By Maggie Brown
Posted: January 27, 2012
Diarrhea, abdominal pain, malaise, anemia, and delayed child development: these are the debilitating effects of one group of diseases, the soil-transmitted helminths (worms). As indicated by the name, these diseases are transmitted via contaminated soil; as such, good sanitation has a key role in prevention. However, because sanitation systems vary greatly, their impact is difficult to study. Now, a PLoS Medicine systematic review and meta-analysis (a reanalysis of data from already published studies), by Ziegelbauer and coauthors, quantifies the benefits of sanitation: for all three of the STHs, when sanitation was both available and regularly used, the odds of getting a worm disease was cut in half.
One billion of the world’s people experience a diminished ability to work, learn, and thrive as a result of infection by these parasites – roundworm, whipworm, and hookworm. The resulting losses in quality of life and productivity can trap people in a cycle of poverty and stigma and diminish their ability to care for themselves and their families.
Currently, the primary approach to the problem is repeat drug treatment. As important as drugs are, though, they also have limitations: reinfection in endemic areas; possible reduced efficacy and development of resistance; and supply, delivery, and compliance problems. Drug administration can go only so far, and currently many programmatic goals are not being met. For the STHs, many authors argue that integrated control is the only hope for lasting improvement (see Further Reading).