Routine veterinary care for pet ferrets includes yearly vaccinations. It is currently recommended that all ferrets be vaccinated against two deadly and life-threatening diseases: canine distemper and rabies. The vaccine products available are specific for ferrets and have undergone extensive laboratory testing to determine that they are effective in preventing both diseases. Unfortunately, some ferrets may have adverse reactions to either vaccine.

Canine Distemper

Distemper is caused by a virus, and affects dogs, ferrets, raccoons and a number of other species. In ferrets, distemper causes a variety of symptoms, usually starting with fever, appetite loss, clear nasal discharge and a rash on the chin. The virus progresses and infected ferrets typically develop severe eye inflammation (conjunctivitis), and dermatitis with red blotchy skin and thickened footpads. Within several weeks the virus causes inflammation of the nervous system resulting in incoordination, convulsions, coma and death. Unfortunately, ferrets with canine distemper almost always die of the disease. Ferrets can acquire canine distemper from other animals sick with the disease. Since the virus can live for a short time in the environment or on clothing, ferret owners can potentially pick up virus from infected animals and bring it home to their ferrets. Once exposed, unvaccinated ferrets typically begin showing signs of the disease within 7-10 days. Ferrets vaccinated against canine distemper with an approved vaccine are usually well protected against the virus.

Rabies

Rabies is also caused by a virus, and is transmitted to ferrets through the bite of an infected animal. Rabies in ferrets is rare, as most ferrets are kept indoors where exposure to rabid animals is uncommon. However, accidental exposure may occur, and given that rabies is a serious cause of human illness and death, it is highly recommended that ferrets be protected against the virus. In fact, many communities require rabies vaccination of pet ferrets, along with dogs and cats. If an unvaccinated ferret bites a human, the health department is called in to make a determination of likely rabies involvement and in some cases may require that the ferret be killed and tested for rabies.

Vaccine Reactions

Vaccination is the process of injecting a small amount of killed or inactivated virus into the animal in order to stimulate the immune system. The resulting immune response can provide protection if some point in the future the animal is exposed to the live virus. Since vaccination involves the injection of a foreign substance into the animal (killed or inactivated virus plus carrier substances), the possibility of a strong immune system overreaction exists, resulting in a vaccine reaction.

Vaccine reactions typically occur within one to thirty minutes of vaccine administration.

The signs of vaccine reaction are variable. The ferret initially becomes depressed and quiet with a glassy-eyed appearance. Within a short period panting, quivering, vomiting and/or diarrhea, with eventual collapse may follow. Without appropriate therapy the signs may progress to seizures, coma and death.

Figure 1

Vaccine reactions are not uncommon in ferrets. The Drs. at Pet Care Veterinary Hospital give all ferrets Benadryl prior to vaccine and ask that you wait in our office for 15 minutes post-vaccination in case a reaction occurs. A ferret with a vaccine reaction will become suddenly very quiet (figure 1) and may soon have bloody diarrhea ((figure 2). This needs to be treated immediately!

Figure 2

Treating/preventing vaccine reactions

Many veterinarians pre-medicate ferrets with an injection of diphenhydramine (Benadryl®) just prior to vaccination in order to prevent or lessen the symptoms associated with a reaction. Your veterinarian may also recommend that you remain in the veterinary clinic for a 15-30 minute post-vaccination observation period. This will ensure that in the event of a vaccine reaction, your ferret will receive prompt medical attention. Treatment involves fluid therapy and various medications to help restore blood pressure, combat shock and control symptoms.

It is uncertain why some ferrets react adversely to vaccination. Vaccine products for any species, including humans, may cause reactions in a small number of those receiving the vaccine. The majority of vaccinated ferrets do not react unfavorably. Therefore, it is highly recommended that all ferrets receive annual vaccinations to prevent these two deadly diseases, despite the potentially small risk of a vaccine reaction.