Epidemiological and sociological aspects of HIV-infection in developing countries.

The epidemiologic and social aspects of AIDS are different in developed and developing countries. In Africa, where there are several tens of thousands of cases, the ratio of female to male cases is 1:1. The highest incidence in men is at age 37.4 and in women 30 years. In Haiti the female to male ratio is 1:1.8. In Rwanda and Zambia the incidence is higher among educated people. In most of Africa AIDS is predominantly urban. Also, in Africa the time between diagnosis and death is shorter. Seroprevalence rates in Africa and the Caribbean are between .5 and 18% for the population at large. In Zaire seroprevalence peaks between ages 16-20 and at under 1 year. Both in the US and in Africa the epidemic appears to have begun around 1980. In West Africa a related virus, HIV-2, has been identified. Progression rates from seropositivity to AIDS or AIDS-related complex in Africa are similar to those in the US. However, in Africa, and recently in Haiti, transmission has been heterosexual. In Africa female prostitutes have the highest incidence of HIV seropositivity, and there is much female to male transmission via this route. Genital ulcers, especially chancroid, increase the risk of AIDS, and condom use may protect women from infection. The 2nd most important route of AIDS transmission in Africa and Haiti is blood transfusion. Blood transfusion are common in treatment of children with anemia from malaria and with sickle cell anemia, and many children have been infected via this route in Africa. Medical injections, scarification and circumcision also account for HIV transmission. Perinatal transmission from seropositive mothers is also common in Africa. Among patrilineal African societies premarital or extramarital sex is rare among girls, but young men and husbands of nursing mothers often visit prostitutes. In the cities there are varying degrees of promiscuity. In couples where the husband is seropositive, he usually has a history of sex with prostitutes, but in couples where the wife is seropositive, she usually has a history of blood transfusion.