By sequencing of HIV-1 pol/env genes and phylogenetic analysis, we performed a molecular epidemiologic study in a representative subset (n = 200) of the 508 HIV-1-seropositive individuals followed up at the center for HIV/AIDS care and treatment of Guangzhou Hospital of Infectious Diseases.
We examined the genetic makeup of 221 HIV-1 strains from Chilean persons living with HIV/AIDS by HMA and DNA sequencing of the env gene: 143 cases were infected by sexual contact with an already-infected partner, 76 were infected by mother-to-child transmission, and 2 were transfusion related.