Spread of HIV-1 to children in Cambodia

Abstract

Beginning November 1, 1995, children under 5 years of age, who were admitted to Kantha Bopha Hospitals and who were suspected tuberculosis cases, were screened for human immunodeficiency virus 1 (HIV-1) using enzyme-linked immunosorbent assay (ELISA). By January 31, 1997, 9026 children, 83% of the under 5-year-olds admitted, had been tested; 290 (3.2%) were positive. Serum samples from 205 children of the 236 seropositive children under the age of 18 months were tested for p24 antigen; 51 (25%) were positive. Mothers of 173 of the seropositive children were tested for antibodies to HIV; 170 were positive, which suggests that the main mode of acquisition of HIV-1 in the children was vertical transmission. If HIV-1 infection occurred only in the 54 seropositive children older than 18 months and in the 51 children younger than 18 months with detectable p24 antigen, the calculated prevalence of HIV-1 in children under 5 years old who were suspected of having tuberculosis when admitted to Kantha Bopha Children's Hospitals would be 1.2%. If the 17% not included in the test were all negative, the prevalence would be 1%. This is an underestimate because some of the children not tested could be positive and because some of the children tested had indeterminate HIV status. HIV testing was extended to all children admitted to the hospital; 715 were younger than 5 years of age, 596 of whom were suspected of having tuberculosis, and 119 of whom were not. The seroprevalences for the 2 subgroups were 3.2% and 0.8%, respectively. None of the 369 older children was seropositive. In 1996, the World Health Organization estimated a seroprevalence of 1.97% in adults 15-49 years old in Cambodia, the highest among Asian countries. The blood bank at Kantha Bopha found 211 (6.6%) HIV-1 seropositives among 3197 donors in 1995 and 211 (7.5%) among 2834 donors in 1996. Similar figures were seen at the National Transfusion Centre in Phnom Penh. A 1996 survey in Cambodia found an HIV-1 seroprevalence of 40.9% in prostitutes and 1.7% in pregnant women. The vertical transmission of HIV-1 to children may increase because the virus appears to have been introduced recently to Cambodia; this is indicated by lack of seropositivity in children older than 5 years of age.