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A lesson on cleaning up dog waste after Toxocara takes boy's sight in Ireland

Irish father urges people to clean up their dog's waste
Irish father urges people to clean up their dog's waste
Photo by Darren McCollester/Getty Images

Although this family tragedy occurred overseas in Northern Ireland, it clearly can happen anywhere man's best friend does his business.

In a story published in the Carrick Times on Feb. 7, father of a teen son, Michael Clarke recounts what happened to his 14-year-old boy, Cameron last year that caused him to loose sight in one of his eyes.

Cameron picked up the roundworm, Toxocara canis prompting his dad to call on neighbors to be mindful of cleaning up dog waste.

Michael said: “We have no idea where our son picked up the infective Toxocara eggs. He could have picked it up from anywhere. This news has had a terrible impact on our family, especially our son who already has a number of other health conditions. We don’t want another family to go through what we have and would urge all dog owners to worm their animals regularly and to clean up after their dog.”

There are so many reasons to teach young children to keep their fingers out of their mouths and not to eat dirt. Add the fact that there are so many dogs and puppies using our yard for a bathroom; your own, a neighbors, even a stray.

In the United States, most puppies and many adult dogs are infected with the roundworm, Toxocara canis.

Infection of the adult dog with this parasite happens when they ingest eggs from the contaminated environment. The puppies usually get this parasite from the mother before birth through her milk. The puppies will start passing eggs in their feces by 3 weeks of age.

This parasite can be spread to humans by ingestions of eggs from the soil or from contaminated hands. Most at risk are young children under 5 years of age, especially those with a history of eating dirt and exposure to puppies.

One study showed that 20-60% of soil samples from backyard residences, public parks and children’s sandboxes were contaminated with Toxocara canis eggs. Though it is found throughout the U.S., diagnosis of disease in children is made most frequently in the south.

Light infections in humans are usually asymptomatic, and probably occur quite frequently.

Human infection with Toxocara usually takes one of two forms; visceral larval migrans (VLM), this is where the larvae migrate aimlessly. They usually end up migrating to the liver, but almost any tissue can be invaded.

The other rarer manifestation is ocular larval migrans (OLM), where the larvae enter the eye where permanent vision loss is possible.

The diagnosis of Toxocara is usually based on clinical signs, history of exposure to puppies, laboratory findings (including eosinophilia), and the detection of antibodies to Toxocara. Stool samples are not useful for examination since the larvae don’t mature to adults in humans. Anti-parasitic drugs are available for treating VLM. You cannot treat OLM with antiparasitics and is usually left to trying to prevent more damage to the eye.

The best thing to do is increase prevention by reducing the accidental ingestion of eggs.

Prevention measures include:

• keep the dogs & puppies under a veterinarian’s care for early and regular deworming
• clean up after the pet and dispose of stool
• keep animals’ play area clean
• wash hands after playing with dogs or cats
• keep children from playing in areas where animals have soiled
• cover sandboxes to keep out animals
• don’t let children eat dirt.

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