Canine Hookworms

Hookworms (Ancylostoma caninum, Ancylostoma braziliense, Uncinaria stenocephala) are one of the classical groups internal parasites of puppies, the others being roundworms, tapeworms, and coccidia.  Hookworm infection has several features that are of interest to the caretakers of dogs.

  • Hookworms (particularly Ancylostoma caninum) suck blood.
  • Hookworms can be transmitted to unborn pups.
  • Hookworms can infect humans.

The adult hookworm lives in the small intestine of its host where it hangs on to the intestinal wall using its 6 sharp teeth.

Hookworm larvae can be swallowed when the dog licks contaminated dirt from his feet. The egg hatches in the environment and develops from a first stage larva (the hatchling) to a second stage larva and finally a third stage larva, which is ready to infect a new host.

Hookworm infection is frequently lethal to young puppies. Infected puppies are commonly pale, weak, and have long-standing deficiencies. They may or may not have diarrhea.

Treatment involves deworming with one of several products: mebendazole (Telmintic®), milbemycin (Interceptor®), moxidectin (Coraxis®), fenbendazole (Panacur®), pyrantel pamoate (Nemex®, Drontal®, or Strongid T®) and others. The Companion Animal Parasite Council has recommended automatically deworming puppies for hookworms beginning at age two weeks in areas where hookworms are common.

Hookworms is a zoonotic disease—can infect humans.  Hookworm infection in the skin is intensely itchy but usually treatable. Local restrictions on bringing dogs to beaches and the strict clean-up laws reflect concern for hookworm (and roundworm) infection in people.

Feline Hookworms

There are two species of hookworms in cats: Ancylostoma tubaeforme and Ancylostoma braziliense.  There are a few differences between cats and dogs with hookworms:

Kittens cannot be infected before birth nor can they be infected by nursing. Cats are generally infected by larvae invading the skin or by eating an infected prey animal.

Both dogs and cats can be infected by eating a vertebrate host such as a rodent.  A scuttling bug can be a tempting toy for a cat in particular and if eaten, the cockroach can transmit hookworm larvae it is carrying. The cockroach can also infect dogs.

The Companion Animal Parasite Control Council recommends deworming kittens beginning at age three weeks with pyrantel pamoate.  There are numerous products approved for the treatment of feline hookworm infection: ivermectin, milbemycin oxime, emodepside (active ingredient in Profender®), selamectin, and moxidectin.

Hookworms are significant parasites in both dogs and cats and constitute a human hazard as well. Very young pets are at highest risk for blood so it is important to deworm regularly. If you have further questions or concerns about hookworms, remember your veterinarian is always there to see that you get the answers you need.