Infectious diseases are continuous challenges for animal shelters. Unfortunately, outbreaks are not uncommon. Sometimes they’re the result bad luck and the inherent risks involved in bringing together lots of animals of questionable health status from different sources. However, if you compound these risks with things like inadequate facilities, overcrowding, poor training of personnel, poor adherence to protocols, bad protocols, lack of awareness about infectious diseases and failure to get expert help early in any outbreak, the likelihood of "badness" increases.
A few shelter outbreaks are underway at the moment, and they highlight some of the infectious disease challenges posed by different diseases in animal shelters.
- The Oakville and Milton Humane Society (in Ontario) is closed because of a ringworm outbreak that’s been going on since early September. Ringworm, while of limited health consequences, is an important shelter problem because it’s common, highly transmissible, can be hard to control and can infect people. At last report, 22 cats were confirmed or suspected to have ringworm, along with at least four staff members. It’s not clear who’s coordinating the outbreak response, but hopefully they’re getting good advice and they’ve read the comprehensive report from the Newmarket OSPCA ringworm debacle.
- 72 kittens were euthanized in the Miami-Dade County Animal Services because of "cat plague," which is a common name for feline panleukopenia. This viral disease is preventable by vaccination, but it’s a serious concern in shelters were there are often lots of unvaccinated or inadequately-vaccinated cats and lots of susceptible kittens. In this shelter, all cats with clinical signs consistent with panleukopenia are being euthanized. Euthanasia is always a tough decision, but with a serious disease like this, it’s a reasonable response. Outbreaks like this highlight the need for excellent infection control practices to reduce the risk of spread of pathogens like this once they make it into a shelter.
- Upper respiratory tract infections have resulted in suspension of adoptions at the Bergen County Animal Shelter in New Jersey. News reports are calling it a canine influenza outbreak, and canine flu is definitely on the list of possibilities, but it doesn’t sound like it’s been confirmed. Respiratory infections are a common cause of problems in animal shelters because some causes (e.g. canine parainfluenza virus, canine influenza virus) are quite transmissible. Canine flu poses extra challenges when it moves into a new area, since few if any dogs have antibodies against the virus and therefore it can spread rapidly. The report also mentions transmission by dogs not showing signs of disease. That’s a problem with some infectious agents. For example, with canine flu, dogs tend to be able to shed the virus before they show signs of illness. Therefore, there’s a period of a couple of days after infection but before disease where you can have a silent reservoir of infection. That’s why quarantine of new admissions is critical, since it gives animals a few days to show signs of diseases they may be brewing at the time of admission. (Unfortunately, it’s not easy to find space in which to quarantine an animal in an overcrowded shelter.)
A common denominator in all of these outbreaks is the potential that something could have been done differently to prevent the problem. It’s possible (although unlikely) that everything that was done perfectly, however it’s a rare outbreak where you can’t find multiple areas for improvement. A key aspect of outbreak management is, once the crisis is over, performing an investigation of what really went wrong and why, and taking measures to reduce the chance of it happening again.
Image: Ringworm infection in a cat is not always readily apparent, but in some cases can cause obvious patches of hair loss.