Tuberculosis and homelessness in the United States, 1994-2003

Infectious Diseases Among People Experiencing Homelessness: A Systematic Review of the Literature in the United States and Canada, 2003-2022

Homelessness increases the risk of acquiring an infectious disease. We conducted a systematic review of the literature to identify quantitative data related to infectious diseases and homelessness. We searched Google Scholar, PubMed, and SCOPUS for quantitative literature published from January 2003 through December 2022 in English from the United States and Canada. We excluded literature on vaccine-preventable diseases and HIV because these diseases were recently reviewed. Of the 250 articles that met inclusion criteria, more than half were on hepatitis C virus or Mycobacterium tuberculosis. Other articles were on COVID-19, respiratory syncytial virus, Staphylococcus aureus, group A Streptococcus, mpox (formerly monkeypox), 5 sexually transmitted infections, and gastrointestinal or vectorborne pathogens. Most studies showed higher prevalence, incidence, or measures of risk for infectious diseases among people experiencing homelessness as compared with people who are housed or the general population. Although having increased published data that quantify the infectious disease risks of homelessness is encouraging, many pathogens that are known to affect people globally who are not housed have not been evaluated in the United States or Canada. Future studies should focus on additional pathogens and factors leading to a disproportionately high incidence and prevalence of infectious diseases among people experiencing homelessness.

Molecular epidemiology and drug sensitivity of Mycobacterium tuberculosis in homeless individuals in the Addis Ababa city, Ethiopia

Although homeless segment of the society could be the hotspots for tuberculosis (TB) transmission, there is little data on TB in homeless individuals in Ethiopia. The objective of this study was to investigate the molecular epidemiology and drug sensitivity of Mycobacterium tuberculosis (M. tuberculosis) isolated from homeless individuals in Addis Ababa, Ethiopia. The study was conducted on 59 M. tuberculosis isolates, which were recovered by the clinical screening of 5600 homeless individuals and bacteriological examination of 641 individuals with symptoms of pulmonary tuberculosis (PTB). Region of difference-9 (RD9) based polymerase-chain reaction (PCR), Spoligotyping and 24-loci Mycobacterial Interspersed Repetitive Unit-Variable Number Tandem Repeat (MIRU-VNTR) typing were used for genotyping of the isolates. In addition, drug sensitivity test was performed on the isolates using BD Bactec Mycobacterial Growth Inhibition Tube (MGIT) 960. Fifty-eight of the 59 isolates were positive by spoligotyping and spoligotyping International type (SIT) 53, SIT 37, and SIT 149 were the dominant spoligotypes; each consisting of 19%, 15.5%, and10.3% of the isolates, respectively. The majority of the isolates (89.7%) were members of the Euro-American (EA) major lineage. MIRU-VNTR identified Ethiopia_3, Delhi/CAS, Ethiopia_2, TUR, X-type, Ethiopia_H37Rv-like strain, Haarlem and Latin-American Mediterranean (LAM) sub lineages. The proportion of clustering was 77.6% (45/58) in spoligotyping while it was 39.7% (23/58) in 24-loci MIRU-VNTR typing. Furthermore, the proportion of clustering was significantly lowered to 10.3% (6/58) when a combination of spoligotyping and 24-loci MIRU-VNTRplus was used. The recent transmission index (RTI) recorded by spoligotyping, 24-loci MIRU-VNTR typing, and a combination of the two genotyping methods were 58.6%, 27.6% and 5.2%, respectively. Young age and living in groups were significantly associated with strain clustering (P < 0.05). The drug sensitivity test (DST) result showed 8.9% (4/58) of the isolates were resistant to one or more first line ant-TB drugs; but multidrug resistant isolate was not detected. Clustering and RTI could suggest the transmission of TB in the homeless individuals, which could suggest a similar pattern of transmission between homeless individuals and the general population. Hence, the TB control program should consider homeless individuals during the implementation of TB control program.

Diagnosis, Treatment, and Prevention of Tuberculosis Among People Experiencing Homelessness in the United States: Current Recommendations

OBJECTIVE

Tuberculosis (TB) is a public health problem, especially among people experiencing homelessness (PEH). The Advisory Council for the Elimination of Tuberculosis issued recommendations in 1992 for TB prevention and control among PEH. Our goal was to provide current guidelines and information in one place to inform medical and public health providers and TB programs on TB incidence, diagnosis, and treatment among PEH.

METHODS

We reviewed and synthesized diagnostic and treatment recommendations for TB disease and latent TB infection (LTBI) as of 2022 and information after 1992 on the magnitude of homelessness in the United States, the incidence of TB among PEH, the role of public health departments in TB case management among PEH, and recently published evidence.

RESULTS

In 2018, there were 1.45 million estimated PEH in the United States. During the past 2 decades, the incidence of TB was >10 times higher and the prevalence of LTBI was 7 to 20 times higher among PEH than among people not experiencing homelessness. TB outbreaks were common in overnight shelters. Permanent housing for PEH and the use of rapid TB diagnostic tests, along with isolation and treatment, reduced TB exposure among PEH. The use of direct observation enhanced treatment adherence among PEH, as did involvement of social workers to help secure shelter, food, safety, and treatment for comorbidities, especially HIV and substance use disorders. Testing and treatment for LTBI prevented progression to TB disease, and shorter LTBI regimens helped improve adherence. Federal agencies and the National Health Care for the Homeless Council have helpful resources.

CONCLUSION

Improvements in TB diagnosis, treatment, and prevention among PEH are possible by following existing recommendations and using client-centered approaches.

Prevalence of pulmonary tuberculosis in homeless individuals in the Addis Ababa City, Ethiopia

Background

Homeless individuals are at a high risk of infection with Mycobacterium tuberculosis (M. tuberculosis) as compared to the general population. The number of homeless individuals has been increasing in Addis Ababa City during the last three decades due to the migration of rural inhabitants to the City for better living conditions. The objective of this study was to estimate the prevalence of pulmonary tuberculosis (PTB) and evaluate associated risk factors in homeless individuals in Addis Ababa City.

Methods

A total of 5,600 homeless individuals were screened for PTB symptoms using WHO guideline between February 2019 and December 2020. Sputum samples were cultured from individuals with symptoms of PTB for mycobacterial isolation. Logistic regression analysis was used to identify factors associated with PTB.

Results

The prevalence of bacteriologically confirmed cases was 1.1% (59/5,600) or 10.54 per 1000 population. Multinomial logistic regression analysis showed that being homeless for more than 5 years, body mass index (BMI) &lt; 18.5, smoking cigarette, living in a group of more than five individuals, close contact with chronic coughers, imprisonment and HIV infection were significantly associated with the prevalence of PTB in homeless individuals (P &lt; 0.05).

Conclusion

In conclusion, the result of this study indicated that the prevalence of PTB in homeless individuals was higher than the prevalence of PTB in the general population of Addis Ababa City requiring for the inclusion of the homeless individuals in the TB control program.

