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Name: Joe A.
Status: Other
Age: 60s
Date: 7/16/2003

A number of years ago, one of the major TV channels ran a program that traced the bacteria from dog feces to the deaths of children. The process was the children playing in the area where a dog defecated, collected the bacteria on their hands which were placed in the child's mouth and an organism developed in the child's brain which eventually killed the child. Within the last month, one of the news channels carried a similar story. Do you know the name of the disease and could you please direct me to additional information on the above subject?

Toxacara Larva Migrans

Phillip Raclyn, DVM CVA

There are a number of disease causing agents that can be transmitted from dogs to people through the feces. From the description, this sounds like roundworms.

If a dog ingests the roundworm eggs, which are too tiny to see without a microscope, the eggs hatch into tiny larvae that migrate through the dog's intestinal wall, back to the intestine and develop into adult worms.

Since the human is not the right host for the parasite, the microscopic larvae that hatch can migrate into other parts of the body. Many people have been exposed to small numbers of these parasites without showing any disease signs. But exposure to large numbers of eggs can cause disease and in very rare cases of high exposure, many larva may migrate into the brain causing severe problems. Of even more concern than the dog roundworm is the raccoon roundworm, which seems to have a greater affinity for migrating to the brain.

Fortunately, these cases can be largely prevented by 1) making sure that children don't eat dirt or contaminated soil or wood chips, 2) having good hand-washing after contact with soil, 3) making sure that animals are unlikely to defecate in areas where children play and 4) having regular veterinary care for pets so that they are treated to kill and prevent worms.

Laura L. Hungerford, DVM, MPH, PhD

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