Assessing the cost-effectiveness of national Kenyan repeat maternal HIV testing guidelines

Abstract

Kenya has aims to achieve the 95-95-95 goals for prevention of mother-to-child HIV transmission (PMTCT) by 2030; yet, each year there are 13,000 new infant HIV infections. Repeat testing in the third trimester and in the postpartum period, when risk of HIV acquisition is high, can help detect and treat incident maternal infections and reduce mother-to-child HIV transmission. Current data on the timing, frequency, and utility of repeat testing are lacking. We assessed the cost-effectiveness of repeat HIV testing during pregnancy and the postpartum period, comparing various repeat testing scenarios to inform more targeted policies on PMTCT programs, and maximize HIV prevention resources in Kenya. We assessed the cost-effectiveness of 5 repeat testing scenarios, varying the number and timing of repeat testing, in averting infant HIV infections. We constructed a separate decision analytic model for each scenario to estimate the number of infant infections averted, the incremental cost-effectiveness ratio in terms of infections averted (ICER-IA), and the total cost to the Kenyan health care system. As a conservative estimate, repeat testing scenarios were considered to be cost-effective if the ICER-IA was less than 3 times Kenya’s gross domestic product (GDP) per capita ($4365 USD in 2016) and highly cost-effective if less than Kenya’s GDP per capita ($1455 USD in 2016). All repeat testing strategies are cost-effective in averting infant infections. Repeat testing at delivery; at 6 weeks postpartum; at both 6 weeks postpartum and 6 months postpartum; and in the third trimester/at delivery, at 6 weeks postpartum, and at 6 months postpartum (complete repeat testing) are all also considered highly-cost-effective. The most cost-effective strategy is conducting complete repeat maternal HIV testing, which averts a 12,023 infant infections with an ICER-IA of $1,189. The second most cost-effective scenario is repeat testing at 6 weeks postpartum and 6 months postpartum, which averts 8,403 infections at the ICER-IA of $1,249. Repeat testing at 6 weeks postpartum averts 5,160 infections at the ICER-IA of $1,426. Among all the repeat testing scenarios, complete retesting averts the most infant infections and is highly cost-effective. Data on implementation of repeat testing guidelines will be useful to measure health and economic impact of scaling up repeat maternal testing in Kenya.