Wearable microfluidic-based e-skin sweat sensors

Electronic skins (e-skins) are soft (deformable and stretchable) state-of-the-art wearable devices that emulate the attributes of human skin and act as a Human-Machine Interface (HMI). Recent advances in e-skin for real-time detection of medical signals such as pulse, temperature, electromyogram (EMG), electroencephalogram (EEG), electrooculogram (EOG), electrocardiogram (ECG), and other bioelectric signals laid down an intelligent foundation for early prediction and diagnosis of diseases with a motive of reducing the risk of the ailment reaching to the end stage. In particular, sweat testing has been employed in diverse applications ranging from medical diagnosis of diabetes, cystic fibrosis, tuberculosis, blood pressure, and autonomic neuropathy to evaluating fluid and electrolyte balance in athletes. Typically, sweat testing techniques are done by trained experts and require off-body measurements, which prevent individuals from de-coding health issues quickly and independently. With the onset of soft electronics, wearable sweat sensors overcome this disadvantage via in situ sweat measurements with real-time feedback, timely diagnosis, creating the potential for preventive care and treatment. Over the past few decades, wearable microfluidic-based e-skin sweat sensors have paved a new way, promising sensing interfaces that are highly compatible with arranging medical and electronic applications. The present review highlights the recent research carried out in the microfluidic-based wearable sweat sensors with a critical focus on real-time sensing of lactate, chloride, and glucose concentration; sweat rate, simultaneously with pH, and total sweat loss for preventive care, timely diagnosis, and point-of-care health and fitness monitoring.

Multipronged Approach to Controlling a Tuberculosis Outbreak Among Persons Experiencing Homelessness

In May 2009, the Marion County Public Health Department in Indiana declared a tuberculosis (TB) outbreak among persons experiencing homelessness in Marion County, began active case finding to detect additional cases, and formed a TB outbreak response team to plan and coordinate outbreak activities. Outbreak-associated cases had 1 of 2 outbreak genotypes and either reported experiencing homelessness themselves or had an epidemiologic link to a shelter or a person experiencing homelessness. The last of 53 outbreak-associated cases was detected in 2019 after more than 2 years without a case. The Marion County Public Health Department continues to address TB-related issues and implement prevention measures at homeless shelters and among persons experiencing homelessness in 2019. This example, in addition to other published guidance, can be used by jurisdictions to plan and implement their own TB outbreak prevention and response activities among persons experiencing homelessness.

Responding to pandemics and other disease outbreaks in homeless populations: A review of the literature and content analysis

Considering the recent COVID-19 pandemic, we recognised a lack of synthesis amongst the available literature pertaining to the intersections of homelessness and pandemic response and planning. Therefore, the purpose of this review was to identify relevant peer-reviewed literature in this area to thematically produce evidence-based recommendations that would inform community planning and response amongst homeless populations. Although this review is inspired by the COVID-19 pandemic, our intention was to produce relevant recommendations to for all current and future outbreaks and pandemics more generally. Our search criteria focused on pandemics and rapid-spread illnesses such as contagious respiratory diseases with contact spread and with an emphasis on individuals experiencing homelessness. Content analysis methods were followed to extract and thematically synthesise key information amongst the 223 articles that matched our search criteria between the years of 1984 and 2020. Two reviewers were assigned to the screening process and used Covidence and undertook two rounds of discussion to identify and finalise themes for extraction. This review illustrates that the current breadth of academic literature on homeless populations has thus far focused on tuberculosis (TB) rather than diseases that are more recent and closely related to COVID-19-such as Severe Acute Respiratory Syndrome (SARS) or H1N1. Our thematic content analysis revealed six themes that offer tangible and scalable recommendations which include (1) education and outreach, (2) adapting structure of services, (3) screening and contract tracing, (4) transmission and prevention strategies, (5) shelter protocols and (6) treatment, adherence and vaccination. The breadth and depth of reviews such as these are dependent on the quantity and quality of the available literature. Therefore, the limited existing literature outside of tuberculosis specific to homelessness in this review illustrates a need for more academic research into the intersections of pandemics and homelessness-particularly for evaluations of response and planning. Nonetheless, this review offers timely considerations for pandemic response and planning amongst homeless populations during the current COVID-19 pandemic and can facilitate future research in this area.

High burden of tuberculosis infection and disease among people receiving medication-assisted treatment for substance use disorder in Tanzania

OBJECTIVE

To determine the prevalence of tuberculosis (TB) disease and infection as well as incident TB disease among people who use drugs (PWUD) attending Medication Assisted Treatment (MAT) clinics in Dar-es-Salaam, Tanzania.

METHODS

In this prospective cohort study, a total of 901 consenting participants were enrolled from November 2016 to February 2017 and a structured questionnaire administered to them through the open data kit application on android tablets. Twenty-two months later, we revisited the MAT clinics and reviewed 823 of the 901 enrolled participant's medical records in search for documentation on TB disease diagnosis and treatment. Medical records reviewed included those of participants whom at enrolment were asymptomatic, not on TB disease treatment, not on TB preventive therapy and those who had a documented tuberculin skin test (TST) result.

RESULTS

Of the 823 medical records reviewed 22 months after enrolment, 42 had documentation of being diagnosed with TB disease and initiated on TB treatment. This is equivalent to a TB disease incidence rate of 2,925.2 patients per 100,000 person years with a total follow up time of 1,440 person-years. At enrolment the prevalence of TB disease and TB infection was 2.6% and 54% respectively and the HIV prevalence was 44% and 16% among females and males respectively.

CONCLUSION

PWUD attending MAT clinics bear an extremely high burden of TB and HIV and are known to have driven TB epidemics in a number of countries. Our reported TB disease incidence is 12 times that of the general Tanzanian incidence of 237 per 100,000 further emphasizing that this group should be prioritized for TB screening, testing and treatment. Gender specific approaches should also be developed as female PWUDs are markedly more affected with HIV and TB disease than male PWUDs.

Tuberculosis in the street population: a systematic review

OBJECTIVE

To analyze evidence of the occurrence of tuberculosis in people living on the streets provided by the literature.

METHOD

Systematic review conducted in the databases PubMed, EMBASE, LILACS, and SciELO electronic library. Analysis of the empirical material was guided by Hermeneutics. The main themes which give shape to the association between tuberculosis and street population were sought to be understood.

RESULTS

Initially, 343 articles were identified, but only seven met the eligibility criteria. The literature shows that homeless people with tuberculosis presented unfavorable treatment outcomes when compared to the population with fixed residence. Some of the associated reasons were abusive consumption of alcohol and other drugs and associated diseases, such as human immunodeficiency virus and others.

CONCLUSION

Despite the importance of this theme, analysis of the scientific production has provided evidence of the need for studies aimed not only at comprehending the occurrence of disease in this vulnerable group, but specially ways of fighting it.

