Ferrets are susceptible to both the rabies virus and canine distemper virus. These viruses produce serious illness in the ferret that usually results in death within three to four weeks of infection. There is no treatment for rabies or distemper in the ferret. However, both of these diseases are preventable through a program of regular vaccinations using the appropriate vaccine product. Generally, these vaccines are safe and effective when used correctly.
All ferrets are susceptible to rabies, although the incidence of naturally occurring rabies in pet ferrets is very low. Rabies is acquired through contact with the saliva of an infected (rabid) animal. This usually means an outdoor ferret that picks a fight with a wild animal like a raccoon, bat, fox or a stray rabid cat or dog.
The only approved rabies vaccine for ferrets is Imrab 3 (Merial). This vaccine can be given to ferrets three months of age and older and is then administered yearly. It is often given in conjunction with the distemper vaccine. The rabies vaccine is given subcutaneously (under the skin; SQ) of the upper back area (the scruff).
Adverse reactions are unusual with the rabies vaccine. While any vaccine product can elicit an allergic-type reaction, this is rarely seen with the rabies shot. Distemper vaccines are more often associated with reactions in ferrets (see below).
Check with public health department officials concerning the status of ferret ownership. Some states do not consider that pet ferrets are domestic animals and these states may not recognize the rabies vaccine. In these cases, if a ferret bite is reported, the ferret may be confiscated and checked for rabies even if already vaccinated with an approved product.
All unvaccinated ferrets are susceptible to infection with the canine distemper virus. Susceptible ferrets that are exposed to the distemper virus start showing symptoms in seven to 10 days and usually die within several days of getting sick. There is no cure. Fortunately, this disease is becoming increasingly less common due to vaccination programs.
The vaccine is administered SQ in the skin behind the back of the neck (the scruff). Vaccines begin at six to eight weeks of age and boosters are given again at three to four week intervals until the ferret is 16 weeks old (8-12-16 weeks of age). The vaccine is then given yearly. Adult ferrets not fully immunized as juveniles, should receive two injections three to four weeks apart and then annual boosters.
It is especially important for ferrets to get the correct distemper vaccine product. Because the vaccine contains a live virus, administration of the wrong product can cause the ferret to develop the disease. There are two products that are considered safe: Fervac® (United Vaccines) and Galaxy-D® (Solvay). Fervac is the only product labeled for use in ferrets but many ferret shelters and veterinarians use the Galaxy-D. Other products may be available in the future.
There is always a risk of an adverse response or reaction to a vaccine. While the rabies shot can result in an injection reaction, this is seen more commonly with the distemper vaccines.
The vaccine reaction is an allergic-type response that is characterized by profuse vomiting, diarrhea, and lethargy. The reaction usually occurs within 12 hours of the shot and most cases are within the first 60 minutes.
Your veterinarian must administer treatment for a vaccine reaction as soon as possible. Steroids, antihistamines, and sometimes epinephrine must be given by injection to the affected ferret. Most reactions are controllable with these drugs and most ferrets quickly respond to treatment. Ferrets that have vaccine reactions are still protected against the virus.
The decision to re-vaccinate a ferret with a history of past reactions should be discussed your veterinarian. One must weigh the potential risks of vaccine reactions against the risk of contracting the distemper virus.
Following vaccines, it may be prudent to wait in the veterinarian's office for 30-60 minutes to observe for any reactions to the shots. Observe your vaccinated ferret for the rest of the day and report any unusual behavior to your veterinarian.