Rotavirus vaccine efficacy in African and Asian countries Reply
No Thumbnail Available
Date
2010-12
Journal Title
Journal ISSN
Volume Title
Publisher
The Lancet
Abstract
The pentavalent rotavirus vaccine offers an opportunity to affect child health positively, particularly in regions of the world with high diarrhoea morbidity and mortality. Although our study focused on the prevention of severe gastroenteritis, we agree with Stephen Obaro that the vaccine might be effective against less common outcomes, including mortality. In fact, such an effect has been shown in postmarketing studies, most notably in Mexico, where introduction of a rotavirus vaccine into the national immunisation programme correlated with a significant reduction in all-cause diarrhoea mortality.1
Our studies used a passive “catchment” design to identify cases of rotavirus gastroenteritis, and, as Obaro suggests, health-care use did interfere with optimum case ascertainment. Indeed, in the Mali site, gastroenteritis episodes were managed largely by traditional healers during the first year of the study, resulting in very few cases identified and a limited capacity to contribute to vaccine efficacy calculations. When this problem was identified and addressed at the end of the first rotavirus season, the number of cases identified increased substantially.