Opioid Use Disorder and Associated Infectious Disease: The Role of the Laboratory in Addressing Health Disparities

BACKGROUND

Opioid use disorder, defined as a pattern of problematic opioid use leading to clinically significant impairment, has resulted in considerable morbidity and mortality throughout the world. This is due, at least in part, to the marginalized status of patients with opioid use disorder, limiting their access to appropriate laboratory testing, diagnosis, and treatment. Infections have long been associated with illicit drug use and contribute considerably to morbidity and mortality. However, barriers to testing and negative stigmas associated with opioid use disorder present unique challenges to infectious disease testing in this patient population.

CONTENT

This review addresses the associations between opioid use disorder and infectious organisms, highlighting the health disparities encountered by patients with opioid use disorder, and the important role of laboratory testing for diagnosing and managing these patients.

SUMMARY

Infections are among the most frequent and adverse complications among patients with opioid use disorder. As a result of health disparities and systemic biases, patients that misuse opioids are less likely to receive laboratory testing and treatment. However, laboratories play a crucial in identifying patients that use drugs illicitly and infections associated with illicit drug use.

Impact of Targeted Local Interventions on Tuberculosis Awareness and Screening Among Persons Experiencing Homelessness During a Large Tuberculosis Outbreak in Atlanta, Georgia, 2015-2016

OBJECTIVES

Tuberculosis (TB) outbreaks disproportionately affect persons experiencing homelessness (PEH) in the United States. During 2014-2016, a resurgent TB outbreak occurred among PEH in Atlanta, Georgia. To control the outbreak, citywide policies and educational interventions were implemented in January 2015. Policy changes standardized and enforced TB screening requirements for PEH in homeless shelters. Educational campaigns informed PEH of the outbreak and encouraged TB screening. We evaluated factors associated with, and the effect policy changes and educational interventions had on, TB screening and awareness among PEH in Atlanta.

METHODS

Questions related to TB screening and awareness of the outbreak were added to an annual US Department of Housing and Urban Development survey of PEH in Atlanta in 2015 (n = 296 respondents) and 2016 (n = 1325 respondents). We analyzed the 2016 survey data to determine characteristics associated with outcomes.

RESULTS

From 2015 to 2016, reported TB screening increased from 81% to 86%, and awareness of the TB outbreak increased from 68% to 75%. In 2016, sheltered PEH were significantly more likely than unsheltered PEH to report being evaluated for TB in the previous 6 months (prevalence odds ratio [pOR] = 3.18; 95% confidence interval [CI], 2.28-4.47) and to report being aware of the TB outbreak (pOR = 4.00; 95% CI, 2.89-5.55).

CONCLUSIONS

Implementation of required TB screening and educational interventions may reduce the incidence and severity of TB outbreaks among PEH in other communities. Furthermore, the annual survey of PEH offers an opportunity to collect data to better inform practices and policies.

Homelessness and HIV: A Combination Predictive of Poor Tuberculosis Treatment Outcomes and in Need of Innovative Strategies to Improve Treatment Completion

Antioquia Department is the state with the highest burden of tuberculosis (TB) in Colombia. Our aim was to determine the risk factors associated with unsuccessful TB treatment in HIV-seropositive and homeless persons, compared with non-HIV-infected and non-homeless persons with TB. We conducted a retrospective cohort study using observational, routinely collected health data from all drug-susceptible TB cases in homeless and/or HIV-seropositive individuals in Antioquia from 2014 to 2016. Unsuccessful TB treatment was defined as individuals having been lost to follow-up, having died, or treatment failure occurrence during the study period. Successful treatment was defined as cure of TB or treatment completion according to the WHO definitions. We identified 544 homeless persons with TB (432 HIV- and 112 HIV+), 835 HIV+ persons with TB and non-homeless, and 5,086 HIV-/non-homeless people with TB. Unsuccessful treatment rates were 19.3% in HIV-/non-homeless persons, 37.4% in non-homeless HIV+ patients, 61.5% in homeless HIV- patients, and 70.3% in homeless HIV+ patients; all rates fall below End TB strategy targets. More than 50% of homeless patients were lost to follow-up. Risk factors associated with unsuccessful treatment were HIV seropositivity, homelessness, male gender, age ≥ 25 years, noncontributory-type health insurance, TB diagnosis made during hospitalization, and previous treatment for TB. These results highlight the challenge of treating TB in the homeless population. These findings should put an onus on TB programs, governments, clinicians, and others involved in the collaborative care of TB patients to pursue innovative strategies to improve treatment success in this population.

Homelessness and Mortality Among Persons With Tuberculosis in Texas, 2010-2017

OBJECTIVE

A disproportionate number of tuberculosis cases and tuberculosis deaths occur among persons experiencing homelessness in the United States. Our objective was to identify risks for homelessness and death during mycobacterial treatment among persons experiencing homelessness with tuberculosis in Texas.

METHODS

Using data from the Centers for Disease Control and Prevention's TB Genotyping Information Management System, we evaluated data on demographic, laboratory, and clinical characteristics of persons experiencing homelessness in Texas during the year before tuberculosis diagnosis, from January 1, 2010, through December 31, 2017.

RESULTS

Of 10 130 new diagnoses of tuberculosis among persons living in Texas during the study period, 543 were reported as being homeless in the year before tuberculosis diagnosis. The odds of dying during treatment were 2.26 (95% confidence interval, 1.68-3.03) times higher among persons with tuberculosis experiencing homelessness than among persons with tuberculosis living in homes.

CONCLUSIONS

Our findings indicate that persons experiencing homelessness bear an undue burden of tuberculosis mortality in Texas. The burden may be related to poorer health caused by poverty stressors, comorbidities, or lack of access to health care.

Treatment of latent Mycobacterium tuberculosis infection with 12 once weekly directly-observed doses of isoniazid and rifapentine among persons experiencing homelessness

Objectives

To investigate treatment outcomes and associated characteristics of persons experiencing homelessness who received 12-weekly doses of directly observed isoniazid and rifapentine (3HP/DOT) treatment for latent TB infection (LTBI).

Methods

Among homeless persons treated with 3HP/DOT during July 2011 –June 2015 in 11 U.S. TB programs, we conducted descriptive analyses of observational data, and identified associations between sociodemographic factors and treatment outcomes. Qualitative interviews were conducted to understand programmatic experiences.

Results

Of 393 persons experiencing homelessness (median age: 50 years; range: 13–74 years), 301 (76.6%) completed treatment, 55 (14.0%) were lost to follow-up, 18 (4.6%) stopped because of an adverse event (AE), and 19 (4.8%) stopped after relocations or refusing treatment. Eighty-one (20.6%) had at least one AE. Persons aged ≥65 were more likely to discontinue treatment than persons aged 31–44 years. Programs reported difficulty in following up with persons experiencing homelessness because of relocations, mistrust, and alcohol or drug use.

