|H3N2 canine influenza in Los Angeles County, 2017
- Please report cases of
Download our H3N2 Canine
Influenza handout -
In March 2017, H3N2 canine influenza was
identified in dogs in Los Angeles (LA) County. Most of the
dogs were imported from Asia and seen by a veterinarian
arrival into LA County. The dogs showed signs consistent
with influenza such as coughing, sneezing, fever and nasal
discharge. A total of 27 dogs were sick with the disease and
treated with supportive care. Final testing of two dog
revealed a strain of canine influenza (H3N2) commonly found
in Asia, further testing is pending.
After investigation, a total of 35 sick
dogs were identified out of 50 exposed, including 5
cases confirmed by laboratory
testing (PCR) and 30 suspected. The sick dogs, plus an
additional 8 healthy but exposed dogs, were put under quarantine
or isolation in 16 locations around Los Angeles County. Two
sick dogs have died, however both animals were suffering
from other unrelated illnesses. As of April 21st, 2017 all
remaining dogs have recovered and are being released from
quarantine. Samples from several dogs have been submitted to
veterinary virologists in order to compare this virus to the
H3N2 canine influenza virus that caused a large
outbreak in the Chicago area in 2015.
H3N2 canine influenza usually causes mild
disease in dogs and on rare occasions can also infect cats.
This strain of canine influenza was first found in the US in
2015 when it emerged in Chicago and spread to other parts of the
country. Infected dogs start shedding the the virus 2 days
before the start of clinical signs, and for 21 days or
longer afterward. Transmission of influenza usually occurs
through contact with infected respiratory secretions
(e.g. coughing, sneezing) as well as from contamination of the
environment (e.g. bedding, floors, bowls, collars, leashes).
To date, there is no evidence that humans
can become sick with H3N2 canine influenza.
providing assistance during this outbreak by:
Enforcing quarantine of
all affected dogs to prevent spread of the
Alerting veterinarians in
LA County of the outbreak through the Animal
Health Alert Network (AHAN).
veterinarians and affected parties by
During the investigation of the original
influenza outbreak, the Veterinary Public Health Program
(VPH) identified a dog that tested positive for H3N2 canine
influenza in early March. This case originated in San
Bernardino County and it pre-dates the importation of the
sick dogs from Asia. VPH is working closely with the
facility housing this dog to investigate any further spread
of the virus. So far, no other animal that came in contact
with this dog has tested positive for H3N2 canine influenza.
Impact of this
While the H3N2 strain canine influenza
causes a mild disease, many dogs in Los Angeles County may
be susceptible to this virus because of lack of previous
immunity. As of now, the spread of H3N2 appears to be
controlled in locally, however an uncontrolled outbreak may
lead to thousand sick dogs. This can have a significant
impact in dogs awaiting adoption in animal shelters. One of
the most effective tools to reduce the number of dogs
sick with this disease is to vaccinate them against H3N2
If you think your pet has
influenza, keep it away from other animals
and contact your veterinarian.
Pets that frequently
interact with other dogs (e.g. dog park,
groomer) should be vaccinated against H3N2
To prevent spread of
disease, do not let a sick pet come in
contact with other animals or share its food
bowl, leash, toys or other supplies.
Wash your hands after
touching your pet.
Report any suspected case
of influenza in dogs or cats to VPH using
this reporting form.
If a case is suspected,
use proper isolation measures to prevent
infection via direct contact or fomites.
disinfection and biosecurity available
Canine Influenza - Los Angeles County Department of Public
Canine influenza (Dog Flu) - Centers for Disease Control and
Canine Influenza - American Veterinary Medical Association
Canine Influenza H3N2 Updates - Cornell University Animal
Health Diagnostic Center
Last updated: April 21, 2017