Avian influenza is a type of influenza A virus which is also known as “bird flu”. Avian influenza is found in wild birds, and can also infect domestic poultry, such as chickens and turkeys. It is rare for people to become infected with avian influenza. If people do become infected, it is usually because they have had close contact with infected poultry or their environment. Close contact could involve working with infected poultry, having infected poultry in the backyard or house, touching infected poultry, their feces or bedding, or being in areas where infected poultry have recently been. Avian influenza does not spread easily from person to person. In rare situations when avian influenza has spread from one person to another, it has occurred with close contact, such as to a caregiver from a family member who is sick with avian influenza.
Avian influenza viruses can be “low pathogenic”, meaning that they cause little to no illness in infected domestic birds, or “highly pathogenic”, meaning that they can cause severe illness or death in infected domestic birds. This terminology relates only to how the virus behaves in domestic birds and not to how it behaves in humans.
In December 2014, a new strain of avian influenza A (H5N2) was identified in commercial poultry in British Columbia. Since then, H5N2 has been identified in commercial poultry, backyard flocks and wild birds in several states in the United States. H5N2 is a highly pathogenic type of avian influenza virus, which means that it is detected in a flock of birds because the birds become sick and die. It is believed to be spread by migratory wild birds that may not have any symptoms of the infection. To date, there have been no human infections caused by the H5N2 strain. The avian influenza outbreak that began in Oxford County, Ontario in early April 2015 has been confirmed as H5N2.
Currently, no human cases of infection with the H5N2 strain have been reported and so the risk to the public from H5N2 avian influenza is very low. Infrequently, other types of avian influenza viruses have infected humans, causing mild to severe respiratory illness. Symptoms of an avian influenza infection can include fever, body aches, cough, sore throat, red eyes, breathing problems and sometimes, diarrhea and vomiting.
In the unusual event that people are infected with avian influenza, infection typically occurs after close contact with birds that are infected with the virus, or contact with their environment (e.g. feces, bedding, contaminated feed or water). Domestic birds that are infected with highly pathogenic avian influenza strains will be sick or dead. If a person does become infected, it is very rare for them to transmit the virus to someone else.
Because of early detection and control of birds infected with highly pathogenic avian influenza, the chance of infected birds entering the food chain is very low. Properly handled and cooked poultry (e.g. chicken, turkey, duck) does not pose a risk for avian influenza infection. Below are the recommended minimum internal cooking temperatures that must be reached to ensure that the product is safe to eat. Use a food thermometer to ensure food has reached the proper temperature.
As well, eggs should be thoroughly cooked prior to consumption.
When infected domestic flocks are identified, the birds are humanely euthanized and only essential workers are allowed to enter the barn or area where the birds live. Nearby poultry farms are quarantined, which means that movement in and out of the farms is controlled to prevent the virus from spreading. Birds on quarantined farms are also monitored for illness. The Canadian Food Inspection Agency implements and monitors quarantines of this type.
People who have had contact with birds that are infected with avian influenza are monitored for 10 days to ensure that they don’t become sick. The local public health unit will assist with this monitoring. Sometimes, influenza antiviral medication may be recommended to help prevent infection, particularly when there has been a lot of contact with infected birds or their environment.