TY - JOUR
T1 - Effect of BCG on the risk of leprosy in an endemic area
T2 - A case control study
AU - Muliyil, J.
AU - Nelson, K. E.
AU - Diamond, E. L.
PY - 1991
Y1 - 1991
N2 - The effect of BCG on the risk of leprosy was measured using a case-control design in an area endemic for the disease. In this study, 397 newly diagnosed cases and 669 controls matched for age, sex and locality were selected from a defined population. Information on exposure to BCG, contact with another case of leprosy, and relevant socio-economic variables were obtained from the subjects. Having infectious (multibacillary) and noninfectious (paucibacillary) contacts in the household increased the risk of disease 11.7 times (p < 0.001) and 2.7 times (p < 0.001), respectively. Overall, the protection offered by BCG was not significant (odds ratio = 0.8; p = 0.17). However, BCG appeared to increase the risk for indeterminate leprosy (adjusted odds ratio = 2.7; p = 0.09) while protecting against borderline disease (adjusted odds ratio = 0.39; p = 0.03). It is possible that BCG causes a shift in the overall cell-mediated immune response, thus increasing the risk for milder and transient forms of leprosy while protecting against more serious forms. These findings may have important implications for the design and interpretation of vaccine trials. Namely, trials should be designed to measure the protective efficacy of vaccines against the more serious forms of leprosy, which have the greatest public health significance.
AB - The effect of BCG on the risk of leprosy was measured using a case-control design in an area endemic for the disease. In this study, 397 newly diagnosed cases and 669 controls matched for age, sex and locality were selected from a defined population. Information on exposure to BCG, contact with another case of leprosy, and relevant socio-economic variables were obtained from the subjects. Having infectious (multibacillary) and noninfectious (paucibacillary) contacts in the household increased the risk of disease 11.7 times (p < 0.001) and 2.7 times (p < 0.001), respectively. Overall, the protection offered by BCG was not significant (odds ratio = 0.8; p = 0.17). However, BCG appeared to increase the risk for indeterminate leprosy (adjusted odds ratio = 2.7; p = 0.09) while protecting against borderline disease (adjusted odds ratio = 0.39; p = 0.03). It is possible that BCG causes a shift in the overall cell-mediated immune response, thus increasing the risk for milder and transient forms of leprosy while protecting against more serious forms. These findings may have important implications for the design and interpretation of vaccine trials. Namely, trials should be designed to measure the protective efficacy of vaccines against the more serious forms of leprosy, which have the greatest public health significance.
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M3 - Article
C2 - 2071979
AN - SCOPUS:0025837901
SN - 0148-916X
VL - 59
SP - 229
EP - 236
JO - International Journal of Leprosy
JF - International Journal of Leprosy
IS - 2
ER -