Praziquantel is effective against various helminthic and protozoan infections. Infection causes a helminthic disease called gastrodiscoidiasis. URTIs can also be fungal or helminthic in origin, but these are less common. The main physiological role of T9 cells, while poorly defined, is defense against helminthic infections. "Necator americanus" has been proposed as an alternative to "Trichuris suis" in helminthic therapy. In 2006, a similar cell population was identified in a case of helminthic infection. When it worked, Lawrence became an advocate for helminthic therapy. "T. suis" is also used in helminthic therapy studies. Jasper Lawrence (born 1964) is a British citizen and advocate of helminthic therapy. For more information on this topic, see Helminthic therapy. It causes a helminthic disease called gastrodiscoidiasis.