Maternal age, infant age, feeding options, single/multiple pregnancy, type of twin sets and mother-to-child transmission of HIV.

BACKGROUND: Some risk factors for mother-to-child transmission (MTCT) of HIV have been identified. To further reduce MTCT, other risk factors were evaluated. MATERIALS AND METHODS: A retrospective study on early infant diagnosis was conducted. Two-sided chi-square test was used to assess associations with infant HIV status. RESULTS: A total of 15 233 HIV-infected mothers and 15 404 infants were recruited. MTCT rate was 9.34%. Only 3.8% of infants born to mothers on antiretroviral treatment were infected. Under nevirapine, 4.1% of infants were infected. MTCT increased with infant' age at testing. Younger mothers tend to transmit more HIV (P = 0.003). More children were infected in single pregnancies compared with multiple pregnancies, P < 0.001. There were more infections in male-female twins' sets (P = 0.037). CONCLUSIONS: Maternal age, type of pregnancy and twins' sets are new MTCT risk factors. Strategies to further decrease transmission through family planning, pre/post natal consultations and clinical practices are needed.

CCR2 polymorphism and HIV: mutation in both mother and child is associated with higher transmission.

C-C motif chemokine receptor 2 (CCR2) is one of the co-receptors of HIV found on the surface of the target cell and studied as genetic factors known to be associated with HIV infection. This study investigates the influence of mothers' and children's CCR2 polymorphism on HIV acquisition in children. A cross-sectional study was performed in five hospitals in the Northern Region of Cameroon. Blood samples were collected from HIV-infected mothers and their exposed babies. DNA was extracted from the Buffy coat using the QIAamp®DNA mini kit (Qiagen). The DNA extract was subjected to Polymerase Chain Reaction (PCR) followed by Restriction Fragment Length Polymorphism. Hardy-Weinberg Equilibrium (HWE) was verified. A total of 113 HIV-positive mothers, and their 113 children (25 infected and 88 non-infected) under 15 years were enrolled. There was a significant relationship between mothers and children's polymorphisms (P = 0.000). There was a concordance of 57.5% between mothers and children genotypes (Kappa = 0.2, P = 0.001). Mothers carrying the CCR2-64I allele were 1.2 times more likely to have HIV-infected children compared to those without mutation (OR = 1.2, 95% CI: 0.5-3.0). Likewise children carrying the mutated phenotypes were 1.4 times more likely to be HIV-infected compared to those without mutation (OR = 1.4, 95% CI: 0.6-3.5). This risk increased to 2.0 (95% CI: 0.5-8.3) for children whose mothers also carried mutation, and decreased to 0.96 (95% CI: 0.2-3.8) for those whose mothers carried the wild type phenotype. In cases of a mutant phenotype in both mother and child, more attention should be paid during follow-up of children born from HIV-positive mother.