Conclusions

This study demonstrates the feasibility of administering the 3HP/DOT LTBI regimen to persons experiencing homelessness, a high-risk population.

Public Health and Vulnerable Populations: Morbidity and Mortality Among People Ever Incarcerated in New York City Jails, 2001 to 2005

The health of people ever incarcerated in New York City (NYC) jails during 2001 to 2005 was characterized by matching jail, shelter, mortality, sexually transmitted infection, HIV, and tuberculosis (TB) data from the NYC Departments of Health and Mental Hygiene, Correction, and Homeless Services. Compared with nonincarcerated people and those living in the lowest income NYC neighborhoods, those ever incarcerated had higher HIV prevalence and HIV case rates. Ever-incarcerated females also had higher rates of gonorrhea and syphilis than nonincarcerated females. Ever-incarcerated people who used the single adult homeless shelter system had higher HIV, gonorrhea, and TB case rates and all-cause mortality rates than ever-incarcerated people without shelter use, when adjusting for other variables. People ever incarcerated in NYC jails are at risk for conditions of public health importance. Sex-specific jail- and community-based interventions are needed.

Whole transcriptomic and proteomic analyses of an isogenic M. tuberculosis clinical strain with a naturally occurring 15 Kb genomic deletion

Tuberculosis remains one of the most difficult to control infectious diseases in the world. Many different factors contribute to the complexity of this disease. These include the ability of the host to control the infection which may directly relate to nutritional status, presence of co-morbidities and genetic predisposition. Pathogen factors, in particular the ability of different Mycobacterium tuberculosis strains to respond to the harsh environment of the host granuloma, which includes low oxygen and nutrient availability and the presence of damaging radical oxygen and nitrogen species, also play an important role in the success of different strains to cause disease. In this study we evaluated the impact of a naturally occurring 12 gene 15 Kb genomic deletion on the physiology and virulence of M. tuberculosis. The strains denominated ON-A WT (wild type) and ON-A NM (natural mutant) were isolated from a previously reported TB outbreak in an inner city under-housed population in Toronto, Canada. Here we subjected these isogenic strains to transcriptomic (via RNA-seq) and proteomic analyses and identified several gene clusters with differential expression in the natural mutant, including the DosR regulon and the molybdenum cofactor biosynthesis genes, both of which were found in lower abundance in the natural mutant. We also demonstrated lesser virulence of the natural mutant in the guinea pig animal model. Overall, our findings suggest that the ON-A natural mutant is less fit to cause disease, but nevertheless has the potential to cause extended transmission in at-risk populations.

Diagnostic dilemma of pulmonary tuberculosis among adults with severe mental illness in Beijing, China

Background

Although the prevalence of tuberculosis has decreased significantly over the past decades, the certain populations with mental illness are at increased risk for tuberculosis infection and transmission. However, no studies have examined the performance of different laboratory examination methods among people with severe mental illness in China.

Methods

In this study, we firstly performed a retrospective study to evaluate the feasibility of three routine laboratory methods, including sputum microscopy, solid culture and GeneXpert, to diagnose tuberculosis patients with mental illness.

Results

During August 2010 and March 2013, a total of 251 TB patients based on clinical and radiographic criteria with severe mental illness were enrolled in this study. The majority of patients was homeless (97/251, 38.6%), and the other 62 (24.7%) and 92 (36.7%) were from urban and rural region, respectively. The most frequently diagnosed mental illness was schizophrenia, accounting for 84.1% (211/251) of patients available for analysis. In addition, the laboratory received 753 sputum samples collected from these 251 TB patients, of which 76.0% (572/753) of samples were classified as salivary sputum, which were unqualified for microscopy and culture. When the test results were analyzed by patients, the positive numbers of TB patients detected by sputum microscopy, solid culture and GeneXpert were 3 (1.2%), 5 (2.0%) and 5 (2.0%), respectively.

Conclusions

In conclusion, our findings reveal that the current laboratory examinations based on sputum samples seem not to be suitable for the diagnosis of active TB in the persons with severe mental illness. The products using a non-invasive specimen such as urine deserve further evaluation, which may generate benefit for the early diagnosis of TB in this special population.

Smear positive pulmonary tuberculosis and associated factors among homeless individuals in Dessie and Debre Birhan towns, Northeast Ethiopia

BACKGROUND

Tuberculosis (TB) remains one of the globe's deadliest communicable diseases. The homeless individuals are at high risk to acquire TB and multi-drug resistant TB (MDR-TB), because of their poor living conditions and risky behaviors. Tuberculosis and MDR-TB in the homeless individuals can pose a risk to entire communities. However, the magnitude of the problem is not known in Ethiopia. Therefore, the aim of this study was to determine the prevalence and associated factors of smear positive pulmonary TB (PTB) and MDR-TB among homeless individuals in Dessie and Debre Birhan towns, Northeast Ethiopia.

METHODS

A community based cross-sectional study design was conducted from September 2014 to June 2015. Using an active screening with cough of ≥2 weeks, 351 TB suspects homeless individuals were participated in this study. Data were collected by using pre-tested and structured questionnaire. Spot-morning-spot sputum sample was collected and examined for acid-fast bacilli (AFB) using fluorescence microscopy by Auramine O staining technique. All AFB positive sputum was further analyzed by GeneXpert for detection of Mycobacterium tuberculosis complex and rifampicin resistant gene. Univariate and multivariate logistic regressions were applied to identify factors associated with smear positive PTB and P value <0.05 was considered as statistically significant.

RESULTS

The prevalence of smear positive PTB was 2.6 % (95 % CI 1.3-5) among TB suspect homeless individuals. Extrapolation of this study finding implies that there were 505 smear positive PTB per 100,000 homeless individuals. All smear positive PTB sputum specimens were further analyzed by GeneXpert assay, the assay confirmed that all were positive for MTBC but none were resistant to RIF or MDR. Smoking cigarette regularly for greater than 5 years (AOR 10.1, 95 % CI 1.1, 97.7), body mass index lower than 18.5 (AOR 6.9, 95 % CI 1.12, 41.1) and HIV infection (AOR 6.8, 95 % CI 1.1, 40.1) were significantly associated with smear positive PTB.

CONCLUSION

The prevalence of smear positive PTB among TB suspect homeless individuals was 2.6 %. Among smear positive PTB, prevalence of HIV co-infection was very high 5 (55.5 %). Smoking cigarette regularly for greater than 5 years, BMI lower than 18.5 and HIV infection were factors associated with smear positive PTB. Special emphasis is needed for homeless individuals to exert intensive effort to identify undetected TB cases to limit the circulation of the disease into the community.

