Canine Influenza

Canine Influenza

Canine Influenza is a virus (H3N8) discovered in 2004, that is now documented in 30 states and considered prevalent in Colorado, Florida, N.Y. and Pennsylvania. 'Dog Flu' is a general term that can refer to a multiple number of organisms that cause flu-like illness. Canine Influenza (CIV) is a highly contagious respiratory infection of dogs (not a human influenza virus) that was originally an equine (horse) influenza virus. The virus has spread to dogs and can spread between dogs. It is a unique virus and is now considered to be dog-specific. There is no evidence of transmission to people. It is not seasonal and infections can occur year round.

Clinical Syndromes

Mild Form – Soft, moist cough for 10 to 30 days

May have dry cough similar to 'Kennel Cough', caused by Bordetella brochiseptica / Parainfluenza complex

May have thick nasal discharge, often due to secondary bacterial infection

Severe Form – High fever (104 – 106 F)

Clinical signs of Pneumonia, such as increased respiratory rate and effort

Pneumonia may be due to secondary bacterial infection

*Some dogs with pneumonia may not cough

Risk

CIV is a newly emerging disease, therefore, almost all dogs, regardless of breed or age, are susceptible to infection and have no immunity. Virtually all dogs exposed to the virus will become infected and nearly 80% of dogs will show symptoms of disease. This means that some dogs may be infected and don't show symptoms, but are still contagious to other dogs. Fortunately, most dogs have the mild form and recover within 2 weeks. Some dogs will progress to pneumonia, which is usually due to secondary bacterial infections. Fatal cases of pneumonia from CIV have been reported, but the fatality rate( 5-8%) has been low so far.

CIV is most likely spread in facilities where dogs are housed together and where there is high a turnover of dogs in and out of the facility, such as;

Shelters

Boarding / Training Facilities

Dog Day Care Centers

Veterinary Clinics

Pet Stores

Grooming Parlors

Dog Parks

Dogs that stay mostly at home and walk around the neighborhood are at low risk, provided there is not a high stray / loose dog population in the area.

CIV can be spread by 1) direct contact with respiratory secretions from an infected dog and aerosols generated by coughing and sneezing, 2) contact with contaminated objects, such as kennel surfaces, bowls and collars, and 3) people moving between infected and uninfected dogs (hands and clothing).

If your dog has signs of any respiratory disease, it should not participate in any activities or go to any facilities where other dogs may be exposed. Dogs may be contagious after symptoms have resolved, so keep your dog away from other dogs for an additional 1 – 2 weeks, just to be safe.

If your boarding / day care / groomer doesn't require proof of basic core vaccines, such as rabies, distemper, parvo and bordetella, you may want to reconsider your options. Any place where your pet has contact or will be kept in close quarters with other dogs should have the ability to do the following;

Require proof of basic core vaccines

Prevent sick animals from entering

Separate any animals that develop symptoms from others

Have good sanitation / infection control practices

The real concern now is trying to determine which pets are high risk and would benefit from a CIV vaccination. Not all pets qualify, at this time, and each pet should have it's own individual risk assessment. This is a new disease and the current practices will likely evolve over time.

Treatment

Since CIV is a viral infection, primary treatment is supportive care, such as fluids, while the virus runs it's course. Broad spectrum antibiotics may be prescribed, if a secondary bacterial infection is suspected. Dogs with pneumonia often require more intensive hospital care.

Diagnosis

CIV can not be diagnosed by clinical signs alone, because of all the other respiratory pathogens that cause similar signs of coughing, sneezing and nasal discharge.

If a dog has been sick for less than 4 days, a nasal or throat swab can be submitted to a validated diagnostic lab. Otherwise, blood samples taken during the first week and again 10 – 14 days later may identify antibodies in the serum, if the pet was never vaccinated.

Prevention

Routine infection control precautions are the key to preventing the spread of viral disease. CIV appears to be easily killed by disinfectants in common use in animal facilities. Places with high temperature and humidity (Florida) need to dry kennels and runs thoroughly after cleaning. Good precautions include routine and frequent hand washing, core vaccinations and avoidance of sick or potentially exposed pets.

If a dog with respiratory symptoms is identified : You should inquire if the pet was recently boarded / recently participated in dog – related group activities or was exposed to other dogs known to have CIV or Kennel Cough. This dog should be immediately separated from other dogs and be evaluated by a veterinarian. Isolation protocols should be rigorously applied for dogs showing signs of respiratory disease.

Vaccination

A vaccine for canine influenza was approved in May 2009. This vaccine contains inactivated whole virus, so the vaccine itself cannot cause respiratory symptoms. No side effects were noted in the first 700 dogs include in the field trial. The vaccine will aid in control of disease associated with CIV. The vaccine will not prevent infection. However, it will significantly reduce the severity and length of clinical illness, including reducing the incidence and severity of damage to the lungs. The vaccine also reduces the amount of virus shed or passed by a patient and decreases the length of time that virus is shed. (Dog is less contagious for a shorter period of time / gets less sick / gets better faster / less likely to have life-threatening complications)

This vaccine is based on a dog's lifestyle. It is not for all dogs at this time. Since it is more prevalent in Florida, some owners should consider this vaccine for their dogs. It is intended for dogs at risk for exposure, such as those participating in activities with other dogs or those housed in communal facilities (boarding, grooming, shelters). The facts that dogs can be contagious without showing symptoms and that dogs don't have any natural immunity is cause for concern, but not alarm. Procedures and protocols may change over time.

Marietta Animal Hospital Current CIV Policy

For additional information:

www.doginfluenza.com

www.avma.org

www.sheltermedicine.com

www.aspca.org

www.cdc.gov