The effect of birth weight and gestational age on BCG-induced immune responses in infants following BCG vaccination

Includes bibliographical references (leaves 102-114).Bacillus Calmette?Gu?rin (BCG), the only currently licensed tuberculosis (TB) vaccine, provides variable efficacy. Despite the use of BCG, TB remains a global health problem. BCG is administered at birth; however, more than 15% of infants are born preterm [PT (90% of these born in developing countries, where the majority of TB cases are found. It is not known how birth weight at the time of vaccination may affect the BCG-induced immune response and subsequent protection against TB. We hypothesised that BCG-vaccinated PT and LBW infants would have a qualitatively and quantitatevely less optimal immune response, compared to term or normal birth weight (NBW) infants