Prevalence and factors associated with latent tuberculosis infection in an indigenous population in the Brazilian Amazon

Abstract

Introduction:Recent studies have shown a high incidence and prevalence of latent tuberculosis infection (LTBI) in indigenous populations around the World. We aimed to estimate the prevalence and annual risk of infection (ARI) as well as to identify factors associated with LTBI in an indigenous population from the Brazilian Amazon. Methods: We conducted a cross-sectional study in 2011. We performed tuberculin skin tests (TSTs), smears and cultures of sputum samples, and chest radiographs for individuals who reported cough for two or more weeks. Associations between LTBI (TST ≥5mm) and socio-demographic, clinical, and epidemiological characteristics were investigated using Poisson regression with robust variance. Prevalence ratio (PR) was used as the measure of association. Results: We examined 263 individuals. The prevalence of LTBI was 40.3%, and the ARI was 2.4%. Age ≥15 years [PR=5.5; 95% confi dence interval (CI): 3.5-8.6], contact with tuberculosis (TB) patients (PR=3.8; 95% CI: 1.2-11.9), previous TB history (PR=1.4; 95% CI: 1.2-1.7), and presence of Bacillus Calmette-Guérin (BCG) scar (PR=1.9, 95% CI: 1.2-2.9) were associated with LTBI.Conclusions: Although some adults may have been infected years prior, the high prevalence of infection and its strong association with age ≥15 years, history of TB, and recent contact with TB patients suggest that the TB transmission risk is high in the study area.

Antineutrophil cytoplasmic antibodies in Chinese patients with tuberculosis

“…Compared with previous studies 1,3,4,10,11,[15][16][17] , this study recruited patients with many types of tuberculosis, including spinal tuberculosis, peritoneal tuberculosis, and tuberculous meningitis. Based on the findings of this study, patients who were ANCA-positive (especially for MPO or PR3) were more likely to have other ANCA-related disorders.…”

Acesso aos serviços de saúde para o diagnóstico e tratamento da tuberculose entre povos indígenas do estado de Rondônia, Amazônia Brasileira, entre 2009 e 2011: um estudo transversal*

“…The Vilhena DSEI, which also covers part of Mato Grosso state, concentrates its actions in four municipalities and is responsible for the health care of 7000 indigenous people. 18 We chose Rondônia because of the sizeable occurrence of TB cases in the region between 1997 and 2006,5,9,17,19 as well as the perspective of the local DSEIs expressing the capacity of the Indigenous Health subsystem to detect TB cases among the population that lives in indigenous lands both within and outside of Rondônia state.…”

“…Interest in tuberculosis among indigenous peoples has been increasing since 1990. 1,2 In Brazil there are reports of active tuberculosis incidence rates three times higher than the national averages, 2,3 prevalence of latent infection in excess of 40% in the Northern region, [4][5][6] considerable concentration of cases in border regions, 7,8 a drug resistance emergency 8,9 and patterns of recent transmission in 63.5% of cases in Mato Grosso do Sul state (1999)(2000)(2001). 10 The level of these indicators is a result of socio-economic disadvantages, discrimination, prejudice and indigenous people having difficulty in accessing health services.…”

Latent Tuberculosis Infection in Patients with Multiple Sclerosis

“…Therefore, tuberculosis infection remains an important public health problem in Brazil. The most vulnerable population to TB are homeless persons, prisoners, health professionals, and indigenous populations (Malacarne J, et al 2016).…”