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Professional Version

Veterinary Medicine Within the Animal Shelter


Martha Smith-Blackmore

, DVM, Cummings School of Veterinary Medicine, Tufts University

Reviewed/Revised Oct 2021 | Modified Nov 2022

Principles of sound shelter health practices include evaluation of the incoming animal at the time of intake to identify specific needs of the individual animal; preventive medicine measures such as vaccination and parasite treatment; testing for detection of prevalent infectious diseases; appropriate cleaning and disinfection to minimize disease transmission within the facility; stress management and reduction; and population management to ensure that the shelter operates within its capacity for care. Protocols for any given shelter are shaped by the available resources, the needs of the population, and the mandate or mission of the organization.

Veterinarians can help by developing programs to move animals through the shelter system efficiently and by providing expedient medical care. Veterinarians can also assist in developing appropriate behavioral rehabilitation programs, so that resident animals can enjoy a high quality of life during their shelter stay. These measures reduce the impacts of infectious disease. Numerous studies have shown that length of stay in a shelter is the single greatest risk factor for illness, and stressed animals do not “show” well on the adoption floor. Therefore, providing both medical and behavioral care is essential to shelter population health.

Unless the animal shelter is intentionally a longterm, sanctuary-care facility, the focus should always be on moving the animals through the shelter system quickly and minimizing their length of stay. In so doing, the animal shelter organization simultaneously maximizes its lifesaving and animal welfare potential.

Intake Evaluation Within the Animal Shelter

All animals should be assessed for health and behavioral needs as soon as possible after arriving at the animal shelter. If possible, a detailed history should be taken from the surrendering party or anyone who knows the animal (ie, a neighbor or a prior owner identified by microchip scan). This triage helps to define the specific animal’s medical and behavioral needs. This get-to-know-you process should include a veterinary examination and reports of observed behavior from all who interact with the animal. By seeing each animal as an individual and planning for what will help that animal the most, the shelter can facilitate the animal’s pathway through its facility to a good outcome (eg, adoption or transfer to a partner organization). In some instances, the identified problems will be treated in the sheltering facility; in other cases, problems will be detailed so that the receiving party can provide care and treatment.

A variety of behavior evaluation tools have been developed to help identify the risk of future aggression in dogs and the individual behavioral support needed before and after adoption. One frequently used evaluation is SAFER® (Safety Assessment for Evaluating Rehoming) from the American Society for the Prevention of Cruelty to Animals (ASPCA). Formal behavior evaluations should be performed after the animal has had time to settle into the shelter. Evaluations should be implemented in a standardized manner each time, minimizing the effect of different evaluators, the setting, and other distractions. Information from assessments may help inform decisions on safety and adoptability. Behavior evaluations performed in the animal shelter may not identify problem behavior in the home and may exacerbate behaviors that will resolve in a home setting. Therefore, behavior evaluation results should be interpreted with caution. Daily-care staff, volunteers, and foster homes can provide other important information from socialization sessions, walks, and playgroups.

Vaccination Upon Intake Within the Animal Shelter

A cornerstone of animal shelter health is the principle of vaccination upon intake with recommended core vaccines, as well as additional vaccines known to be necessary in a given population or community. This practice should give the immunologically naive animal the opportunity to develop immunity against infectious diseases before it encounters an infective dose of a natural disease within the facility. The core vaccines recommended for dogs include modified live or recombinant canine distemper Canine Distemper Canine distemper is a highly infectious, systemic, viral disease of dogs that occurs worldwide. Dogs commonly exhibit systemic clinical signs (fever, lethargy, loss of appetite), respiratory... read more virus, adenovirus-2 and parvovirus (DAPP); Bordetella bronchiseptica and canine parainfluenza virus; and rabies Rabies in Animals Rabies is an acute, progressive encephalomyelitis caused by lyssaviruses. This zoonosis occurs worldwide in mammals, with dogs, bats, and wild carnivores as the principal reservoirs. Typical... read more Rabies in Animals virus (killed). Canine influenza Canine Influenza (Flu) Canine influenza is spread by dog-to-dog by aerosolization of two strains of the canine influenza virus (H3N8 and H3N2), as well as by contaminated objects and fomites. Most infections are mild... read more (H3N8 and H2N2) vaccination may be indicated, depending on local prevalence.

