Ancylostoma duodenale (“Old World” hookworm) and Necator americanus (“New World” hookworm)
Hookworm infection is most often acquired by walking barefoot on feces-contaminated soil. Some hookworm infections can occur in the lining of the mouth.The parasite primarily infects and affects adults (>15 years old). Although women of reproductive age are infected at similar rates as men, they are particularly affected by hookworm. Mild infections usually produce no symptoms but are still associated with lower hemoglobin concentration.  Severe infections result in blood loss, anemia, and protein loss.  Malnutrition can develop among those infected with intestinal worms. Children with these infections may also have mental and physical growth impairments. In addition to causing the majority of STH-associated deaths, hookworm caused an estimated 3.2 million disability-adjusted life years (DALY) in 2010. This represents the estimated number of years lost to ill health, disability, or early death caused by hookworm infections. Hookworm is responsible by for the most DALYs, by far, caused by a STH species.  Hookworm infections are preventable and treatable with prescribed medication.
CDC – Hookworm. Cdcgov. 2020.
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