Facts About Avian (Bird) Influ
Avian influenza is a viral infection that can affect all species of birds. Some other mammals can also be infected with avian influenza such as pigs and humans. It is caused by type A strains of the influenza virus.Avian Influenza A (H5N1)
- There are many different subtypes of type A influenza viruses, one of which is H5N1.
- H5N1 is of particular concern because:
- The virus mutates rapidly
- It can cause severe disease in humans
- Is likely to acquire genes from viruses infecting other species
- The continued spread of infection in birds increases the opportunities for direct infection
of humans
The Development of Avian Influenza
- The first documented infection of humans with avian influenza virus occurred in Hong Kong in 1997, when the H5N1 strain caused severe respiratory disease.
- This marked the first time that an avian influenza virus was transmitted directly to humans and caused severe illness with high mortality.
- Alarm mounted again in February 2003, when an outbreak of H5N1 avian influenza was identified in Hong Kong.
- Avian flu is now endemic in the poultry population of many South East Asian countries
- Tests have confirmed the presence of H5N1 virus in human cases of severe respiratory disease in the northern part of Vietnam, Cambodia, Japan and Thailand.
- To date the avian flu virus has not been very effectively transmitted from person to person.
- If more humans become infected over time, the likelihood also increases that humans, if infected with human and avian influenza strains at the same time, could serve as the “mixing vessel” for the emergence of a novel subtype with sufficient human genes to be easily transmitted from person to person. Such an event would mark the start of an influenza pandemic.
Protection against Avian Influenza A (H5N1)
- Currently there is no vaccine capable of protecting humans from infection with avian flu.
- The WHO has made available several candidate strains for use by vaccine manufacturers and institutions to produce a vaccine against Avian Influenza A (H5N1).
- Studies suggest that the antivirals approved for human influenza viruses may work in preventing bird flu infection in humans.
- During a pandemic the antiviral drugs are likely to play an important but limited role.
Latest Map of Avian Flu Cases
For more information:
www.health.gov.on.ca/english/providers/program/emu/emu_mn.html
Or call toll free:
Health Care Provider’s Hotline 1-866-212-2272
Printer Version