Routinely Available Cotrimoxazole Prophylaxis and Occurrence of Respiratory and Diarrhoeal Morbidity in Infants Born to HIV-infected Mothers in South Africa

Objectives: To examine the influence of cotrimoxazole (CTM) prophylaxis on incidence of lower respiratory tract infections (LRTIs) and diarrhoea.

Design: A prospective observational cohort study. Morbidity and feeding data on infants born to HIV-infected mothers were collected routinely at clinic visits at 1 week, 6 weeks and 3 months, and 3-monthly thereafter, with blood drawn for determining HIV status.

Setting: Two hospitals in Durban, South Africa. In one hospital (King Edward VIII Hospital), infants born to HIV infected mothers received CTM prophylaxis and in the other (McCord Hospital) infants did not receive CTM prophylaxis.

Subjects: Infants born to HIV-infected mothers. Outcome measures. Incidence of LRTI and diarrhoea.

Results: In multivariate analysis controlling for breast-feeding status, number of clinic visits and HIV infection status, HIV infected infants with access to CTM prophylaxis had a significantly lower incidence of LRTI (82%) than those without access to prophylaxis. However in HIV-uninfected infants, this was not the case. CTM prophylaxis was associated with a non-significant increased risk for diarrhea in both infected (odds ratio (OR) 1.58, p = 0.45) and uninfected infants (OR 1.52, p = 0.10).

Conclusions: This observational study confirms current thinking that CTM prophylaxis is protective against LRTIs in HIV-infected children. However, because of a possible association between CTM prophylaxis and an increased risk of diarrhoea, HIV status of infants should be determined as early as possible in order to prevent unnecessary exposure of uninfected infants to CTM prophylaxis, while further studies to quantify both beneficial and adverse effects of CTM prophylaxis are undertaken.