How Much Paediatric HIV Infection Could Be Prevented by Antenatal HIV Testing?

Objective To estimate the reduction in the number of children infected with HIV that might be achieved by extending the provision of voluntary antenatal HIV testing. This effect would be mediated by increased numbers of women infected with HIV who receive an intervention to reduce the risk of vertical transmission (for example, zidovudine or caesarean section delivery), who use an alternative to breast feeding, or whose pregnancy is terminated. Setting London, United Kingdom. Methods Relevant data were derived from neonatal seroprevalence studies, obstetric and paediatric reporting schemes, and review of external information. Sensitivity analyses were performed for certain parameters. Results Of 106 000 births annually in London, an estimated 169 are to women infected with HIV whose infection is not currently recognised before pregnancy. An estimated 28–33 children born to these women will be infected. Precise prediction of the number of paediatric HIV infections that could be prevented is difficult because of uncertainty in certain factors, particularly the uptake of antenatal testing and the efficacy and acceptability of interventions to reduce prenatal or perinatal transmission. If a testing programme detected 70% of infected women, none of whom opted for a termination but all of whom exclusively bottle fed and received an intervention which halved the risk of transmission, about 12–16 (42–46%) paediatric HIV infections would be prevented annually. Conclusions — The estimated cost of preventing each paediatric infection is high, but this should be seen in the context of the lifetime health and social care costs for a child infected with HIV. The feasibility of selective testing should be considered when formulating policies on antenatal HIV testing. Programmes that are introduced should be audited to obtain better estimates of costs and benefits.