The core vaccinations recommended for cats include modified-live parenteral panleukopenia Feline Panleukopenia Feline panleukopenia is a parvoviral infectious disease of kittens typically characterized by depression, anorexia, high fever, vomiting, diarrhea, and consequent severe dehydration. Adult cats... read more virus, intranasal or parenteral herpesvirus-1, calicivirus (FPV, FHV-1, FCV), and rabies virus (recombinant or killed). Feline leukemia Feline Leukemia Virus Disease Feline leukemia virus (FeLV) is one of the most common infectious causes of disease of cats globally. Infection with FeLV can cause a variety of clinical signs, impacting a cat's longevity and... read more Feline Leukemia Virus Disease vaccination is also recommended for facilities that group-house kittens and cats. Bordetella vaccination may be indicated during outbreaks among dogs within the facility.

For diseases of concern in animal shelters, vaccines may be indicated at an earlier age and administered at shorter intervals compared with schedules for pets in homes. It may be advisable to vaccinate pregnant animals and animals with mild clinical signs of illness.

Rabies vaccines should be administered as state law, animal age, and access to a veterinarian allow. Any animal leaving a shelter for adoption, transfer to another organization, an offsite adoption event, foster care, or other activities that may expose the animal to new people or animals should be vaccinated for rabies.

Use of Parasiticidal Treatments Within the Animal Shelter

The routine administration of broad-spectrum preventive parasiticidal medications and treatments minimizes suffering and limits the transmission of certain infections and infestations. Preventive administration protocols should be tailored for infections and infestations of local concern. With the wide spread of the invasive Asian tiger mosquito (Aedes albopictus), most areas are now considered at risk for endemic heartworm disease Heartworm Disease in Dogs, Cats, and Ferrets Heartworm disease (dirofilariasis), produced by Dirofilaria immitis, primarily affects the pulmonary arteries, producing inflammation, vascular dysfunction, and pulmonary hypertension... read more Heartworm Disease in Dogs, Cats, and Ferrets . Heartworm (Dirofilaria immitis) screening for antigens, antibodies, and filariae may be appropriate, depending on local incidence and resources. Preventive mosquito mitigation is an important measure to limit the transmission of heartworm disease in an animal shelter. Parasite prevention programs for shelter animals also reduce the risk of zoonotic transmission.

Testing for Prevalent Infectious Diseases Within the Animal Shelter

Infectious disease screening programs, such as testing dogs for heartworm infection and tick-borne diseases and testing cats for retroviral diseases, or obtaining ringworm cultures upon intake, may be needed for some populations of animals. Screening programs should be tailored to reflect local threats and incidence. Screening may enable tracking of animals into early treatment programs to reduce the risk of transmission within the animal shelter, or to facilitate population management and decisions related to resource allocation.

When an animal is identified with an infectious disease that poses a likelihood of transmission within the shelter facility, appropriate steps to take may include isolation in place with specific treatment, cleaning, and handling protocols; or removal from the population (into a hospital, special ward, or foster home; or euthanasia). For diseases identified with known incubation periods, the timeline should be researched to ascertain whether the disease was acquired before arrival at the facility or within the facility. Disease transmission within the animal shelter requires a more rigorous population management and disinfection response. An individual expressing a community-acquired infection requires a more individually focused response and may highlight the need for targeted community outreach education and vaccination programs.

Rounds should be conducted once daily, at minimum, to visually inspect each animal, to ensure that they are not suffering from clinical signs of disease or distress. Animal caregivers should maintain a record on each animal to indicate food and water intake, eliminations, exercise, and attitude.

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