Before you decide you indoor-only cat does not need parasite prevention, please consider the following facts. 

* Cockroaches, mice and flies all can carry roundworm eggs. Cats are natural hunters and will hunt them!

* 15% of commercial potting soil contains roundworm eggs.

* The Northeast has the highest prevalence of roundworms than any other part of the country.

* Other animals in the household that do go outside - like dogs and people - can bring in different parasites that can affect the indoor cat.

* Children and immune-compromised people, such as cancer patients, people with HIV or AIDS and organ transplants, are more susceptible of being infected with these parasites. 40% of immune-compromised people have a pet at home.

*Roundworm or Toxocara cati, are prolific egg producers and are estimated to produce as many as 24,000 eggs per day. 

*A 2007 study conducted by the CDC proves that almost 14% of the U.S. population is infected with Toxocara - much higher than what was originally thought. This same study states "Although most persons infected with Toxocara have no symptoms the parasite is capable of causing blindness and other systemic illness."

*It is estimated that 3-6 million people in the United States may be infected with Toxocara (roundworm) larva migrant each year.

*In just 30 days, 25 female fleas can multiply to more than 250,000.

*All it takes is one adult worm in a cat's heart to be fatal. Cats that die from heartworm can be clinically normal one hour before death.

*More than 25% of cats with proven heartworm infection, according to their owners, are kept indoors exclusively.