[Since this report, one human case in China has died. The common thread is everyone "does not seem" to e epidemiologically related, and "additional human cases might be expected"...]
Summary and assessment as of 15 February 2013
Human infection with avian influenza A(H5N1) viruses and associated animal health events
From 2003 through 15 February 2013, 620 laboratory-confirmed human cases with avian influenza A(H5N1) virus infection have been officially reported to WHO from 15 countries, of which 367 died.
Since the last update on 16 January 2013, ten new laboratory-confirmed human cases with influenza A(H5N1) virus infection were reported to WHO.
Since 16 January, Cambodia reported seven new human cases with influenza A(H5N1) virus infection including six fatal cases. These cases come from four provinces all located in southern Cambodia. These cases do not seem to be linked epidemiologically, and most had contact with sick poultry in the village. Enhanced surveillance has been put in place and did not detect additional cases linked to these cases. Current evidence does not support human-to-human transmission. It has been suggested that the A(H5N1) virus is endemic in poultry in Cambodia(1), and that there is more poultry and human movement around the Lunar New Year. As such, additional sporadic human cases might be expected.
Egypt has reported one new human case with influenza A(H5N1) virus infection in Behera Governorate. The A(H5N1) virus is also endemic in poultry in some areas of Egypt, and additional sporadic human cases are possible.
On 10 February 2013, China reported 2 new human cases of influenza A(H5N1) virus infection. Both remain in critical condition. The cases come from the same province but do not seem to be epidemiologically linked. Neither had documented contact with sick or dead poultry. Contact tracing and follow up is on-going but no additional cases have been identified. The last official report of A(H5N1) in poultry in mainland China was from Guangdong Province in September 2012.
(1) Sorn, S., et al. Dynamic of H5N1 virus in Cambodia and emergence of a
novel endemic sub-clade. Infect. Genet. Evol. (2012), http://dx.doi.org/10.1016/j.meegid.2012.05.013 http://www.sciencedirect.com/science/article/pii/S1567134812002158