When I was a vet student (which now seems such a long time ago), I remember the lecture we had on canine distemper. This disease was presented as “the disease of homeless people’s dogs”. Indeed, since vaccination for canine distemper virus became available, the number of clinical cases dramatically – and fortunately- decreased to a point that this is something we rarely see in private veterinary practice. However, you guys know by now that shelters are different.
I watched a webinar earlier this week on how to deal with canine distemper outbreaks in shelters. Must admit that my first impression was to think that yes, it can happen for sure – because we know that shelters are definitely highly predisposed to encounter any kind of infectious diseases- but that it should not be that common. One of the first slide of this excellent presentation showed a series of headlines regarding outbreaks of distemper in shelters in North America. Wouah… Never imagined that it could be so common and that it is unfortunately one of the major cause of shelter depopulation. Does not sound like a disease that anybody would like to ever face for sure, and that’s why as usual I truly encourage you guys to take some time to watch this great webcast. And as usual, for those of you who are in a rush (because in shelters, time is certainly the most difficult thing to find!), you can read my notes below!
It takes time to build an immune response for canine distemper
#1: Canine distemper is NOT a disease from the past. Outbreaks in shelters occur every year.
#2: It is because of vaccination that we do not see canine distemper more often in our veterinary clinics. However, 30-50% of dogs entering shelters have NO immunity for canine distemper virus.
#3: When it comes to dogs less than a year, 83% of them have NO immunity for canine distemper when they enter the shelter.
#4: After vaccination, it takes time for the animal’s organism to build up a strong immune response.
#5: 47% of adult dog will be protected 14 days after vaccination. 98% of them will be protected after 28 days.
#6: In puppies, the figures are quite different. Only 21% of them will be protected 14 days post-vaccination, and 66% 28 days after.
Clinical signs not always evocative…
#7: Canine distemper virus leads to a systemic infection. Several different clinical signs can be observed (GI signs, skin issues, respiratory signs, neurological signs,…), which are often misleading.
#8: Respiratory symptoms seem to be what is most often observed in shelters.
#9: Bottom line: clinical signs are NOT sufficient to rule out distemper. Infection must be documented and tested to move forward.
#10: PCR on swabs from the upper respiratory tract are now the fastest way to diagnose the infection.
#11: It was said in the past that it was really hard to save dogs suffering from distemper. However, we now have efficient medical treatments that allow us to save most of them.
#12: However, treatment is resource and time intensive. Shelter must be prepared to keep the dogs in excellent containment for 1-3 months. Strict biosecurity protocols and dedicated staffing are required, as well as sufficient medical support.
#13: Best alternative in shelter environment when it comes to treat infected animals: send them to a foster home where there are no susceptible pets and ensure that medical care will be supervised by a veterinarian.
Dogs will shed the virus for a long time after recovery
#14: Virus shedding continues for variable period of time after clinical recovery: average shedding time for dogs with low virus count was 3 weeks.
#15: When dealing with a higher virus count, the shedding last for an average of 6 weeks after clinical recovery.
#16: Another way to look at it: 50% of infected dogs shed virus for 5 weeks (1-15 weeks) after initial infection.
#17: Incubation period can last from 1 to 4 weeks. If a quarantine is required for dogs that are suspected of being infected by the virus, this one should therefore last 4 weeks.
#18: Something to keep in mind: every time a dog in quarantine breaks to clinical signs, the quarantine clock starts over, unfortunately.
DR. EMMANUEL FONTAINE 