Canine influenza is a highly contagious disease that can be rapidly transmitted through dog populations, particularly those in kennel or clinic environments, as well as other areas that bring multiple animals together in close settings. Do you need to consider having your pet vaccinated against canine flu? dr Andrea Perkins, clinical lecturer in infection control and biosecurity in the Auburn University College of Veterinary Medicine, weighs in with some advice.
What is canine influenza virus (CIV)?
Canine flu, or dog flu, is an illness caused by an infection with a type A influenza virus, two strains of which have been identified in dogs in the US: canine H3N8 influenza and canine H3N2 influenza. The virus is mainly transmitted through aerosols or droplets via cough, sneeze, bark or breath. The smaller, lighter droplets can be carried on air currents long distances, while the larger, heavier droplets land on surfaces in the surrounding environment. Depending on environmental conditions, influenza A viruses can remain viable on surfaces for 24-48 hours, but the good news is they are easy to kill with most common disinfectants. Direct contact with nasal discharges of infected dogs can also result in transmission.
Are all breeds of dogs affected?
The H3N8 strain initially caused outbreaks in racing greyhounds, but neither H3N8 nor H3N2 seem to show a propensity for any particular breed—all dogs are susceptible. Canine H3N2 influenza can also cause illness in cats.
How can you tell if your dog has CIV?
It usually takes about two to three days for a dog to show signs of illness following exposure. Infected dogs may exhibit a fever, cough, discharge from the eyes or nose, lethargy or decreased appetite. Exposure to canine influenza virus almost always results in infection. Approximately 80% of infected dogs will show visible signs of illness, but all infected dogs can spread the virus to other dogs regardless of whether they appear sick. Most infected dogs experience mild illness, but severe clinical signs such as pneumonia or secondary bacterial infections are possible and are more often associated with the H3N2 influenza subtype. Death occurs in less than 10% of dogs infected with canine influenza virus.
Is canine flu transmissible to people?
There have not been any canine influenza virus infections documented in people, but theoretically, zoonotic transmission could be possible. Historically, most notable influenza spillover events from animal hosts to people have arisen from swine or birds. From a public health standpoint, avoiding sick animals is generally recommended for young children, the elderly, or any individual with a compromised immune system.
What dogs are at increased risk?
Exposure to transient dog populations in kennels, shelters, rescues, dog parks or boarding, grooming or daycare facilities can increase risk of exposure. Cases of one or both canine influenza viruses have been reported in almost every state and can occur during any time of the year. Outbreaks arise sporadically, but with careful responses from veterinary and public health professionals, they usually subside within a few months.
There has been a recent outbreak in a Jefferson County, Alabama, shelter system and the surrounding community, but measures have been taken to contain the virus in the affected population. However, since there was some evidence of spread in the community, pet owners have been advised to avoid heavy dog traffic areas like dog parks.
Are vaccines available?
Yes, vaccines are available. A vaccine will not prevent transmission and subsequent infection from occurring, however, illness tends to be less severe in vaccinated dogs. Canine influenza virus is not widespread in the general dog population, yet certain activities or lifestyle conditions may increase risk of exposure. Your veterinarian can help you decide if a vaccination is right for your dog.
What should an owner do if they think their pet has canine flu?
Anytime you notice your dog is sick, a veterinary exam is a good idea. If you know or suspect your dog has been exposed to canine influenza virus, it is helpful to call your veterinarian ahead of time so they can take measures to prevent exposure of other patients in the clinic. They may ask you to wait in the car, use a separate entrance or special exam room, or they may wear protective clothing when handling your pet. This might seem a little scary, but it’s nothing to be alarmed about. Veterinarians often take extra precautions to protect people, animals and clinical environments from exposure to various germs. Additionally, avoiding contact with other dogs and practicing good personal and environmental hygiene will also help prevent further spread.
About dr Andrea Perkins:
dr Andrea Perkins is a clinical lecturer in infection control and biosecurity at Auburn University’s College of Veterinary Medicine. She has an undergraduate degree in animal science from the University of Minnesota, a Master of Public Health degree from the University of New England and a doctorate in veterinary science from Washington State University. Perkins, who is certified in public health under the National Board of Public Health Examiners, began her career in human hospitals before transitioning to veterinary hospitals, so she has a unique perspective on infection prevention at the human-animal-environment interface.