Roundworms

Roundworms are a common zoonotic (transmissible to people) intestinal parasite of puppies and kittens; they can also infect adult pets. Infection is acquired through different mechanisms:

Transplacental (before birth): this form is the most common; 95% of puppies are born with roundworms. The stress of pregnancy causes encysted roundworms to emerge.
Nursing from an infected mother dog/cat
Hunting behavior: Eating the flesh of an animal infected with roundworms
Environmental contamination from the stool of an infected animal
Symptoms of roundworm infection range from asymptomatic to diarrhea and unthriftiness (poor hair coat, thin). Diagnosis of roundworm infection is made by identifying roundworm eggs in a fecal sample. Regular deworming practices are of paramount importance to prevent transmission to people, other animals, and reinfection. Roundworms are easily killed with deworming medications prescribed by your veterinarian. To reduce the risk of infection, treat all of the pets in your household and pick up your pet’s feces immediately. Your pet should be bathed to remove roundworm eggs attached to the fur. Diligence should be taken with hand washing. Following treatment, your veterinarian will want to do a follow-up fecal examination on your pet to ensure that the roundworm infection has been cleared.