Hookworms are one of the most common parasites plaguing the companion animal world. They use their hooklike mouths to latch onto an animal’s intestines, where they feast on tissue fluids and blood.

Right now, U.S. veterinarians rely on three types of drugs to kill the hookworms, but the parasites appear to becoming resistant to all of them. Dog hookworms can also infect humans. Hookworms are one ...