Does regular deworming of schoolchildren in areas endemic for intestinal worms improve their physical health and school performance? Commentary on an Evidence Summary

Abstract

The findings of this Cochrane systematic review may at first glance appear counter intuitive and invite controversy. However, when one focuses on the patterns that emerge, it becomes clear that the findings are consistent with biological expectations.1Sudarsanam T.D. Tharyan P. Does regular deworming of schoolchildren in areas endemic for intestinal worms improve their physical health and school performance? Summary of the evidence and implications for public health programmes.CEGH. 2013; 1: 25-29Google Scholar 1.Deworming was beneficial when administered to children who were screened and found to have worm infestation as compared to no treatment.2.Studies carried out in high endemic areas are expected to be more likely to show benefit following deworming than other regions; however, this was not observed in sub-group analyses in the review of trials conducted in high, moderate or low endemic areas.3.More recent studies tended to show less benefits compared to earlier studies carried out in the same region. It is well known that bulk of the health-related effects due to worm infestations depend on the worm loads. Indeed, when one screens children for worm infestation in an endemic area, one is separating those with higher worm loads from the rest. Similarly, there are likely to be more children with higher worm loads in high endemic areas. It seems very likely that if there has been a secular trend towards declining worm load in countries from where the data for this review emerged, then more recent studies will tend to show little or no benefit following mass deworming as compared to earlier studies. This systematic review must compel health-planners in endemic areas to review their future course of action based on the current levels of infection and the anticipated benefits that may follow attempts to get rid of intestinal worms by deworming programmes.