Gastrointestinal roundworm parasitism in coatis

What is it?

Gastrointestinal parasitism caused by roundworms (nematodes) is a very common condition in coatis, whether living in their natural habitat, in zoos, or in private captivity. The infection involves the intestines and is caused by worms from the Ascaris family or other related nematodes, which live at the expense of the animal and feed partly on its digestive contents.

This disease particularly affects young coatis, which are more vulnerable, but it can occur in animals of any age, especially when enclosure hygiene is poor.

In most cases the infestation remains mild, but it can become severe in weakened animals, those under stress, or those living in dense groups, as often happens in captivity.

Commonly observed signs

These signs are neither exhaustive nor specific. Only a veterinarian can establish a diagnosis.

Causes and risk factors

The disease is caused by intestinal nematodes, which are unsegmented roundworms. The most commonly reported in procyonids (the coati family, which also includes raccoons) belong to the genus Baylisascaris or related genera such as Toxascaris.

These worms lay eggs that are highly resistant in the environment and are then ingested by a new animal through grooming, licking the ground, or eating contaminated food.

Young age is a major risk factor, as young coatis are more susceptible and develop more severe infestations.

A dirty environment, poorly cleaned enclosures, high animal density, or poor hygiene promote the spread of worm eggs.

Stress, unbalanced nutrition, or another concurrent disease weakens the animal's immune defenses and worsens the infestation.

Contact with rodents or other small animals carrying larvae can also play a role, as some nematodes have a life cycle involving an intermediate host.

Diagnosis and care

Diagnosis is the veterinarian's responsibility, based on clinical examination and laboratory tests. Care is decided case by case.

Treatment

Treatment relies on broad-spectrum anthelmintics active against intestinal nematodes. The choice of drug, route of administration, and treatment duration should be determined by a veterinarian experienced with exotic animals, as coatis may be sensitive to some products used in other carnivores.

Supportive care, such as rehydration or nutritional support, may be needed in debilitated animals.

Prevention

Possible complications

Severe untreated infestation can cause intestinal obstruction from worm accumulation, severe dehydration, significant weight loss, and in young or weakened animals, risk of death.

Some Baylisascaris nematodes can migrate to other organs, including the nervous system, with serious consequences.

When to see a veterinarian

Transmission to humans

Some nematodes found in procyonids, particularly Baylisascaris, can rarely infect humans, especially children, through accidental ingestion of eggs from contaminated environments. While this transmission remains uncommon, it can be serious; therefore, good hand hygiene after handling animals or their environment and thorough enclosure cleaning are important.

Prognosis

The prognosis is generally good when the infestation is detected early and treated appropriately.

It becomes more guarded in cases of heavy infestation, in young animals, or when complications such as intestinal obstruction are present.

Frequently asked questions

References

ESCCAP — European Scientific Counsel Companion Animal Parasites

CDC — Centers for Disease Control and Prevention

WOAH — Organisation mondiale de la santé animale (ex-OIE)

Content reviewed by the TunisieVet editorial team · Updated 02 September 2026