Caring for pets belonging to immunocompromised clients (Proceedings)

• Recognize that nearly all practicing veterinarians care for pets of immunocompromised clients.

• Be aware of, and provide education for clients and staff, regarding potential health risks associated with pets.

• Develop specific plans for health maintenance of pets of immunocompromised clients.

Increasing numbers of human beings are immunocompromised as a result of illness or the use of immunosuppressive drugs, and it is estimated that at least 30% to 40% of immunocompromised patients own companion animals. Zoonotic and opportunistic infections can be acquired from companion animals, and pet owners who are immunocompromised may not be aware that they may be at risk of acquiring infections from their pets or other animals. Only 10% of 187 AIDS patients who were pet owners had been informed about zoonotic diseases by health care workers, and 4 of these were informed only after being diagnosed with infections that were considered possible zoonoses. It should be emphasized that although pets can be a risk factor for acquisition of zoonotic and opportunistic infections in immunocompromised people, there is not good support for recommendations that such people relinquish their pets in order to improve their own health. Results of one survey showed that patients with AIDS-defining diseases known to be common to animals and human beings were just as likely to be non-pet owners as they were to own pets.

Pets are an important source of camaraderie and support for many immunocompromised people. Pets provide comfort, companionship, and an improved sense of self-worth for HIV-infected patients. Pet ownership also has been shown to benefit the elderly, foster social and verbal interaction among children, and contribute to development of nurturing behavior and responsibility in children. Other health benefits of interactions with pets include: reportedly improved overall health with fewer visits to physicians by elderly pet owners compared to non-pet owners, lowered blood pressure and triglycerides of pet owners compared to non-pet owners, and increased 1-year survival times following myocardial infarction in pet owners compared to non-pet owners. Segregation of immunocompromised people, the elderly, or children from pets is not generally necessary to prevent transmission of zoonoses, and is often the least acceptable means of preventing such transmission. Veterinarians and physicians must be prepared to discuss pet ownership and the bona fide risks for acquisition of zoonotic or opportunistic infections with immunocompromised people, and provide sound plans for maintenance of the health of pet animals and their owners.

In addition to concern for the health and well-being of patients, clients and employees, practitioners should also be aware of potential legal implications of not properly informing clients and employees of the possible risks of zoonotic diseases associated with handling companion animals. Steps recommended to decrease liability include: 1) Keep current on zoonotic disease processes and contemporary standards of care, 2) Educate clients and staff thoroughly regarding the risks, and 3) Keep good records and follow up with clients and staff to help ensure that recommendations are being followed. A specific plan should be developed for each client's companion animals. Some agents are likely to be transmitted directly from companion animals to human beings, whereas others are more likely to be transmitted from a common source in the environment.

Plans and implementation

Increasing client awareness

Posters and brochures are available from the Centers for Disease Control (CDC), Humane Society of the United States, and other organizations such as Pets Are Wonderful Support (PAWS). These may be prominently displayed in client waiting areas, examination rooms, and staff work / lounge areas. Specific training should be provided for veterinary staff to increase their understanding of zoonotic diseases and opportunistic infections for their own protection and so that they may more effectively communicate with clients. Take advantage of opportunities for client education that occur in common office call situations such as wellness exams for puppies, kittens and other pets, yearly examinations of pets, and evaluation of animals with clinical signs suggestive of possible zoonotic diseases.

Increasing veterinarian and physician awareness

Veterinarians and physicians should be knowledgeable about what animals are the most appropriate pets for immunocompromised people. The CDC has published guidelines, and some guidelines are also available the AVMA and from other organizations such as PAWS. For example, healthy adult animals with known good health histories are acceptable pets, whereas stray animals and young animals are at greater risk for carriage and transmission of infectious agents and should be avoided. Animals without complete health records available are not generally acceptable. Health records should be available and reviewed for all candidates for adoption or purchase by immunocompromised clients. Special efforts should be made to educate children in good hygienic practices and about the risks of acquiring infections from pets. Reptiles, amphibians, and primates should not be kept as pets by immunocompromised people, because of the risk of transmission of diseases such as salmonellosis and tuberculosis.

Maintenance guidelines

New pets should be examined by veterinarians when acquired, and screened for intestinal parasites and ectoparasites. Cats should be tested for feline leukemia virus and feline immunodeficiency virus. Cats that have potentially immunosuppressive conditions may not make good pets for immunocompromised clients because these cats may themselves be more susceptible to infection with zoonotic agents or opportunistic organisms. Develop vaccination protocols for pets based on geographic region and other relevant exposures, and establish a schedule for regular veterinary evaluation of pet health. Aggressively pursue identification of the etiologic agent(s) of parasite infestations, diarrheal conditions, respiratory diseases, and any apparent bacterial infections of pets, and institute timely, thorough treatment for any of these conditions. Counsel clients treating ill pets to use caution and to wear gloves when administering medications to pets and when cleaning the pets or the environment.

Feed only good quality commercial diets. No uncooked materials should be fed, such as raw or undercooked meats of any kind, unpasteurized dairy products, and raw or undercooked poultry products. Pet animals should not be allowed to roam free or to hunt, including chasing flies or other insects. Toilet bowls should be kept closed so that pets cannot drink from them. Pets should not have access to table scraps or garbage, and copophragy should be discouraged. Pets that are allowed outdoors should go outside only when on a leash and under human supervision. Cat litter boxes and bird cage linings should be cleaned daily; gloves should be worn for these tasks and care taken not to create aerosols or fine dust while cleaning.

Pets should be groomed regularly, either professionally or by owners, and flea and tick infestations promptly eradicated. Ectoparasite prevention strategies should be used for all pets. In climates or seasons that require it, pets should be examined daily and any ticks carefully removed and disposed of. Clients should receive instruction on proper tick removal and disposal to avoid exposure to tick-transmitted pathogens. Cat claws and dog toenails should be kept trimmed.

Emphasize good hygiene practices, and recommend that clients wear gloves when cleaning fish tanks, or when gardening or handling objects contaminated with feces, urine, or vomitus. Hands should be washed before and after handling uncooked foods and before and after handling pets. When bite or scratch wounds occur, they should be washed immediately and medical attention sought.

Recommendations that immunocompromised patients relinquish their pets are rarely indicated. As previously noted, one study showed that patients with AIDS-defining diseases known to be common to animals and human beings were as likely to be non-pet owners as they were to own pets. The benefits of pet ownership for all clients, including immunocompromised people, are great. Working together, veterinarians, clients, and others in the community can provide extraordinary service by helping to maintain the health and well-being of immunocompromised people and their pets.

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