What’s Eating You? Hookworm and Cutaneous Larva Migrans

Hookworm infection represents a major global disease burden, in terms of both morbidity and economic impact, and there has been a resurgence of hookworms in developed nations where these parasites were once thought to be eradicated. Hookworms can infest humans or other mammals as their primary hosts depending on the species. The 2 most common species that seek human hosts-Necator americanus and Ancylostoma duodenale-enter the body through the epidermis, and hookworm infection may manifest as a pruritic and papular inflammatory reaction know as ground itch. Once they penetrate blood vessels, the hookworms localize in the lungs where they produce an eosinophilic pneumonitis, then they are swallowed with sputum and localize in the gastrointestinal tract in their adult form, with resulting symptoms of iron deficiency. Zoonotic hookworms such as Ancylostoma caninum, Ancylostoma braziliense, and Uncinaria stenocephala can infest pets such as dogs and cats but also can erroneously penetrate the skin when a human comes into contact with soil contaminated with larval hookworms. In such instances, the hookworms cannot traverse the basal layer of the epidermis and remain confined to the stratum spinosum, a condition known as cutaneous larva migrans (CLM).