Objectives: To determine the vertical transmission rate of HIV-2 and clinical findings associated with vertically transmitted HIV-2 infection.
Design: A prospective study of HIV-2 transmission in children of HIV-2-seropositive mothers, and a comparison of clinical findings between children of seropositive and seronegative mothers.
Setting: Recruitment of women delivering at the national hospital in Bissau, Guinea-Bissau. Follow-up by home visits.
Subjects and methods: Eighty-six newborns of 82 HIV-2-seropositive mothers and a control group of 102 newborns of HIV-seronegative mothers were followed-up clinically and by HIV serology until the children reached the age of 20 months.
Results: Of the 86 children of seropositive mothers, 51 had a complete follow-up, 22 died and 13 were lost due to change of residence. Of the 102 children of seronegative mothers, 63 had a complete follow-up, 13 died and 26 were lost due to change of residence. None of 51 children of seropositive mothers had serological evidence of HIV-2 infection at the end of the follow-up period. There was no significant difference in the frequency of clinical symptoms between the children in the study group and the children in the control group. The mortality during the first year of life was not significantly different between the children of seropositive and seronegative mothers (13 out of 80 and 11 out of 94, respectively, P > 0.05, excluding children lost to follow-up). Only three of the dead children of seropositive mothers and one of the dead children of seronegative mothers had any symptoms that might be related to HIV-2 infection (diarrhoea > 1 month).
Conclusion: Vertical transmission of HIV-2 appears to be rare.
PIP: Between May 1987 and December 1988 in Guinea-Bissau, health workers followed 86 HIV-2 seropositive mothers and their infants delivered at the National Hospital Simao-Mendes in Bissau for 20 months to learn the HIV-2 vertical transmission rate and to compare their clinical findings with those of 102 infants of HIV-2 seronegative women. The ELISA and Western Blot analysis used antigen-purified virions of the SBL-6669 strain of HIV-2 grown on U937:2 cells. During the enrollment period, hospital workers tested 3246 women; tests confirmed that 211 (6.5%) and 3 (0.1%) were HIV-2 seropositive, respectively. 1 HIV-2 seronegative mother seroconverted during the study, but none of the infants of HIV-2 seronegative mothers seroconverted. Infant mortality of cases did not differ significantly from that of controls (16.2% vs. 11.7%). After 1 year of age, however, children of HIV-2 seropositive mothers were significantly more likely to die than the controls (15% vs. 3%; p .05). When the researchers added the children lost to follow up, there no longer was a significant difference in mortality after 1 year (23.9% vs. 24.1%). Just 3 of the deceased infants of the HIV-2 seropositive mothers and 1 of the deceased infants of seronegative mothers suffered from symptoms from symptoms that may have been related to HIV-2 infection. 1 of these deceased infants was HIV-2 seropositive at 12 months. These symptoms included prolonged fever, vomiting, diarrhea, and respiratory symptoms. Children in the study group did not experience more frequent clinical symptoms of HIV-2 infection than did the controls during the 3rd and 4th home visits. At the last visit (i.e., 4th visit; when the children were older than 17 months), none of the children of the HIV-2 seropositive mothers tested positive for HIV- 2. Vertical transmission of HIV-2 infection may be rare.