Can chemotherapy alone eliminate the transmission of soil transmitted helminths?

BACKGROUND: Amongst the world's poorest populations, availability of anthelmintic treatments for the control of soil transmitted helminths (STH) by mass or targeted chemotherapy has increased dramatically in recent years. However, the design of community based treatment programmes to achieve the greatest impact on transmission is still open to debate. Questions include: who should be treated, how often should they be treated, how long should treatment be continued for?

METHODS: Simulation and analysis of a dynamic transmission model and novel data analyses suggest refinements of the World Health Organization guidelines for the community based treatment of STH.

RESULTS: This analysis shows that treatment levels and frequency must be much higher, and the breadth of coverage across age classes broader than is typically the current practice, if transmission is to be interrupted by mass chemotherapy alone.

CONCLUSIONS: When planning interventions to reduce transmission, rather than purely to reduce morbidity, current school-based interventions are unlikely to be enough to achieve the desired results.