Reduced Poliovirus vaccine neutralising-antibody titres in infants with maternal HIV-exposure

► Both maternally HIV-exposed and infected infants had reduced neutralising-antibodies to polio vaccine. ► The proportion of antibody-titres below protective levels were increased in both maternally HIV-exposed and infected infants. ► Trial of micronutrient fortification in 743 randomised infants had no effect on vaccine antibody titre. ► We report effects of breast-feeding and HCMV infection on reduced antibody titres.