Subcontracting Bill & Melinda Gates: Design of the STH pilot study: Evaluate cfDNA as a biomarker of STH infection

The gastrointestinal tract of a child living in a low income country is highly likely to be parasitized with at least one of three main Soil- transmitted helminths (STH; Ascaris /umbricoides (roundworms), Trichuris trichiura (whipworms), Ancylostoma duodenale and Necator americanus (hookworms). Ascaris a·nd Trichuris are the most prevalent infecting 800-1100 million people and 600-800 million people respectively. The disease burden attributable to STHs can be controlled with a combination of mass drug administration, and improved hygiene and sanitation in at-risk populations. It is essential to measure the impact of intervention strategies through epidemiological mapping, however there is currently a lack of easy to implement diagnostic methods that are able to detect low levels of infection.

The overall aim of this pilot study is to validate the uitility of cfDNA in screening STH infections in humans. The study design entails a proof-of-principle study for Ascaris suum in a pig model that enables controlling the level of infection followed by a trial in human subjects from a STH endemic area.