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Soil Transmitted Helminthiasis

Infestation with parasitic worms of the helminth class. Source: DECS/BIREME


© PAHO/WHO

Helminths, transmitted by contact with soil and known as STH or intestinal parasites, are the most common infections worldwide and affect the poorest and most vulnerable populations. The causative agents are Ascaris lumbricoides, Trichuris trichiura, and hookworms. In the Americas, soil-transmitted helminths are present throughout the Region. It is estimated that one out of every three people is infected with geohelminths. Close to 46 million children between the ages of 1 and 14 are at risk of infection by these parasites [approximately 13 million pre-school age children (1 to 4 years) and 33.3 million school age children (5 to 14 years)] due to lack of basic sanitation and access to clean water. Infection is most common in women and children. Lack of access to water and sanitation causes the persistence of these infections. Mass deworming once or twice a year in communities and countries with high prevalence, practicing personal hygiene measures, and increasing access to water and sanitation are interventions to reduce the burden of disease. The PAHO Member States committed themselves to reducing the prevalence of STH by 2015 to less than 20% in school-age children living in high risk areas of infection.

General information about this disease

Strategic Partners

[ Collaborating Centers Website ]

Regional Office for the Americas of the World Health Organization
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