Whipworm Infection in Cats: Causes, Symptoms & Effective Treatment

Our pets can be hosts to a number of intestinal parasites, including roundworms, hookworms, tapeworms, and whipworms. These parasites can affect the overall health and wellbeing of our companion animals. Whipworm infections can be especially challenging. They are harder to diagnose and treat and their eggs are much more hearty than other intestinal parasites.

Types of Whipworms

There are two species of whipworms that can infect cats: Trichuris serrata is found in North America and Trichuris campanula is found in Europe. Whipworms are species-specific and Trichuris vulpis, does not survive in cats.

Causes and Transmission Mechanisms

You will not see adult whipworms in the feces of an infected cat. To make this diagnosis, the microscopic whipworm eggs are identified in a specially treated stool sample from the infected cat, usually through fecal floatation. This is why your veterinarian recommends you bring in a stool sample with your cat’s annual check-up.

Adult worms live in the cecum – a C-shaped portion of the large intestine where the small intestine meets the large intestine. In heavy infections, they can also live in the ilium, which is the final portion of the small intestine and the colon where they release larvae.

The head burrows into the mucosal tissue of the intestine and absorbs blood and nutrients. The tail of the worm is free in the lumen of the intestine releasing eggs that are passed through the stool. The tail “whips” back and forth as ingesta move through the large intestine, giving the parasite the common name “whipworm”.

Eggs passed through the feces and are deposited in the environment. Once outside the body, an embryo will form within the egg. The egg becomes infectious after an embryo has formed within it, a process that usually takes two to four weeks.

The signs of whipworm infection vary depending on the number of worms the cat hosts so if there are only a few worms, many cats won’t have any signs.

A cat ingests an embryonated egg and becomes a host to the whipworm. The embryonated egg hatches in the small intestine of the cat where it lives for about a week before moving on to the large intestine and cecum. The whipworm will feed for about three months before it starts producing eggs.

Symptoms of Whipworm

Clinical signs of whipworm infestation vary depending on the number of worms the cat hosts. If there are only a few worms, many cats won’t have any signs. Cats with a larger number of worms can develop bloody diarrhea with straining and frequent, urgent bowel movements.

The diarrhea is often watery and may contain fresh blood and mucus. If the worm burden is heavy enough, the kitty may lose large amounts of protein through the intestinal tract, causing weight loss, lethargy, anemia and a potbellied appearance due to fluid build-up in the abdomen.

Heavy numbers of whipworm can cause intestinal obstruction or cecocolic intussusception, a telescoping of the intestine into the cecum, both of which are life-threatening conditions.

Whipworm infections can be challenging to diagnose since they do not produce large of a volume of eggs and also it can take up to three months before they release eggs in the stool.

How To Treat a Whipworm Infection 

Whipworm infections can be challenging to eliminate for a couple of reasons. The infectious eggs can survive in the soil for up to five years. Unlike other parasites, their eggs are not killed by freezing temperatures or dry conditions. This can lead to recurrent re-infections from the pet’s environment, such as a litter box.

In addition to the heartiness of the egg, whipworm infections can be challenging to diagnose. Parasites are usually identified by finding the eggs in a feces sample. Whipworms do not produce as large of a volume of eggs as other parasites. Also it can take up to three months before they release eggs in the stool. Both of these factors make it more challenging to diagnose a whipworm infection.

Treatment for feline whipworms involves deworming with either fenbendazole or febantel daily for three consecutive days. Because of the lifecycle of the whipworm, treatment should be repeated three weeks after the initial treatment and again three months later. Milbemycin is also used to treat whipworm infection.