HIV-1 infection as a risk factor for leprosy; a case-control study in Tanzania.
A case-control study was carried out in Tanzania to determine the relative risk of those with HIV-1 infection for getting leprosy. Cases were 93 consecutively diagnosed patients with leprosy aged 15-54 years from the Mwanza Region. Controls were a representative population sample of 4161 people drawn from a stratified cluster sample from urban areas, roadside settlements, and rural villages. HIV-1 infection was determined by enzyme-linked immunosorbent assay (ELISA); Western blot was used when the ELISA result was indeterminate. The HIV-1 prevalence in leprosy cases was 10% in rural (7 of 72) and in roadside and urban areas (2 of 21); in controls these prevalences were 3.4% and 9.9%, respectively. The relative risk of HIV-1 infection for the development of leprosy was estimated to be 2.2 [95% confidence interval (CI) = 1.0-4.7; p = 0.07]. HIV-1 infection was significantly associated with multibacillary (MB) leprosy (odds ratio 4.6; CI = 1.3-13.2) but not with paucibacillary leprosy (odds ratio 1.4; 95% CI = 0.4-3.8). The population etiological fraction for the development of MB leprosy attributable to HIV-1 infection in this population is estimated to be 13% (95% CI = 4%-23%). We conclude that HIV-1 is a risk factor for the development of MB leprosy. The impact of the HIV-1 epidemic on the incidence of leprosy so far has been limited since HIV-1 occurs mainly in urban areas and leprosy in rural areas.
Borgdorff
M W
MW
National Institute for Medical Research, Mwanza, Tanzania.
van den Broek
J
J
Chum
H J
HJ
Klokke
A H
AH
Graf
P
P
Barongo
L R
LR
Newell
J N
JN
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D016022:Case-Control Studies; D005260:Female; D015483:HIV Antibodies / Q000097:blood; D015658:HIV Infections / Q000150:complications* / Q000453:epidemiology; D015497:HIV-1 / Q000276:immunology; D006801:Humans; D007918:Leprosy / Q000150:complications* / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D015995:Prevalence; D012307:Risk Factors; D012424:Rural Population; D017678:Sex Distribution; D012867:Skin / Q000382:microbiology; D013636:Tanzania / Q000453:epidemiology; D014505:Urban Population
D015483:HIV Antibodies