Upper respiratory infections are common in both young and mature ferrets, depending on their association with other animals and people, and the quality of their environment. Some human cold viruses are infectious for ferrets, as is human influenza. Early research on human influenza used ferrets as models of the disease.
Baby ferrets are more susceptible to respiratory disease when they are stressed by a combination of weaning, overcrowding, and poor housing. Many kits are shipped by air, exposing them, and the humans who travel by plane, to a great variety of respiratory viruses. They may also be exposed to influenza and cold viruses when sold to pet shops, taken to shows, or adopted by new owners.
At pet shops, the ventilation and room temperature might not be ideal. Most other pet shop residents need a warmer environment than ferrets. Except in major pet shops, where there are separate rooms with individual ventilation and heating systems for different types of animals, the ferrets are too warm.
Ferrets that go to shows are exposed to human and ferret viruses while subjected to extra stress, and less than ideal ventilation, depending on what type of building is housing the show.
Upper respiratory infections
Most ferrets with respiratory diseases are no sicker than a human child with a cold. A ferret with a flu or cold will be noticed sneezing, and if you look closely, you will see a slight nasal discharge, like a wet moustache near the nostrils. Sneezing and runny noses are rarely caused by allergies in ferrets, although some ferrets are irritated by dusty clay litter. Either influenza or cold viruses usually cause a less severe disease in ferrets than in people. However, bacterial infections may be superimposed on the original disease in stressed animals, and these may require veterinary treatment.
Most ferrets with an upper respiratory infection, like most people, will be much better in a couple of days. If not, the ferret should be taken to a veterinarian, who may prescribe antibiotics. It is difficult to give pills to ferrets, but they cooperate very well when treated with sweet-flavored pediatric antibiotic suspensions. They usually need treatment for 5 to 7 days.
Ferrets with upper respiratory infections (colds) cannot breathe well through their noses and often eat poorly. They can't smell the food and it's hard to swallow with blocked nostrils. The ferret's nose must first be cleaned so that he can breathe. Then add water to his favorite pellets, microwave for 10-15 seconds to soften the food, stir it well, and give it to the ferret warm. Heating makes the odor stronger and the softer texture is often accepted by sick ferrets. Mixing with chicken broth instead of water also increases palatability.
Ferrets boarded at veterinary hospitals or at animal boarding facilities may be infected with Bordetella bronchiseptica, which is a cause of kennel cough in dogs and sometimes cats. This bacterial disease can make stressed ferrets very sick, causing a thick yellowish nasal discharge that blocks the nostrils. If untreated, some develop pneumonia that responds poorly to antibiotics. Occasionally, the bacteria produce a toxin that causes convulsions and coma.
The best way to avoid Bordetella bronchiseptica infection is either not to board the ferret where there are dogs, or have it vaccinated before it enters the kennel. There is a killed, injectable Bordetella bacterin intended for dogs that works well in ferrets. It must be given at least 10 days before exposure to infection to have its greatest effect, and the ferret should have a booster the day it enters the kennel.
There is also an intranasal vaccine for dogs that contains live bacteria and canine parainfluenza virus. This vaccine may induce respiratory disease in ferrets and is NOT recommended for them.
Some boarding kennels house ferrets in the same area as cats, which less frequently carry Bordetella. It is still wise to have the ferret vaccinated when boarded, because the bacteria are airborne and can be carried on people's hands.