UC Davis Koret Shelter Medicine Program

Diagnostic testing is sometimes underutilized in shelters because of the sense that it is unaffordable. In fact, investment in appropriate diagnostics can save a lot of money, time and animal lives by rapidly identifying the cause of illness and permitting appropriate treatment and management measures to be implemented. Diagnostic testing is indicated when:

• Unusually severe, frequent, or apparently vaccine or treatment resistant disease is found in a population
• Zoonotic or cross species disease transmission is suspected
• An individual animal does not respond to treatment as expected

Diagnostic options include in-house procedures such as fecal floatation, ELISA ("snap") testing for specific pathogens, and in-house bloodwork. Some shelters also perform culture in-house for fungal or selected bacterial infections. Laboratory diagnostics include microbial isolation via culture and PCR panels to detect a variety of pathogens. In-house necropsy combined with laboratory analysis of samples can be a powerful method to rapidly diagnose the cause of an outbreak.  The best diagnostic choice depends on the number of animals affected and whether a specific disease is suspected or whether the causative agent(s) is unknown.

We offer outbreak consultation services at an hourly rate; for these services or more information contact us at sheltermedicine@ucdavis.edu. Please make a note in your subject line if the matter is urgent. For additional resources on management of outbreaks and collection of diagnostic samples on necropsy, see chapters 3 (outbreak management) and 7 (necropsy) of the textbook Infectious Disease Management in Animal Shelters (Hurley and Miller, published by Wiley-Blackwell, available at Amazon.com among other online sources).

Real-time -PCR panels and interpretation of results

The Koret Shelter Medicine Program and IDEXX Laboratories have teamed up to make infectious disease surveillance more accessible to animal shelters. IDEXX Reference Laboratories is offering their feline and canine respiratory and diarrhea panels using real-time PCR (RealPCR^TM) at a 50% discount for shelters. Such a deal! For program details, Please contact IDEXX Molecular Diagnostics Laboratory directly.

The advantage of  real-time-PCR panels is that they cover a number of potential pathogens and are highly sensitive for detecting presence of pathogens in acutely affected animals. One aspect to bear in mind, however, is that presence of a pathogen does not necessarily indicate a cause-and-effect relationship. Many of the pathogens contained in the Idexx panels can also be isolated from normal, healthy animals with moderate frequency (e.g. Bordetella, herpesvirus, and calicivirus). In addition, recent modified live vaccination sometimes causes positive results on PCR. Therefore, test results should be interpreted in the context of clinical signs in the tested individuals and population; the vaccination history of the tested animals; and the overall prevalence of pathogens in the sample population versus expected levels in a shelter environment.

If you have submitted real-time -PCR panels from a shelter to IDEXX and would like our input on interpretation of test results, please use our "ask shelter medicine" page. As we gather more information about rates of pathogen isolation on panels from shelter animals, we will share that information on this web site.