Protective efficacy of BCG against leprosy in São Paulo.

The case-control study reported here evaluated the protective effect of BCG vaccine against leprosy in São Paulo, Brazil. Seventy-eight patients under age 16 who had been diagnosed as having leprosy (cases) and 385 healthy individuals (controls) were selected and matched by sex, age, place of residence, and type of exposure to leprosy (intradomiciliary or extradomiciliary). The cases were drawn from an active patient registry and from a group of new leprosy cases treated at 50 health centers in the cities of Bauru and Ribeirão Preto in the state of São Paulo. In order to estimate the protective effect of BCG, the prevalences of BCG scars in cases and controls were compared. The presence of one or more scars was associated with an estimated protective efficacy of 90% (95% confidence interval: 78% to 96%). Stratified analysis by age group, sex, socioeconomic level, and clinical form of the disease revealed no significant differences in the protection provided by the vaccine. However, it seems clear that more data will be needed in order to accurately assess the true relevance of BCG for leprosy control programs.

[The protective efficacy of BCG against leprosy in São Paulo, Brazil]. / Eficacia protectora del BCG contra la lepra en São Paulo, Brasil.

The protection against leprosy conferred by BCG vaccination was evaluated in a case-control study. Selected for the study were 97 patients under 16 years of age who had been diagnosed with leprosy (cases) and 385 healthy persons (controls), who were matched according to sex, age, place of residence, and type of contact (intra- or extradomicilliary). The cases were selected from a register of active cases as well as a series of new leprosy patients treated in 50 centers in the city of São Paulo, Brasil. To estimate the protective effect of BCG, the prevalences of BCG scars among cases and controls were compared. The presence of one or more scars was associated with a protective efficacy of 90% (95% confidence interval: 78%-96%). Stratified analysis by age group, sex, socioeconomic level, and clinical form of leprosy did not reveal any important differences in the protection conferred by the vaccine. The significance of these findings and the appropriateness of using BCG in leprosy control programs is discussed.

Spatial patterns of leprosy in an urban area of central Brazil.

Reported is the spatial variation of leprosy in an urban area of Brazil and its correlation with socioeconomic indicators. From November 1991 to October 1992 a total of 752 newly diagnosed leprosy patients who were attending all outpatient clinics in Goiânia city, central Brazil, were identified. A database o leprosy cases was set up linking patients' addresses to 64 urban districts. Leprosy cases were detected in 86% of the districts and three risk strata were identified. The highest-risk area for leprosy was in the outskirts of the city and detection rates increased on moving from more developed to poorer areas. The risk of detecting leprosy cases was 5.3-fold greater (95% CI: 3.8-7.4) in the outskirts of the town than in the central zone. Discussed are the methodological issues related to leprosy case ascertainment, completeness and reliability of information, and the interpretation of the spatial distribution of leprosy per unit area. Highlighted also are the lack of leprosy control activities in primary health care units and the usefulness of geographical analysis in planning health services.

Agreement between histopathological results in clinically diagnosed cases of indeterminate leprosy in São Paulo, Brazil.

Histopathological slides from skin biopsies of fifty-seven self-reporting patients diagnosed as indeterminate leprosy by the Leprosy Control Programme in São Paulo, were sent to three independent histopathologists. Agreement between the reports were based on the following diagnosis: "indeterminate leprosy", "suggestive leprosy" or "no leprosy". A great variation was observed in the interpretation of the histopathological examination. The three pathologists reported "indeterminate leprosy" respectively in 7.0%, 54.4% and 84.2%, of the cases studied. A kappa index of agreement between any two pathologists ranged from 0.08 to 0.32, showing poor agreement between observers. Agreement improved by pooling together the reports "suggestive leprosy" and "indeterminate leprosy". The three pathologists agreed in the results of 24 biopsies of the 27 classified as leprosy by any one of the three observers. Eight cases were considered as "no leprosy" by all pathologists. Higher agreement indices were obtained for positive and negative proportionate concordance between any two examiners. The implications of the variation in the diagnosis of indeterminate leprosy and early leprosy are discussed in the context of public health and case-management.

Association between leprosy and hepatitis B infection. A survey in Goiânia, central Brazil.

This investigation presents the results of hepatitis B virus screening among leprosy patients conducted in central Brazil as a preliminary information for a HBV vaccination programme. The main objectives were to assess the seroprevalence of HBV serum markers among lepromatous patients and to analyse institutionalization as risk factor for HBV infection in this population. Two groups of lepromatous patients were studied, 83 outpatients and 171 institutionalized ones. Screening for HBV serum markers included the detection of HBsAg, anti-HBc by radioimmune assay (RIA). The prevalence of carrier state (HBsAg) was 4.8% and 8.8% among outpatients and institutionalized, respectively, (p > 0.05). Seroprevalence of exposure (all markers) was statistically significant different between outpatients (16.9%) and institutionalized ones (50.3%). Institutionalized patients had an almost four fold risk of HBV infection when compared to the outpatients, and the highest risks were among patients with more than 21 years of residence in the colony, after adjusting for age and sex.

Protective effect of intradermal BCG against leprosy; a case-control study in central Brazil.

A case-control study was undertaken to evaluate the protective efficacy of intradermal BCG against leprosy in a high-endemic area of leprosy in central Brazil. Sixty-two cases and 186 controls were included in the study. Cases were all newly diagnosed leprosy patients under 16 years of age attending an outpatient health service, and all of them were schoolchildren. Three controls under 16 years old, frequency matched by sex and age group, were selected from schools geographically located in the area from which the cases came. The presence of BCG was negatively associated with leprosy, indicating a 5.3 risk of leprosy for those nonvaccinated and protective efficacy of 81%. Paucibacillary patients were more likely to have a BCG scar than multibacillary patients.