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Rotterdam, Netherlands

Dantes R.,San Francisco General Hospital | Metcalfe J.,San Francisco General Hospital | Kim E.,San Francisco General Hospital | Kato-Maeda M.,San Francisco General Hospital | And 4 more authors.

Background: Specific isoniazid (INH) resistance conferring mutations have been shown to impact the likelihood of tuberculosis (TB) transmission. However, their role in the clinical presentation and outcomes of TB has not been evaluated. Methods: We included all cases of culture-confirmed, INH monoresistant tuberculosis reported to the San Francisco Department of Public Health Tuberculosis Control Section from October 1992 through October 2005. For cases with stored culture isolates, we used polymerase chain reaction (PCR) testing and gene sequencing to identify INH resistance-conferring mutations, and compared genotypic and phenotypic characteristics. Results: Among 101 consecutive cases of INH monoresistant TB in San Francisco 19 (19%) had isolates with a katG mutation other than S315T; 38 (38%) had isolates with the katG S315T mutation, 29 (29%) had isolates with a inhA-15;c-t promoter mutation, and 15 (15%) had isolates with other mutations. The katG S315T mutation was independently associated with high-level INH resistance (risk ratio [RR] 1.56, 95% confidence interval [CI] 1.07-2.27), and the inhA-15;c-t promoter mutation was inversely associated with high-level INH resistance (RR 0.43, 95% CI 0.21-0.89). However, specific INH resistance-conferring mutations were not associated with the clinical severity or outcomes of INH monoresistant TB cases. Conclusion: These data suggest that INH resistance-conferring mutations do not impact the clinical presentation of TB. © 2012 Dantes et al. Source

Mohtashemi M.,Mitre Corporation | Mohtashemi M.,Massachusetts Institute of Technology | Kawamura L.M.,Tuberculosis Control Section

The re-emergence of tuberculosis (TB) in the mid-1980s in many parts of the world, including the United States, is often attributed to the emergence and rapid spread of human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS). Although it is well established that TB transmission is particularly amplified in populations with high HIV prevalence, the epidemiology of interaction between TB and HIV is not well understood. This is partly due to the scarcity of HIV-related data, a consequence of the voluntary nature of HIV status reporting and testing, and partly due to current practices of screening high risk populations through separate surveillance programs for HIV and TB. The San Francisco Department of Public Health, TB Control Program, has been conducting active surveillance among the San Francisco highrisk populations since the early 1990s. We present extensive TB surveillance data on HIV and TB infection among the San Francisco homeless to investigate the association between the TB cases and their HIV+ contacts. We applied wavelet coherence and phase analyses to the TB surveillance data from January 1993 through December 2005, to establish and quantify statistical association and synchrony in the highly non-stationary and ostensibly non-periodic waves of TB cases and their HIV+ contacts in San Francisco. When stratified by homelessness, we found that the evolution of TB cases and their HIV+ contacts is highly coherent over time and locked in phase at a specific periodic scale among the San Francisco homeless, but no significant association was observed for the non-homeless. This study confirms the hypothesis that the dynamics of HIV and TB are significantly intertwined and that HIV is likely a key factor in the sustenance of TB transmission among the San Francisco homeless. The findings of this study underscore the importance of contact tracing in detection of HIV+ individuals that may otherwise remain undetected, and thus highlights the ever-increasing need for HIV-related data and an integrative approach to monitoring high-risk populations with respect to HIV and TB transmission. © 2010 Mohtashemi, Kawamura. Source

Van Hest R.,Tuberculosis Control Section | Grant A.,Public Health England | Abubakar I.,Public Health England
Tropical Medicine and International Health

