Mother-to-child transmission of HIV-2 infection from 1986 to 2007 in the ANRS French Perinatal Cohort EPF-CO1.

Background. Management of pregnant women with human immunodeficiency virus (HIV) type 2 infection remains unclear because of its low prevalence and important differences from HIV-1. Methods. Pregnant women monoinfected with HIV-2 or HIV-1 and their infants enrolled in the prospective, national, multicenter French Perinatal Cohort between 1986 and 2007. Results. Overall, 2.6% (223/8660) of mothers were infected with HIV-2, and they accounted for 3.1% (367/11841) of the total births. Most were born in sub-Saharan Africa. A higher proportion of HIV-2-infected mothers than HIV-1-infected mothers had no symptoms, had received no antiretroviral threrapy at conception (85.9% vs 66.7%), and had received no antiretroviral therapy during pregnancy (42.8% vs 19.9%), particularly highly active antiretroviral therapy (HAART) (79.7% vs 46.1%), and they had higher CD4 cell counts near delivery (median, 574 vs 452 cells/mm(3); P < .01). If antiretroviral therapy was used, it was started at a later gestational age for HIV-2-infected mothers (median, 28 vs 25 weeks; P < .01). HIV-2-infected mothers were more likely to deliver vaginally (67.9% vs 49.3%) and to breastfeed (3.6% vs 0.6%; P < .01), and their infants less frequently received postexposure prophylaxis. In the period 2000-2007, the proportion with viral load <100 copies/mL at delivery was 90.5% of HIV-2-infected mothers, compared with 76.2% of HIV-1-infected mothers (P = .1). There were 2 cases of transmission: 1 case in 1993 occurred following maternal primary infection, and the other case occurred postnatally in 2002 and involved a mother with severe immune deficiency. The mother-to-child transmission rate for HIV-2 was 0.6% (95% confidence interval, 0.07%-2.2%). Conclusions. Care for HIV-2-infected pregnant women rests on expert opinion. The mother-to-child transmission residual rate (0.07%-2.2%) argues for systematic treatment: protease inhibitor-based HAART for women requiring antiretroviral therapy or for primary infection and simplified prevention of mother-to-child transmission in other instances.