Using a Health-Rating System to Determine the Effect of Anthelmintics Using L1 C. elegans

Indianapolis, IN

Over 1.5 billion impoverished people world-wide are infected with at least one of three different soil-transmitted helminths (STHs), which are parasitic worms where part of their life cycle is in soil. These are either swallowed (eggs of either whipworm or Ascaris) or skin penetrate (hookworm), and then grow and develop in the body. Of the most affected are women and children. The WHO has approved four drugs for mass drug administration (MDA) to treat these infections and these four anthelmintic drugs together carry out a total of two mechanisms of action. Of these drugs, albendazole is the drug of choice and resistance has already been shown. Caenorhabditis elegans, a free-living nematode usually found dwelling in rotten fruit, has been used in laboratories for drug screening and study of anthelminitics. Hu et al. showed, using a dead/alive scale, that albendazole had no effect in C. elegans. Recently, Weaver et al. showed, using a health-rating system (3-0), that albendazole on L4 C. elegans made the worms sick, compared to controls, even though the worms did not die. Here, we look to further investigate the effect of albendazole (and other classes of anthelmintics) on C. elegans starting with the L1 stage. This study will give a better understanding of the effects of albendazole when exposed at an earlier stage of development and may also give insights into treating the parasites before they are adults. For example, an idea for control is to spray fields with anthelmintics in attempt to prevent the infection in the first place. Specifically, for hookworm, which goes from L1-L3 stages while in the soil, an effective drug that could weaken and kill the parasites before they are able to infect and reproduce could be quite useful in combating infection.