Parasitic infections in household pets and human risks

Household pets can carry various parasitic infections that pose risks to both animals and humans.

Toxoplasma gondii is a single-celled parasite where cats serve as the primary definitive host. Cats become infected by consuming infected rodents or birds, subsequently shedding highly resistant oocysts in their feces. While other warm-blooded animals and pets can act as intermediate hosts by ingesting contaminated soil or food, cats are unique in their ability to shed infectious oocysts.

Toxocariasis, caused by roundworms such as Toxocara cati, is also common in cats. While often not life-threatening to the animals, the infection can spread to humans. Toxocara cati can be transmitted from mothers to kittens through milk or via environmental ingestion. Symptoms in cats may include vomiting, diarrhea, poor growth, and a ‘potbelly’ appearance in kittens. Toxocara leonina is another species that can infect cats but is less likely to cause disease and does not infect humans.