Visceral larva migrans is a human infection with certain parasites found in the intestines of dogs and cats.
Toxocariasis; Ocular larva migrans; Larva migrans visceralis
Causes, incidence, and risk factors
Visceral larva migrans (VLM) is caused by worms (parasites) that are found in the intestines of dogs and cats. The dog parasite is called Toxocara canis and the cat parasite is called Toxocara cati.
Eggs produced by these worms are in the feces of the infected animals. The feces mix with soil. Humans can get sick if they accidentally eat soil that has the eggs. This can be through eating fruit or vegetables that were in contact with infected soil and not washed thoroughly before eating. People can also become infected by eating raw liver of chicken, lamb, or cow.
Young children with
After the worm eggs are swallowed, they break open in the intestine. The worms travel throughout the body to various organs, such as the lungs, liver, and eyes. They may also travel to the brain and heart.
Mild infections may not cause symptoms.
Serious infections can cause the following symptoms:
- Abdominal pain
Itchy skin (hives)
- Shortness of breath
If the eyes are infected (called ocular larva migrans), loss of vision and crossed eyes (
Signs and tests
If you have visceral larva migrans, you may have a high level of white blood cells.
People with this condition may also have signs of a swollen liver, rash, and lung or eye problems.
Tests may include:
Complete blood count with differential
Blood tests to detect antibodies to Toxocara
This infection usually goes away on its own and may not require treatment. Some people need to take anti-parasitic drugs such as albendazole.
Mild infections may go away without treatment. Severe infections involving the brain or heart can result in death, but this is rare.
Blindness Decreased visual acuity(worsened eyesight)
- Encephalitis (infection of the brain)
- Heart arrhythmias
Calling your health care provider
Contact your health care provider if you develop any of the following symptoms:
A full medical exam is needed to rule out visceral larva migrans. There are many conditions that cause similar symptoms.
Prevention includes deworming dogs and cats and preventing dogs and cats from defecating in public areas. Children should be kept away from areas where dogs and cats may defecate.
It is very important to wash your hands thoroughly after touching soil or after touching cats or dogs. Teach your children to wash their hands thoroughly as well after being outdoors or after touching cats or dogs.
Do not eat raw liver of chicken, lamb, or cow.