Update on Human infection with avian influenza A(H5N1) viruses

From 2003 through 31 December 2013, 648 laboratory-confirmed human cases of avian influenza A(H5N1) virus infection have been officially reported to WHO from 15 countries. Of these cases, 384 died.

H5N1 viruses are considered endemic in poultry in at least six countries (alphabetically: Bangladesh, China, Egypt, India, Indonesia and Vietnam) with sporadic detection in wild birds and poultry outbreaks occurring in other countries. The virus also is circulating widely in other countries in those regions. 

The count of WHO-confirmed H5N1 human cases in 2013 is 38 in six countries Bangladesh (1 case), Cambodia (26), China (2), Egypt (4), Indonesia (3), and Vietnam (2). These same six countries were the only countries to report H5N1 cases in 2012.

For more information on H5N1 human cases in Cambodia during 2013, go to:

http://www.wpro.who.int/mediacentre/releases/2013/20131114/en/index.html

On 9 January 2014, WHO has been informed of the first ever human case of H5N1 i in Canada and the first confirmed human case in the Americas Region.

The patient is a previously healthy adult, who visited Beijing, China. He was symptomatic when travelling back to Canada with malaise and feeling feverish.

The person had no known exposure to poultry or other animals, nor to ill individuals.

Close contacts, including household contacts and health care workers, are under observation and have received antiviral post-exposure prophylaxis. All contacts have been asymptomatic to date. Follow-up of the airline passengers is also ongoing.

Overall public health risk assessment for avian influenza A(H5N1) viruses: 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.