Tuberculosis transmission patterns among Spanish-born and foreign-born populations in the city of Barcelona

AbstractDuring a 2-year period (2003–2004), tuberculosis (TB) transmission in Barcelona and the factors related to transmission among the Spanish- and foreign-born populations were studied by molecular epidemiology. Data were obtained from TB cases and Conventional Contact Tracing registries and genotyping was performed using restriction fragment length polymorphism (RFLP)-IS6110 and MIRU12 as a secondary typing method. Of the 892 TB cases reported, 583 (65.3%) corresponded to Spanish-born and 309 (34.6%) to foreign-born. Six hundred and eighty-seven cases (77%) were confirmed by culture. RFLP typing of 463/687 (67.4%) isolates was performed, revealing 280 (60.5%) unique and 183 (39.5%) shared patterns, which were grouped into 65 clusters. Spanish-born individuals were significantly more clustered than foreign-born individuals (44.6% vs. 28.8%; p 0.016). Clustering in foreign-born individuals was associated with HIV (p 0.051, odds ratio = 3.1, 95% confidence interval 1–10.9) and alcohol abuse (p 0.022), whereas, in the Spanish-born individuals, clustering was associated with age in the range 21–50 years, (p 0.024). Of the total clusters, 36/65 (55.3%) included only Spanish-born patients, whereas 22/65 (33.8%) included individuals from both populations. In mixed clusters, the index case was Spanish-born in 53% and foreign-born in 47%. Among the foreign-born, 2.8% were ill on arrival, 30% developed TB within the first year and 50.3% developed TB within the first 2 years; 58.3% were from South America. In conclusion, half of the foreign-born TB patients developed the disease during the first 2 years after arrival, which, in most cases, was the result of endogenous reactivation. Recent TB transmission among Spanish-born and foreign-born populations, as well as bidirectional transmission between communities, contributed significantly to the burden of TB in Barcelona, suggesting the need to improve Public Health interventions in both populations

New times for migrants' health in Europe

Patterns of migration can change greatly over time, with the size and composition of migrant populations reflecting both, current and historical patterns of migration flows. The recent economic crisis has caused a decrease on migration flows towards the most affected areas, as well as cut offs in health interventions addressed to migrants. The objective of this paper is to review available data about interventions on migrants' health in Europe, and to describe changes in migrant health policies across Europe after the economic crisis, that can have a negative effect in their health status. Although migrants have the right to health care under legal settlements issued by the EU, there is no a standard European approach to offer health care to migrants, since; policies in each EU Member State are developed according to specific migrant experience, political climate, and attitudes towards migration. Migrants use to face greater health problems and major health care access barriers, compared with their counterparts from the EU. Therefore, migrant health policies should focus in protects this vulnerable group, especially during economic hardship, taking into account economic and socio-demographic risk factors. There is an especial need for research in the cost-effectiveness of investing in the health care of the migrant population, demonstrating the benefit of such, even in the health of the European native population, and the need for constant intervention despite of resource constraints

How does tuberculosis relate to HIV positive and HIV negative drug users?

OBJECTIVES—(1) To compare the incidence of active tuberculosis in HIV positive and HIV negative drug users. (2) To describe the main characteristics of the tuberculosis cases.
DESIGN—A prospective study was performed from 1986 to 1996 as part of an ongoing cohort study of HIV infection in Amsterdam drug users.
METHODS—Data from the cohort study, including HIV serostatus and CD4-cell numbers, were completed with data from the tuberculosis registration of the tuberculosis department of the Amsterdam Municipal Health Service. Analyses were carried out with person time and survival methods.
RESULTS—Of 872 participants, 24 persons developed culture confirmed tuberculosis during a total follow up period of 4000 person years (0.60 per 100 py, 95% CI: 0.40, 0.90). Nineteen cases were HIV positive (1.54 per 100 py, 95% CI: 0.86, 2.11) and five HIV negative (0.18 per 100 py, 95% CI: 0.08, 0.43). Multivariately HIV infection (relative risk: 12.9; 95% CI: 3.4, 48.8) and age above 33 years (RR: 6.8; 95% CI: 1.3, 35.0, as compared with age below 27) increased the risk for tuberculosis substantially. Additional findings were: (1) 13 of 22 pulmonary tuberculosis cases (59%) were detected by half yearly radiographic screening of the chest; (2) tuberculosis occurred relatively early in the course of HIV infection at a mean CD4 cell number of 390/µl; (3) an estimated two thirds of the incidence of tuberculosis observed among HIV positive cases was caused by reactivation; (4) all but one patient completed the tuberculosis treatment.
CONCLUSION—HIV infection increases the risk for active tuberculosis in Amsterdam drug users 13-fold. The incidence of tuberculosis in HIV negative drug users is still six times higher than in the overall Amsterdam population. In the absence of contact tracing and screening with tuberculin skin tests, periodic chest radiographic screening contributes substantially to early casefinding of active tuberculosis in Amsterdam drug users.


Keywords: tuberculosis; drug users; epidemiology; HIV infection; longitudinal studie