The impact of being homeless on the unsuccessful outcome of treatment of pulmonary TB in São Paulo State, Brazil

BACKGROUND

Tuberculosis (TB) is a major public health problem requiring complex treatment, the success of which depends on biological, social, and institutional factors. São Paulo State (SPS), in Brazil, has a high TB burden. Because of high socioeconomic heterogeneity and chaotic urbanisation, homelessness might play an important role in the TB burden in SPS. Our aim was to determine the association between homelessness and outcome of treatment of pulmonary TB (PTB) in SPS.

METHODS

A historical cohort from the routine SPS TB database for 2009-2013 was analysed. The study population was newly diagnosed adult patients with PTB. Homelessness was ascertained at notification or when treatment started. Our outcome was unsuccessful outcome of treatment. We used logistic regression to adjust for potential confounders and multiple imputation for missing data.

RESULTS

We analysed 61,817 patients; 1726 (2.8 %, 95%CI 2.7-2.9 %) were homeless. Homeless patients were concentrated in bigger cities, were more frequently middle-aged males, had black/brown skin colour, and had received less education (P < 0.001, for all). Alcohol and drug use was three times more frequent in homeless patients (43.2 % vs 14.4 %, 30.2 % vs. 9.4 %, P < 0.001, respectively). HIV testing was less common among the homeless, of whom 17.3 % were HIV positive compared with 8.5 % among the not homeless population (P < 0.001). Microbiologic confirmation was more frequent among the homeless (91.6 % vs. 84.8 %, P < 0.001). Unsuccessful outcome of treatment was 57.3 % among the homeless and 17.5 % among the not homeless (OR = 6.32, 95%CI 5.73-6.97, P < 0.001), mainly due to loss to follow-up (39 %) and death (10.5 %). After full-adjustment for potential confounders, homelessness remained strongly associated with lower treatment success (aOR = 4.96, 95 % CI 4.27-5.76, P < 0.001). HIV status interacted with homelessness: among HIV-infected patients, the aOR was 2.45 (95%CI 1.90-3.16, Pinteraction < 0.001). The population attributable fraction for the joint effect of homelessness, alcohol and drug use was almost 20 %.

CONCLUSIONS

Confirming our hypothesis, homelessness led to a marked reduction in the successful treatment of newly diagnosed pulmonary tuberculosis. Homelessness and associated conditions were important contributors to lack of treatment success in pulmonary tuberculosis in São Paulo. A multifaceted intervention must be implemented to target this vulnerable population.

Marked microevolution of a unique Mycobacterium tuberculosis strain in 17 years of ongoing transmission in a high risk population

The transmission and persistence of Mycobacterium tuberculosis within high risk populations is a threat to tuberculosis (TB) control. In the current study, we used whole genome sequencing (WGS) to decipher the transmission dynamics and microevolution of M. tuberculosis ON-A, an endemic strain responsible for an ongoing outbreak of TB in an urban homeless/under-housed population. Sixty-one M. tuberculosis isolates representing 57 TB cases from 1997 to 2013 were subjected to WGS. Sequencing data was integrated with available epidemiological information and analyzed to determine how the M. tuberculosis ON-A strain has evolved during almost two decades of active transmission. WGS offers higher discriminatory power than traditional genotyping techniques, dividing the M. tuberculosis ON-A strain into 6 sub-clusters, each defined by unique single nucleotide polymorphism profiles. One sub-cluster, designated ON-A^NM (Natural Mutant; 26 isolates from 24 cases) was also defined by a large, 15 kb genomic deletion. WGS analysis reveals the existence of multiple transmission chains within the same population/setting. Our results help validate the utility of WGS as a powerful tool for identifying genomic changes and adaptation of M. tuberculosis.

Vulnerability of homeless people in Tehran, Iran, to HIV, tuberculosis and viral hepatitis

BACKGROUND

Homeless people are at risk of contracting communicable infectious diseases, as they indulge in risky behaviours and lifestyle. This study was conducted to determine the prevalence of the aforementioned infections and related risk behaviours among homeless people in Tehran.

METHODS

In this study a convenience sample of 593 homeless individuals was studied. The ELISA method was used for the detection of HIV, HCV and HBV. Clinical symptoms, sputum cultures, acid fast bacilli smears, and chest X-rays were used to identify active pulmonary tuberculosis, and the Interferon Gamma Release Assay (IGRA) test was used to identify latent tuberculosis.

RESULTS

The prevalence of HIV, HBV, HCV and latent tuberculosis was 3.4%, 2.6%, 23.3% and 46.7%, respectively. Active pulmonary tuberculosis was found in 7 persons (1.2%). Injection drug use was an independent risk factor for HIV, HCV and HBV infections. Older people had a higher proportion of Mycobacterium tuberculosis infection (OR: 2.6, 95%CI: 1.9, 3.7) and HCV positivity (OR: 1.7, 95% CI: 1.1, 2.5).

CONCLUSION

Our findings highlighted that much more attention needs to be paid to the health of homeless people.

Tuberculosis among the homeless, United States, 1994-2010

OBJECTIVES

1) To describe homeless persons diagnosed with tuberculosis (TB) during the period 1994-2010, and 2) to estimate a TB incidence rate among homeless persons in the United States.

METHODS

TB cases reported to the National Tuberculosis Surveillance System were analyzed by origin of birth. Incidence rates were calculated using the US Department of Housing and Urban Development homeless population estimates. Analysis of genotyping results identified clustering as a marker for transmission among homeless TB patients.

RESULTS

Of 270,948 reported TB cases, 16,527 (6%) were homeless. The TB incidence rate among homeless persons ranged from 36 to 47 cases per 100,000 population in 2006-2010. Homeless TB patients had over twice the odds of not completing treatment and of belonging to a genotype cluster. US- and foreign-born homeless TB patients had respectively 8 and 12 times the odds of substance abuse.

CONCLUSIONS

Compared to the general population, homeless persons had an approximately 10-fold increase in TB incidence, were less likely to complete treatment and more likely to abuse substances. Public health outreach should target homeless populations to reduce the excess burden of TB in this population.

A first assessment of Mycobacterium tuberculosis genetic diversity and drug-resistance patterns in twelve Caribbean territories

With the exception of some French-speaking islands, data on tuberculosis (TB) in the Caribbean are scarce. In this study, we report a first assessment of genetic diversity of a convenience sample of Mycobacterium tuberculosis strains received from twelve Caribbean territories by spoligotyping and describe their drug-resistance patterns. Of the 480 isolates, 40 (8.3%) isolates showed resistance to at least one anti-TB drug. The proportion of drug-resistant strains was significantly higher in The Bahamas (21.4%; P = 0.02), and Guyana (27.5%; P < 0.0001), while it was significantly lower in Jamaica (2.4%; P = 0.03) than in other countries of the present study. Regarding genetic diversity, 104 distinct spoligotype patterns were observed: 49 corresponded to clustered strains (2 to 93 strains per cluster), while 55 remained unclustered among which 16 patterns were not reported previously. Combining the study results with regional data retrieved from the international SITVIT2 database underlined a connection between frequency of certain M. tuberculosis phylogenetic lineages and the language spoken, suggesting historical (colonial) and ongoing links (trade, tourism, and migratory flows) with European countries with which they shared a common past.

