[Source: European Centre for Disease Prevention and Control (ECDC), full PDF document: (LINK). Edited.]
COMMUNICABLE DISEASE THREATS REPORT - Week 4, 20-26 January 2013
Influenza A(H5N1) - Multistate (world) - Monitoring human cases
Opening date: 15 June 2005 - Latest update: 12 December 2012
The influenza A(H5N1) virus, commonly known as bird flu, is fatal in about 60% of human infections, and sporadic cases continue to be reported, usually after contact with sick or dead poultry from certain Asian and African countries. No human cases have been reported from Europe.
Update of the week
Since the last update on 17 December 2012, three new laboratory-confirmed human cases with influenza A(H5N1) virus infection, including two fatalities, were reported to WHO. All three patients were from Cambodia.
On 25 January 2013, the Cambodian Ministry of Health published a press release jointly with the Cambodia WHO country office announcing three new human cases of avian influenza A(H5N1). Two of the patients a 15-year old girl and a 35 year old man died. The third patient, an 8 months old baby, has recovered. The three patients come from three different provinces in Cambodia. All three had contact with poultry prior to their onset of illness. Since the last update on 17 December there have been poultry outbreaks in Indonesia attributed to influenza virus A(H5N1) clade 18.104.22.168. This clade has not been previously detected in Indonesia, although it has been circulating for some years in poultry and has been isolated from a few human cases with H5N1 infection in other countries.
Hong Kong reported the world's first recorded major outbreak of bird flu among humans in 1997, when six people died. Most human infections are the result of direct contact with infected birds, and countries with large poultry populations in close contact with humans are considered to be most at risk of bird flu outbreaks. ECDC follows the worldwide A(H5N1) situation through epidemic intelligence activities in order to identify significant changes in the epidemiology of the virus. ECDC re-assesses the potential of a changing risk for A(H5N1) to humans on a regular basis. There are currently no indications that from a human health perspective there is any significant change in the epidemiology associated with any clade or strain of the A (H5N1) virus.
This assessment is based on the absence of sustained human-to-human transmission, and on the observation that there is no apparent change in the size of clusters or reports of chains of infection. However, vigilance for avian influenza in domestic poultry and wild birds in Europe remains important.
WHO is now rreporting H5N1 cases on a monthly basis. ECDC will continue monthly reporting in the CDTR to coincide with WHO reporting.