An infection with parasites generally leads to poor health in pets. Hookworms, roundworms (ascarids), whip worms and others can be contracted from the environment, your pet’s mother during pregnancy and lactation, leading to an infection of your pet. More importantly, hookworms (via direct cutaneous/skin penetration and migration) and roundworms (via ingestion of fecally contaminated sand, dirt, etc.) are important zoonotic diseases, meaning they have been shown to infect multiple species, in this case people. Vomiting, diarrhea, anemia, weight loss, coughing, lethargy, distended abdomen, bloody stool, and anorexia are common (but non-specific) clinical signs seen in animals with parasites. Sometimes it is possible to see worms in the feces, vomitus, or even around the tail area. If left untreated, parasitic infections can become severe enough to cause serious illness or even death.
Puppies and kittens (and their mothers if present) should be treated with appropriate anthelmintics (dewormers) when they are 2, 4, 6, and 8 weeks of age. Puppies and kittens should be put on monthly preventives that have efficacy against a variety of parasites as soon as label recommendations allow. If puppies and kittens are not treated until 6 to 8 weeks of age or later, they should be put on a monthly preventive according to label recommendations, dewormed again in 2 weeks, and then maintained on monthly preventives thereafter. Beginning treatment when puppies and kittens are 2 weeks of age will help minimize environmental contamination and future chances of infection as infective eggs can remain in the environment for years. It is then recommended that fecal examination 2 to 4 times in the first year and 1 to 2 times annually thereafter, depending on the age of the animal and its prior history of infection.