Module 5: Management and Prevention of Disease Outbreaks
Several disease outbreak parameters should be documented to aid in diagnosis, to determine whether the infection was contracted outside of the shelter or acquired in the shelter, for containment strategy planning, to assess the effectiveness of the strategy, and identification of the weakness in the system that enabled the outbreak.
Start with the index case (first recognized case) by answering these questions:
- How many days in the shelter before illness?
- Vaccination dates?
- Housing location?
Important parameters to track during the disease outbreak include:
- Dates of illness for each animal
- Clinical signs observed
- Duration of illness for each animal
- Number of sick animals
- Number of exposed animals
- Age of sick and exposed cases
- Vaccination dates for sick and exposed cases
- Housing location of sick and exposed animals
- Cases confirmed by diagnostic testing
- Suspect cases not confirmed by diagnostic testing
- Where did the first sick animals come from and where were they initially housed
Trace-Back for Identifying Potentially Exposed Animals
A trace-back method can be used to identify animals that may have been exposed to the initial cases during their preclinical shedding period. The trace-back time frame is the maximum incubation period of the diagnosed pathogen: simply count back the number of days from the first identified sick animal. If any of the potentially exposed animals were released to adopters and pet placement partner agencies during this trace-back time, they should be notified and provided a written statement explaining what to do if infection is suspected or diagnosed, including who to contact at the shelter and whether the shelter is accepting animals back or assuming financial responsibility for veterinary treatment.
- Using the incubation period, count backwards from the dates of identification of sick animals
- Determine what animals were in the shelter at this time but have since left for homes/rescue groups
- Contact adopters and rescue groups to notify them of what the animal may have been exposed to, what signs to watch for, what steps to follow if the animal becomes sick
Review Current Practices
Protocols for intake processing, vaccination, sanitation, daily monitoring of animal health, and isolation of sick animals should be evaluated and updated to include best practices. Responsible staff should be trained, supervised, and held accountable for the practices. To mitigate risk for recurrent outbreaks, a daily disease surveillance and monitoring protocol should be implemented for prompt identification and isolation of sick animals followed by examination and diagnostic testing to determine cause.