Latent and active tuberculosis: evaluation of injecting drug users

Background

There is a high risk of tuberculosis (TB) infection among injecting drug users (IDUs).

Objectives

This study aimed to determine the frequency of latent and active TB infection among IDUs.

Materials and Methods

In a cross-sectional study between 2008 and 2009, IDUs referred to the methadone maintenance treatment (MMT) centers in Hamedan-Iran, undergone tuberculin skin test (PPD; purified protein derivative) were recruited. The participants with positive results for PPD test (> 5 mm and > 10 mm in HIV positive and negative cases), undergone other complementary procedures such as chest-X-ray and sputum smear test.

Results

Overall, 268 IDUs between 18 and 70 (mean: 34.5 [8.2]) years were included in the study. PPD test had positive findings in 49 cases (18.3%). There was no significant difference of PPD positivity between HIV positive and negative participants (17.7% vs. 18.5%). An active TB was found among IDUs.

Conclusions

The high prevalence of latent and active TB among IDUs indicates the need for TB screening tests among this population.

Active pulmonary tuberculosis and latent tuberculosis infection among homeless people in Seoul, South Korea: a cross-sectional study

Background

The aim of this study was to determine the prevalence rate of latent TB infection (LTBI) and active TB among homeless in Seoul metropolitan city, South Korea, and to compare the TB burden among homeless people with that of a control group.

Methods

The homeless participants were recruited from five sites between October 30, 2009 and April 12, 2010. LTBI was diagnosed through the QuantiFERON(R) TB Gold In-Tube(QFT-GIT) assay and a tuberculin skin test(TST) and, and active PTB was diagnosed based on chest radiography.

Results

Among 313 participants, the prevalence of LTBI was 75.9% (95% CI, 71.1-80.8%) and 79.8% (95% CI, 74.9-84.7%) based on a QFT-GIT assay and the TST, respectively, and that of active PTB was 5.8% (95% CI, 3.2-8.3%). The prevalence of LTBI among homeless participants was about five times higher than controls. Also, the age-specific prevalence rate ratio of active PTB was as high as 24.86.

Conclusions

The prevalence rate of LTBI as well as active PTB among homeless people was much higher than that of the general population in South Korea. Thus, adequate strategies to reduce the TB burden among homeless people are needed.

Open source electronic health records and chronic disease management

OBJECTIVE

To study and report on the use of open source electronic health records (EHR) to assist with chronic care management within safety net medical settings, such as community health centers (CHC).

METHODS AND MATERIALS

The study was conducted by NORC at the University of Chicago from April to September 2010. The NORC team undertook a comprehensive environmental scan, including a literature review, a dozen key informant interviews using a semistructured protocol, and a series of site visits to CHC that currently use an open source EHR.

RESULTS

Two of the sites chosen by NORC were actively using an open source EHR to assist in the redesign of their care delivery system to support more effective chronic disease management. This included incorporating the chronic care model into an CHC and using the EHR to help facilitate its elements, such as care teams for patients, in addition to maintaining health records on indigent populations, such as tuberculosis status on homeless patients.

DISCUSSION

The ability to modify the open-source EHR to adapt to the CHC environment and leverage the ecosystem of providers and users to assist in this process provided significant advantages in chronic care management. Improvements in diabetes management, controlled hypertension and increases in tuberculosis vaccinations were assisted through the use of these open source systems.

CONCLUSIONS

The flexibility and adaptability of open source EHR demonstrated its utility and viability in the provision of necessary and needed chronic disease care among populations served by CHC.

Counting the homeless: a previously incalculable tuberculosis risk and its social determinants

Tuberculosis (TB) surveillance among the homeless is not supported by the political will necessary for TB elimination. We merged the first stakeholder-accepted enumeration of homeless persons with existing surveillance data to assess TB risk among the homeless in Houston, Texas. The average incidence per 100,000 was 411 among homeless and 9.5 among housed persons. The homeless were more likely than the housed to be US-born, clustered, and in a larger-sized cluster. Multivariate analysis revealed that TB rates among the homeless were driven not by comorbidities but by social determinants. Homeless patients were hospitalized more days than the housed and required more follow-up time. Reporting of TB rates for populations with known health disparities could help reframe TB prevention and better target limited funds.

Prevalence of pulmonary tuberculosis among expatriates subjected to medical visa screening in Abu Dhabi, United Arab Emirates

Introduction: All applicants for work and/or residence in Abu Dhabi are screened for tuberculosis at the time of issuing or renewing their residence visa. The purpose of this study is to assess the prevalence of TB among visa applicants and the likelihood of testing positive among different subgroups.

Methods: Data from the electronic visa screening system was used for a total of 948,504 applicants screened for residence in Abu Dhabi from January to December 2010.

Results: The screening identified 4577 suspected cases of pulmonary tuberculosis (PTB); 1558 people with chest X-ray findings suggestive of prior PTB; 235 smear-positives; and 132 culture-positive cases. The prevalence of active PTB was 39/100,000, with new applicants significantly more likely to test positive compared with renewals (OR: 2.05, 95% CI: 1.5–2.7, P < .001). People coming from African countries had the highest prevalence of TB compared with people from other regions (OR: 21.25, 95% CI: 6.72–67.17, P < .001).

Conclusion: The number of active PTB cases among applicants for visa screening is still of a real concern. Without a rigorous screening system, the disease can spread to the community and hit other people. Certain subgroups were more likely to have the disease; this could provide the scientific foundation for future amendments in the screening requirements.

Addressing tobacco use in homeless populations: recommendations of an expert panel

A diverse group of panelists met for one day on October 21, 2009, in Washington, DC, for the purpose of addressing the high tobacco use prevalence rates in homeless populations; identifying appropriate policy, cessation practices and models for implementation in this population; and providing targeted recommendations for researchers, homeless service providers, tobacco control advocates, and policy makers. The panel was convened by Break Free Alliance, one of six national networks funded by the Centers for Disease Control and Prevention, Office on Smoking and Health. The panelists worked through a process of problem identification, generation of responses, analysis and prioritization, development of recommendations, and arrival of final decisions reached by consensus. The resulting recommendations for addressing tobacco use in homeless populations focused on tobacco non-use policy implementation, cessation programming, and expansion of partnerships and collaborations between tobacco control advocates and social service providers. The panel also identified unanswered research questions that can serve to develop a framework for future initiatives to reduce tobacco use among homeless persons. The expert panel model serves as one approach for engaging nontraditional partners and building consensus among leaders from a variety of sectors to address tobacco use in special populations.

