What is the primary mode of transmission for hookworm infection?

The primary mode of transmission for hookworm infection is indeed contact with contaminated soil. Hookworms, specifically species like Ancylostoma duodenale and Necator americanus, are transmitted when their larvae penetrate the skin of a host, typically through bare feet that come into contact with contaminated soil. This larval stage of the hookworm resides in soil that has been contaminated with human feces, where adult worms lay eggs that hatch into larvae.

Individuals exposed to contaminated environments, particularly in areas lacking proper sanitation, are at a higher risk of infection. The larvae can survive in warm, moist soil, and they readily enter the body through the skin, making soil contact the central route of transmission for this parasitic infection.

Other transmission methods described in the choices, like ingestion of contaminated food or insect bites, do not apply to hookworms, as they do not have a fecal-oral route of transmission or an insect vector involved in their lifecycle. Similarly, direct person-to-person contact is not a recognized mode of transmission for hookworms, reinforcing the importance of preventive measures focused on minimizing contact with contaminated soil.