistan

BACKGROUND

Cutaneous tuberculosis is widespread in Pakistan but has not been fully documented. This study was conducted to determine the clinical pattern, nature and existence of the disease in Larkana, Sindh province, Pakistan.

METHODS

We are reporting 153 cases of patients with cutaneous tuberculosis who visited our department from 1996 to 1999. All cases were diagnosed at the clinic, and the biopsies were examined for histopathological evidence. The patients received three antituberculous treatments during a 9 month course.

RESULTS

Clinically, 63 (41.2%) cases of lupus vulgaris, 54 (35.3%) of scrofuloderma, 29 (19.59%) of lupus verrucosa cutis, six (3.92%) of tuberculosis cutis orificialis and one (0.64%) case of disseminated cutaneous tuberculosis were observed in our department from 1996 to 1999. All patients were aged between 3 and 50 years and had experienced the present complaints for 1 to 12 years. Sixty-nine (45.1%) cases were children aged under 10 years, 50 cases (37.25%) were aged between 10 and 20 years, and 27 cases (17.65%) were aged over 20 years. There was no considerable ratio difference of the disease between male and female patients. Histopathologically, all the specimens showed chronic granulomatous changes; the majority was infiltrated with epitheloid cells, langhans giant cells, plasma cells and other inflammatory cells, such as lymphocytes, eosinophils and neutrophils in ulcerated lesions. Increased numbers of mast cells were seen in upper and lower dermis in two-thirds of the specimens. Caseating necrosis was visible in half of the specimens while Ziehl-Neelsen stain was negative in all the sections.

CONCLUSIONS

The observed number of patients was moderately large, thus indicating a high incidence of cutaneous tuberculosis in Larkana. Lupus vulgaris, a form of cutaneous tuberculosis, was widespread in this area and prevalent in adults, while scrofuloderma was prevalent in children. Moreover, the existing rate of the disease was higher in children aged under 10 years and lower in adults. This indicates that children are more prone to this disease than adults.