Public Health England flu expert Professor Nick Phin said:
On 8 January 2014, Alberta health officials confirmed an isolated, fatal case of Influenza A (H5N1) or avian influenza, in a person who had returned from travel to Beijing, China. Canadian authorities are following up all contacts of the patient and are working with the Chinese and World Health Organization (WHO) on the case.
H5N1 has been circulating in poultry over the last decade and occasionally humans are infected. Infection of humans causes severe illness with a high death rate, but the virus does not transmit readily from person-to-person.
The overall public health risk assessment for avian influenza A (H5N1) viruses is that whenever influenza viruses are circulating in poultry, sporadic infections or small clusters of human cases are possible, especially in people exposed to infected household poultry or contaminated environments. However, this influenza A (H5N1) virus does not currently appear to transmit easily among people. As such, the risk of community-level spread of this virus remains low.
The UK is amongst the best prepared countries in the world when dealing with new threats such as avian influenza. Public Health England has arrangements in place that will be able to identify a new influenza virus, for the detection and investigation of suspected cases and the management of confirmed cases and their contacts.
H5N1 is an avian influenza virus. It was isolated from the first time from a human patient in Hong Kong in 1997. Since then there have been a number of outbreaks in poultry birds in Asia, Europe, Africa and the Middle East and there are sometimes human cases in those who have close contact with infected poultry.
From 2003 through to 20 December 2013, 648 laboratory-confirmed human cases of avian influenza A (H5N1) virus infection have been officially reported to WHO from 15 countries, primarily among people who have had contact with infected birds. Of these cases, 384 died. It has been found in birds in Asia, Europe, Africa and the Middle East. It causes severe illness in humans and kills about 60% of those who are infected.
H5N1 causes severe illness in poultry and transmits rapidly from one bird to another within an affected flock. The virus does, on rare occasions, transmit to humans who have close contact with infected poultry, but being an avian virus does not have the ability to transmit readily from person-to-person.
According to WHO, H5N1 avian influenza virus remains one of the influenza viruses with pandemic potential, because it continues to circulate widely in some poultry populations, most humans are likely to have no immunity to it, and it can cause severe disease and death in humans.