This article describes and assesses the epidemiology of AIDS and HIV infection in Costa Rica. Costa Rica was placed third among the seven Central American countries - both in terms of cumulative AIDS incidence and the cumulative number of cases. The high male:female ratios of people reported with AIDS (11:1) and HIV infections (14:1) and the high proportion of AIDS cases (72%) transmitted by male-to-male sexual contact give grounds for considering Costa Rica to be a Pattern I country - one where the disease is transmitted primarily among homosexual/bisexual males. Increasing numbers of heterosexual and perinatal cases, high rates of HIV infection among pregnant women, and existing patterns of bisexuality are consistent with a possible shift toward a Pattern I/II epidemic. -from English summary
