Helminth Infection Research

Hookworms (Necator sp.) are gastrointestinal nematodes that infect almost 1 billion people in developing countries. The main clinical symptom of human hookworm infections is iron-deficiency anemia, a direct consequence of intestinal blood loss resulting from the parasite’s feeding behavior. Hookworms survive by ingesting host blood, breaking down red blood cells, and digesting hemoglobin via a proteolytic cascade in their digestive tracts that involves enzymes such as the aspartic protease-1 (Na-APR-1) and glutathione S-transferase-1 (Na-GST-1). Recent data obtained from a proof-of-concept clinical trial using a controlled human infection model confirmed that the Na-GST-1 recombinant hookworm vaccine candidate conferred over 90% protection. The CVD is very interested in advancing this Na-GST-1 hookworm vaccine as a stand-alone product or possibly in combination with a malaria vaccine to generate a much-needed anti-anemia vaccine that would comprehensively counter these co-endemic diseases affecting millions of people in Sub-Saharan Africa. In parallel, the CVD team has also integrated the GST-1 antigen into a novel mRNA platform, preparing for future pan-helminthic vaccines.

Roundworms (Ascaris spp.) are large intestinal parasites that live and mature in the human gut. Infection occurs when individuals ingest eggs from contaminated soil or food. In endemic regions, Ascaris is a leading cause of malnutrition and intestinal obstruction, affecting an estimated 500 million people worldwide, the majority of whom are children. To identify new intervention or control strategies, including vaccine targets and other approaches to reduce helminth-induced morbidity, we are investigating the long-term health consequences for children living in poverty-endemic areas with studies to understand how the parasite triggers inflammation, shapes immune cell polarization, and alters cytokine responses.

Whipworms (Trichuris spp.) are a major global health burden, affecting an estimated 500 million people, primarily children in low-income regions. Infections contribute to chronic dysentery, anemia, stunted growth and significant disability. We are pursuing the development of a Trichuris vaccine, with the potential to integrate it into a novel pan-helminthic vaccine strategy. For instance, we are advancing projects in Latin America to identify whipworm seroprevalence using sensitive markers and improving surveillance methods beyond stool diagnostics. This enables stronger baseline epidemiology and impact assessment to support future vaccine development.

Schistosomiasis has one of the highest disease burden NTDs, especially in Africa, where more than 90% of infections occur. It is a parasitic disease spread by freshwater snails, and after malaria, it is the deadliest parasitic disease plaguing more than 250 million people worldwide. For over a decade, the CVD has been advancing the Sm-TSP-2 schistosomiasis vaccine, targeting the worm’s outer syncytial surface accessible to the host immune system. Several clinical trials have been completed in non-endemic and endemic populations, and similar to our other helminth vaccine projects, we continue to improve our development efforts by assessing and combining different vaccine technologies.