His major research interests have included onchocerciasis and loiasis and, to a lesser extent, ascariasis and trichuriasis. Within neglected tropical diseases, Dr. Pion focuses on topics such as the evaluation of the relationship between onchocerciasis and epilepsy, optimization of drug regimens for lymphatic filariasis elimination in Central Africa, assessment of the possible development of ivermectin resistance in Onchocerca volvulus, and prevention of Loa loa related adverse reactions occurring during mass drug administration with ivermectin in onchocerciasis endemic areas. Dr. Pion has authored and co-authored over 75 scientific publications on the topics.