Controversies and unresolved issues in tuberculosis prevention and control: a low-burden-country perspective

Despite declining incidence in most high-income countries, tuberculosis shows no signs of disappearing in the near future. Although surveillance data from most Western European countries show relatively stable declines in the rate of tuberculosis over the past several decades, some have reported either an increasing rate or a decelerating pace of reduction in recent years. The burden of disease now disproportionately affects high-risk groups such as migrants, homeless persons, and prisoners. In view of the concentration of cases in urban areas and high-risk deprived groups, interventions that may not be efficient when applied to the general population may be highly cost effective when targeted at high-risk groups. In this article, we examine some controversial elements of tuberculosis prevention and control in low-burden countries and recommend issues for further research. In particular, we assess current evidence on the duration of protection by BCG vaccine, the screening of migrants and hard-to-reach groups, and the use of preventive therapy for contacts of cases of infectious multidrug-resistant tuberculosis. This analysis is presented from the perspective of low-tuberculosis-burden, high-income countries attempting to eliminate tuberculosis.

Abandono ou descontinuidade do tratamento da tuberculose em Rio Branco, Acre

Esta pesquisa investiga os fatores que estão relacionados à descontinuidade do tratamento da tuberculose em Rio Branco-Acre e foi realizada com uma contribuição da etnografia para uma apreensão da realidade a ser estudada. Foi desenvolvida em duas etapas de mapeamento: na primeira, procedeu-se à busca de informações na base de dados do SINAN (Sistema de Notificação de Agravos Nacional) e na Coordenação Municipal do Programa de Tuberculose, a segunda etapa procurou registrar fatos a partir da observação do atendimento numa unidade de saúde que presta assistência aos portadores de tuberculose em tratamento, e entrevistas com eles, assim como de profissionais que prestavam assistência. Na análise das observações, coletas de narrativas e entrevistas, observou-se que os profissionais dos serviços de saúde caracterizam algumas pessoas como propícias a descontinuarem o tratamento e não consideram os diferentes modos de vida na abordagem de seus pacientes, dificultando, assim, a formação do vínculo e favorecendo a descontinuidade ou o abandono. Identificou-se também que as pessoas que faziam o tratamento da tuberculose tinham várias formas de lidar com as limitações que foram geradas pela doença, como a restrição para o trabalho, entre outras, e as pessoas que o descontinuaram levavam em consideração seu sistema de crenças e valores, bem como a própria percepção de saúde/doença, devido a estarem se sentindo curados quando o interromperam.

Tuberculosis in sheltered homeless population of Rome: an integrated model of recruitment for risk management

The authors show the results of an integrated model for risk management of tuberculosis in a sample of sheltered homeless in Rome. Tuberculin skin test (TST) was used for evaluating the prevalence of latent infection (LTBI). In TST positives, expectorate was collected and chest X-ray was achieved. Multiple logistic regression analysis was performed to investigate determinants of infection. Out of 288 recruited subjects, 259 returned for the TST reading; 45.56% were positive and referred to a specialized center; 70 accessed the health facility and completed the clinical pathway. The risk factors associated to LTBI were male gender (OR = 3.72), age over 60 years (OR = 3.59), immigrant status (OR = 3.73), and obesity (OR = 2.19). This approach, based on an integrated social network, guarantees high adherence to screening (89.93%), allowing patients testing positive for latent tuberculosis infection to be diagnosed and rapidly referred to a specialized center.

Tuberculosis among drug users and homeless persons: impact of voluntary X-ray investigation on active case finding

BACKGROUND

Illicit drug use and homelessness are major contributors to the incidence of tuberculosis (TB) among inhabitants of major cities.

OBJECTIVE

The primary objective of this study was to establish a sustainable low-threshold chest X-ray screening programme for pulmonary TB among illicit drug users and homeless persons and to integrate this into the existing public health programme for active case finding. A secondary objective was to estimate the coverage of the programme, assess other risk factors and determine TB rates and treatment outcome in these two groups.

METHODS

Illicit drug users and homeless persons were asked to voluntarily participate in an X-ray screening programme. The coverage of the intervention, total number and characteristics of cases and the follow-up of treatment were assessed.

RESULTS

A total of 4,529 chest radiographs were made from 3,477 persons, of whom 66% were homeless and 34% were illicit drug users, between May 2002 and April 2007. Coverage for screening once every 2 years ranged between 18 and 26%. Thirty-nine TB cases (14 drug users, 25 homeless persons) were identified, representing 8.7% of the total case load of 448 notified cases of pulmonary TB in Frankfurt during this period. Among the drug users, human immunodeficiency virus coinfection (10/14) seemed to play a key role in the development of TB. The case-finding rate of 861/100,000 radiographs (1,122/100,000 persons) is as high as that in routine contact investigations (1,078/100,000). Among all individuals with TB, 76% completed treatment.

CONCLUSION

A novel targeted TB screening approach with voluntary radiographic examination of illicit drug users and homeless persons can be integrated into the existing public TB prevention programme and provides a high case-finding rate.

Giving TB wheels: Public transportation as a risk factor for tuberculosis transmission

Previous geospatial analysis of the well-defined Houston Tuberculosis Initiative (HTI) database identified an association between the use of city-bus transportation (inclusive of time onboard) and Tuberculosis (TB) incidence in Houston/Harris County census tracts (paper submitted). This paper is an extension of those findings. Contact investigations on school buses have reported a high rate of positive tuberculin skin tests in the persons traveling with the index case and have shown an association with bus ride duration. In Houston, city bus routes are veins connecting even the most diverse of populations within the metropolitan area. Among HTI participants, TB patients who reported weekly bus use were more likely to have demographic and social risk factors associated with poverty, immune suppression and health disparities. An equal proportion of bus riders and non-bus riders were cultured for Mycobacterium tuberculosis (MTB), yet 75% of bus riders were clustered with a mean cluster size of 50.14, indicating recent transmission, compared to 56% of non-bus riders (OR = 2.4, p < 0.001) with a mean cluster size of 28.9 (p < 0.01). Individual bus routes, including one route servicing the local hospitals, were found to be risk factors for endemic MTB clustered strains and the routes themselves geographically connect the census tracts previously identified as having endemic TB.

Tuberculosis and homelessness in Montreal: a retrospective cohort study

Background

Montreal is Canada's second-largest city, where mean annual tuberculosis (TB) incidence from 1996 to 2007 was 8.9/100,000. The objectives of this study were to describe the epidemiology of TB among homeless persons in Montreal and assess patterns of transmission and sharing of key locations.

Methods

We reviewed demographic, clinical, and microbiologic data for all active TB cases reported in Montreal from 1996 to 2007 and identified persons who were homeless in the year prior to TB diagnosis. We genotyped all available Mycobacterium tuberculosis isolates by IS6110 restriction fragment length polymorphism (IS6110-RFLP) and spoligotyping, and used a geographic information system to identify potential locations for transmission between persons with matching isolates.

