The ETVAX vaccine against enterotoxigenic Escherichia coli, or ETEC — one of the main causes of diarrhea in young children and of “traveler’s diarrhea” — has finally delivered a truly serious clinical result. In a large randomized, double-blind study in Gambia, 4,936 children aged 6 to 18 months were followed for up to two years. This is one of the largest tests of an ETEC vaccine candidate in children.
No serious vaccine-related side effects were identified, and the immune response was robust. The primary endpoint was not formally met: in infections caused exclusively by ETEC, the reduction in moderate-to-severe diarrhea was 26.6%. But secondary and exploratory results were markedly stronger. When cases with co-infections were included, efficacy reached 48.2%, and among children who received the first dose before 9 months of age, it was 67.8%. In addition, the number of moderate and severe episodes of diarrhea from any cause fell by 21.4%.
ETEC is one of the key causes of childhood diarrhea in low-income countries and the most common cause of so-called traveler’s diarrhea. According to the study authors, this infection is associated with about 75 million diarrhea episodes and up to 42,000 child deaths per year. For young children, the risk of dehydration and malnutrition is especially high.
If these data are confirmed in further studies, global pediatrics would gain a tool that could reduce the number of severe diarrhea episodes, ease the burden on clinics, and possibly cut unnecessary antibiotic use.
