Cost-Effective to Scale Up Prevention of Common Parasitic Worm Diseases

Findings from a new study that looked at the cost-effectiveness of expanding treatment guidelines for parasitic worm diseases support a substantial scaling up of treatment with community-wide coverage in areas in which these diseases are endemic.

Led by researchers at Stanford University School of Medicine, the study used a cost-effective and prevalence model that simulated an integrated approach to implementing preventive chemotherapy programs against both both schistosomiasis and soil-transmitted helminthiasis.

Under current guidelines by the World Health Organization (WHO), annual preventive treatment is recommended in communities in which schistosomiasis is prevalent in 50% or more of the population and soil-transmitted helminthiasis is prevalent in 20% or more of the population.

Using the model, the researchers found that annual prevention against schistosomiasis was highly cost-effective for school-aged children when the prevalence in the community was 5% and for community-wide when the prevalence was 15%. For soil-transmitted helminthiasis, annual prevention was highly cost-effective for school-age children and community-wide when the prevalence rates were 20% and 60%, respectively.

When using an integrated prophylactic approach to treat both parasitic worm diseases in areas in which both were endemic, the prevalence thresholds were even lower.

Jason Andrews, MD, Assistant Professor of Medicine, and lead author of the study, said in a press release that the findings indicate that increasing treatment for schistosomiasis by six times and soil-transmitted helminth infections by two times the current estimated needs in sub-Saharan Africa makes economic sense.

“These worms cause an array of health effects from anemia, malnutrition and growth stunting to infertility, cancer of the urinary tract and liver cirrhosis,” Dr Andrews said. “Mass drug administration of the scale we’ve proposed could prevent these problems. Our analysis indicates that this would not only be effect but also cost-effective investment when compared alongside other health interventions.”

References

Lo NC, Lai YS, Karagiannis-Voules DA, et al. Assessment of global guidelines for preventive chemotherapy against schistosomiasis and soil-transmitted helminthiasis: a cost-effectiveness modeling study [published online ahead of print June 7, 2016]. Lancet Infect Dis. doi: 10.1016/S1473-3099(16)30073-1.