Option B+ in Malawi: Antiretroviral therapy for prevention of mother-to-child HIV transmission and its effects on preterm birth and female-to-male HIV transmissio

Large number of new and prevalent HIV infections among reproductive-aged women in sub-Saharan Africa makes prevention of mother-to-child HIV transmission (PMTCT) a major public health priority. Option B+ is a simplified approach to PMTCT that recommends universal life-long ART for pregnant and breastfeeding women regardless of HIV disease stage or CD4 count. This approach is expected to help bring an end to new pediatric HIV infections and substantially improve maternal health in settings with high HIV burdens. However, the effect of ART initiation during pregnancy in the Option B+ era on birth outcomes and female-to-male HIV transmission is not well known.;We used maternity-ward data from Bwaila Hospital in Lilongwe, Malawi to estimate the risk of preterm birth among HIV-infected women. The risk of preterm birth was similar in women who had initiated ART at any point prior to delivery compared to those who never initiated ART (adjusted Risk Ratio (aRR) = 0.88; 95% CI: 0.65--1.19). No clear trend between timing of ART and risk of preterm birth was observed. ART initiation at any point before delivery was strongly protective against extremely to very preterm birth (27--32 weeks gestation) (aRR = 0.43; 95% CI: 0.26--0.72).;Using mathematical modeling we estimated the female-to male HIV infections using two PTMTC approaches, Option B and Option B+ in the period 2011--2020. The estimated relative incidence (RI) under Option B+ was 4% lower (median RI = 0.96; 95% CI: 0.94--0.97) in 2015 and was projected to be 7% lower (median RI = 0.93; 95% CI: 0.90--0.95) by 2020 compared to the Option B in which ART uptake values in the period 2011--2020 assumed to be the same for Option B as those assumed for Option B+. When Option B ART uptake values in the period 2011--2020 were assumed to remain at 2011 levels, the estimated RI under Option B+ was 14% lower (median RI = 0.86; 95% CI: 0.84--0.88) in 2015 and was projected to be 21% lower (median RI = 0.79; 95% CI: 0.74--0.83) by 2020.