Results

There were 20 cases of TB in homeless persons, out of 1823 total reported from 1996-2007. 17/20 were Canadian-born, including 5 Aboriginals. Homeless persons were more likely than non-homeless persons to have pulmonary TB (20/20), smear-positive disease (17/20, odds ratio (OR) = 5.7, 95% confidence interval (CI): 1.7-20), HIV co-infection (12/20, OR = 14, 95%CI: 4.8-40), and a history of substance use. The median duration from symptom onset to diagnosis was 61 days for homeless persons vs. 28 days for non-homeless persons (P = 0.022). Eleven homeless persons with TB belonged to genotype-defined clusters (OR = 5.4, 95%CI: 2.2-13), and ten potential locations for transmission were identified, including health care facilities, homeless shelters/drop-in centres, and an Aboriginal community centre.

Conclusions

TB cases among homeless persons in Montreal raise concerns about delayed diagnosis and ongoing local transmission.

Tuberculosis outbreak investigations in the United States, 2002-2008

To understand circumstances of tuberculosis transmission that strain public health resources, we systematically reviewed Centers for Disease Control and Prevention (CDC) staff reports of US outbreaks in which CDC participated during 2002–2008 that involved >3 culture-confirmed tuberculosis cases linked by genotype and epidemiology. Twenty-seven outbreaks, representing 398 patients, were reviewed. Twenty-four of the 27 outbreaks involved primarily US-born patients; substance abuse was another predominant feature of outbreaks. Prolonged infectiousness because of provider- and patient-related factors was common. In 17 outbreaks, a drug house was a notable contributing factor. The most frequently documented intervention to control the outbreak was prioritizing contacts according to risk for infection and disease progression to ensure that the highest risk contacts were completely evaluated. US-born persons with reported substance abuse most strongly characterized the tuberculosis outbreaks in this review. Substance abuse remains one of the greatest challenges to controlling tuberculosis transmission in the United States.

A population-based assessment of the health of homeless families in New York City, 2001-2003

OBJECTIVES

We compared estimated population-based health outcomes for New York City (NYC) homeless families with NYC residents overall and in low-income neighborhoods.

METHODS

We matched a NYC family shelter user registry to mortality, tuberculosis, HIV/AIDS, and blood lead test registries maintained by the NYC Department of Health and Mental Hygiene (2001-2003).

RESULTS

Overall adult age-adjusted death rates were similar among the 3 populations. HIV/AIDS and substance-use deaths were 3 and 5 times higher for homeless adults than for the general population; only substance-use deaths were higher than for low-income adults. Children who experienced homelessness appeared to be at an elevated risk of mortality (41.3 vs 22.5 per 100,000; P < .05). Seven in 10 adult and child deaths occurred outside shelter. Adult HIV/AIDS diagnosis rates were more than twice citywide rates but comparable with low-income rates, whereas tuberculosis rates were 3 times higher than in both populations. Homeless children had lower blood lead testing rates and a higher proportion of lead levels over 10 micrograms per deciliter than did both comparison populations.

CONCLUSIONS

Morbidity and mortality levels were comparable between homeless and low-income adults; homeless children's slightly higher risk on some measures possibly reflects the impact of poverty and poor-quality, unstable housing.

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.

The New Homelessness Revisited

The 'new homelessness' has drawn sustained attention from scholars over the past three decades. Definitional inconsistencies and data limitations rendered early work during this period largely speculative in nature. Thanks to conceptual, theoretical, and methodological progress, however, the research literature now provides a fuller understanding of homelessness. Contributions by sociologists and other social scientists since the mid-1990s differentiate among types of homelessness, provide credible demographic estimates, and show how being homeless affects a person's life chances and coping strategies. Agreement also exists about the main macro- and micro-level causes of homelessness. Active lines of inquiry examine public, media, and governmental responses to the problem as well as homeless people's efforts to mobilize on their own behalf. Despite the obstacles faced when studying a stigmatized population marked by high turnover and weak anchors to place, recent investigations have significantly influenced homelessness policy. A greater emphasis on prevention should further strengthen the research-policy nexus.

Housing insecurity and lack of public assistance are risk factors for tuberculin skin test conversion among persons who use illicit drugs in New York City

BACKGROUND

Persons who use illicit drugs are at increased risk of new tuberculosis (TB) infection. We conducted a prospective cohort study to assess rates and risk factors for tuberculin skin test (TST) conversion among persons with a history of illicit drug use, who were enrolled in a methadone program and had a negative baseline 2-step TST (eligible participants).

METHODS

TST and standardized interviews were administered to 401 eligible participants from 1995 through 1999, every 6 months for a 2-year follow-up time. Analyses were conducted in 2006.

RESULTS

A total of 1,447 repeat TSTs were performed during 843 person-years of follow-up (median: 2.0 years). The TST conversion rate was 3.7 per 100 person-years. In multivariate analysis, participants who converted were more likely to report ever having been homeless (HR, 2.4; 95% CI, 1.2-5.0) or ever having lived in a homeless shelter (HR, 2.4; 95% CI, 1.2-4.9) at the baseline interview, and less likely to have reported receiving public assistance since the last study visit (RR, 0.15; 95% CI, 0.07-0.32).

CONCLUSIONS

This is the first study utilizing 2-step TST at baseline to measure the incidence of TST conversion among persons who use illicit drugs. Controlling for homelessness, persons with a lack of current public assistance was identified as a risk factor for TST conversion. These individuals may most benefit from annual tuberculin skin testing.

The association between alcohol use, alcohol use disorders and tuberculosis (TB). A systematic review

BACKGROUND

In 2004, tuberculosis (TB) was responsible for 2.5% of global mortality (among men 3.1%; among women 1.8%) and 2.2% of global burden of disease (men 2.7%; women 1.7%). The present work portrays accumulated evidence on the association between alcohol consumption and TB with the aim to clarify the nature of the relationship.

METHODS

A systematic review of existing scientific data on the association between alcohol consumption and TB, and on studies relevant for clarification of causality was undertaken.

RESULTS

There is a strong association between heavy alcohol use/alcohol use disorders (AUD) and TB. A meta-analysis on the risk of TB for these factors yielded a pooled relative risk of 2.94 (95% CI: 1.89-4.59). Numerous studies show pathogenic impact of alcohol on the immune system causing susceptibility to TB among heavy drinkers. In addition, there are potential social pathways linking AUD and TB. Heavy alcohol use strongly influences both the incidence and the outcome of the disease and was found to be linked to altered pharmacokinetics of medicines used in treatment of TB, social marginalization and drift, higher rate of re-infection, higher rate of treatment defaults and development of drug-resistant forms of TB. Based on the available data, about 10% of the TB cases globally were estimated to be attributable to alcohol.

CONCLUSION

The epidemiological and other evidence presented indicates that heavy alcohol use/AUD constitute a risk factor for incidence and re-infection of TB. Consequences for prevention and clinical interventions are discussed.