Carol Rubin of the Centers for Disease Control and Prevention in Atlanta said some diseases that pass between animals and people range from mild to very serious.
Pets can give their owners ringworm, cat scratch fever, rabies and toxoplasmosis. Meanwhile, humans can give animals multidrug-resistant staph aureus infection.
"Pet owners should make sure that their animals are vaccinated, especially against rabies. Pet owners should provide protection against external parasites like fleas and ticks," Rubin said in a statement. "Owners should also test and treat to control the internal parasites."
Rubin's study was published in the CDC's journal Emerging Infectious Diseases.
Babies and children age 5 and under are more likely to get diseases from animals. The CDC recommends:
-- Young children should not be allowed to kiss pets or to put their hands or other objects into their mouths after touching animals.
-- Wash a child's hands thoroughly with soap and warm running water after every contact with an animal.
-- Be particularly careful when visiting farms, petting zoos and fairs. Always wash hands after touching an animal.