The epidemiology of HIV-1 infection in urban areas, roadside settlements and rural villages in Mwanza Region, Tanzania
Barongo, L.R.; Borgdorff, M.W.; Mosha, F.F.; Nicoll, A.; Grosskurth, H.; Senkoro, K.P.; Newell, J.N.; Changalucha, J.; Klokke, A.H.; Killewo, J.Z.
Aids 6(12): 1521-1528
1992
ISSN/ISBN: 0269-9370 PMID: 1492935 DOI: 10.1097/00002030-199212000-00016Document Number: 305120
Between August 1990 and February 1991, health workers took blood samples from, and trained interviewers spoke to, 5145 15-to-54-year-old adults living in either an urban area (1554), in a rural village (2434), or in a roadside settlement (1157) in the Mwanza Region of Tanzania to determine the prevalence of HIV-1 infection and its most significant risk factors. The prevalence rate of HIV-1 infection was highest in urban areas, lower in roadside settlements, and lowest in rural areas (11.8%, 7.3%, and 2.5%, respectively), suggesting that HIV-1 had spread along main roads. Yet, there were as many people infected with HIV-1 in rural areas of the Mwanza Region as there were in Mwanza town. Women were 1.2 (rural) to 1.7 (urban) times more likely to be infected with HIV-1 than were men, indicating greater efficiency of HIV-1 transmission from men to women than from women to men. HIV-1 infection peaked in the 15-to-34-year-old group in women and in the 25-to-44-year-old group in men. Separated, divorced, or widowed men and women were at increased risk of being HIV-1 infected, even when controlled for numerous factors (odds ratio (OR) = 3.4 and 1.6, respectively). This may have been an indication of multiple partners, since the question concerning multiple partners was vague. Other important risk factors for women and men were syphilis antibodies (OR = 1.7 and 1.85), history of genital discharge or chancroid (OR = 2, 1.6 and 2.7, 1.6), travel to Mwanza town (OR = 2.1 and 1.7), and receiving injections during the previous 12 months (OR = 1.5 and 1.9). There was no link between male circumcision and HIV-1 infection. In fact, there seemed to be a moderate protective effect (OR = 0.8). This effect may be even more likely since urban men, who were at greatest risk of HIV-1 infection (8.7% vs. 5.4% ), had the highest rate of circumcision (61% vs. 29% and 17%, respectively).