Objectives Resource-limited countries often lack robust routine surveillance systems to accurately assess the burden of human attributes and diseases. In these settings capture-recapture analysis can be an alternative tool to obtain prevalence and incidence rates. Performance of capture-recapture analyses in resource-limited countries has not been systematically reviewed. Methods Systematic review of the performance of capture-recapture analyses in the categories of human attributes, non-infectious and infectious diseases in resource-limited countries, assessing individual study quality criteria and a minimum quality criterion per category, using PRISMA methodology. Results A total of 1671 potentially relevant PubMed citations were screened, resulting in 52 eligible publications: 36% in human attributes, i.e. hidden populations, injuries and mortality; 48% in non-infectious and 15% in infectious disease categories. Twenty-one per cent of selected studies were from low income countries, 40% from lower-middle-income countries and 38% from upper-middle-income countries. Thirteen per cent achieved good individual study quality criteria, 25% were intermediate and 19% were poor. Of the good studies, six were performed on human attributes and one on a non-infectious disease. The proportions of publications meeting the minimum quality criterion per category were 42%, 20% and 37%, respectively. Conclusions Few capture-recapture studies in resource-limited countries achieved good individual quality criteria and a minority met the minimum quality criterion per category. Capture-recapture techniques in these settings should be carefully considered and implemented rigorously and are not a panacea for strengthening of routine surveillance systems. © 2011 Blackwell Publishing Ltd. Source

Bamrah S.,Centers for Disease Control and Prevention | Brostrom R.,Centers for Disease Control and Prevention | Dorina F.,Chuuk State TB Program | Setik L.,Chuuk State TB Program | And 5 more authors.
International Journal of Tuberculosis and Lung Disease

SETTING: Few studies have shown the operational feasibility, safety, tolerability, or outcomes of multi-drug-resistant latent tuberculous infection (MDR LTBI) treatment. After two simultaneous multidrug-resistant tuberculosis (MDR-TB) outbreaks in Chuuk, Federated States of Micronesia, infected contacts were offered a 12-month fluoroquinolone (FQ) based MDR LTBI treatment regimen. DESIGN: Between January 2009 and February 2012, 119 contacts of MDR-TB patients were followed using a prospective observational study design. After MDR-TB disease was excluded, 12 months of daily FQ-based preventive treatment of MDR LTBI was provided by directly observed therapy. RESULTS: Among the 119 infected contacts, 15 refused, while 104 began treatment for MDR LTBI. Of the 104 who initiated treatment, 93 (89%) completed treatment, while 4 contacts discontinued due to adverse effects. None of the 104 contacts who undertook MDR LTBI treatment of any duration developed MDR-TB disease; however, 3 of 15 contacts who refused and 15 unidentified contacts developed MDR-TB disease. CONCLUSION: Providing treatment for MDR LTBI can be accomplished in a resource-limited setting, and contributed to preventing MDR-TB disease. The Chuuk TB program implemented treatment of MDR LTBI with an 89% completion rate. The MDR LTBI regimens were safe and well tolerated, and no TB cases occurred among persons treated for MDR LTBI. © 2014 The Union. Source

Bassili A.,World Health Organization | Grant A.D.,Public Health England | El-Mohgazy E.,National Tuberculosis Control Programme | Galal A.,National Tuberculosis Control Programme | And 6 more authors.
International Journal of Tuberculosis and Lung Disease

SETTING: Most countries endemic and highly endemic for tuberculosis (TB) still do not have reliable TB surveillance systems. Indirect estimation of TB incidence is needed to monitor the performance of the National Tuberculosis Programme (NTP) in the context of the World Health Organization implementation and impact targets for TB control. OBJECTIVE: To estimate the case detection rate (CDR) of all TB cases and sputum smear-positive TB cases in Egypt in 2007. METHODS: Record linkage and three-source capture-recapture analysis of data collected through active prospective longitudinal surveillance within the public and private non-NTP sector in four Egyptian governorates selected by stratifi ed cluster random sampling. RESULTS: For all TB cases, the estimated CDR of NTP surveillance and completeness of case ascertainment after record linkage was respectively 55% (95%CI 46-68) and 62% (95%CI 52-77). For sputum smear-positive TB cases, these proportions were respectively 66% (95%CI 55-75) and 72% (95%CI 60-82). CONCLUSION: This pilot study shows that representative sampling, prospective surveillance in the non-NTP sector, record linkage and capture-recapture analysis can improve CDR estimation. For global, standardised and reliable use, this methodology should be further developed. Until then, all resource-limited countries should strengthen their national surveillance systems in the context of the Stop TB strategy. © 2010 The Union. Source

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