Background:  The Uganda Ministry of Health prevention of mother-to-child transmission (PMTCT) guidelines recommend exclusive breastfeeding and abrupt weaning between 3 to 6 months of age to reduce the risk of HIV transmission. These guidelines, however, must be balanced against the risks associated with early replacement feeding among HIV-exposed infants, especially serious gastroenteritis events and mortality.

Methods:  We evaluated rates of gastroenteritis and mortality pre- and post-breastfeeding cessation in infants enrolled in an ongoing immunoglobulin/antiretroviral trial for PMTCT. In the trial, mothers are counseled on exclusive breastfeeding for 3 to 6 months and to then stop all breastfeeding by 6 months. Data on infant feeding practices, illnesses, hospitalizations, and deaths are collected at each visit. We assessed hazard rates of first serious gastroenteritis (hospitalizations and dysentery per National Institutes of Health Division of AIDS toxicity tables) by month of age as well as mortality events among HIV-negative exposed infants.

Results:  We followed 579 HIV^– infants, of whom 65 (11.2%) had serious gastroenteritis. The median age of complete breastfeeding cessation was at 3.0 months (interquartile range 2 to 6 months); and median age of serious gastroenteritis among these children was 6 months. Rates of serious gastroenteritis seen within 3 months pre- and 3 months post-weaning were 1.7% (95%CI  0.9 to 3.0) and 3.9% (95%CI 2.6 to 5.8), respectively. Serious gastroenteritis rates among HIV^– infants rose from 3 to 5 months and peaked between 6 and 7 months of age (see the table). There were 15 infant deaths (5 due to gastroenteritis) among the HIV^– children post breastfeeding cessation, while no infant deaths occurred in the pre-weaning period.

Conclusions:  In the HIVIGLOB trial, breastfeeding cessation was associated with increased risk of serious gastroenteritis among HIV^– infants. Rates of serious gastroenteritis doubled from the breastfeeding period until the 3-month period post-breastfeeding cessation; and infant deaths rose sharply within 3 months after breastfeeding cessation. Increased counseling efforts are urgently needed to support HIV-infected mothers to safely wean their infants. Likewise, current WHO and Ministry of Health guidelines for early weaning of HIV-exposed infants need careful reassessment as to risks and benefits including risk of infant mortality.