[Source: European Centre for Disease Prevention and Control (ECDC), full PDF document: (LINK). Edited.]
COMMUNICABLE DISEASE THREATS REPORT
Week 10, 3-9 March 2013
Influenza A(H5N1) - Multistate (world) - Monitoring human cases
Opening date: 15 June 2005 Latest update: 27 February 2013
The latest global WHO update on 15 February acknowledged seven new human cases with influenza A(H5N1) virus infection, including six fatal cases in Cambodia and two new human cases in China who remain in critical condition.
The Chinese cases come from the same province but they do not seem to be epidemiologically linked. Neither had documented contact with sick or dead poultry. These cases were included in last week's CDTR.
In addition, Egypt has reported one new fatal human case with influenza A(H5N1) virus infection in Behera Governorate in a female patient. An investigation found that she had been exposed to sick or dead poultry. This case had not been reported previously.
On 21 February 2013, WHO and the Ministry of Health of Cambodia reported in a joint press release another fatal case of influenza A(H5N1) virus in Cambodia. This case was a 20-month-old boy from Kampot province who was found positive for influenza H5N1 on 19 February 2013 by Institut Pasteur du Cambodge.
During the week leading to 28 February WHO in Cambodia confirmed a ninth case. This 35-year-old man from Kampong Cham province was confirmed positive for influenza A(H5N1) on 23 February by Institut Pasteur du Cambodge. He died on 25 February. He came into contact with sick poultry prior to becoming sick. This is the ninth case this year and the 30th person to become infected with the H5N1 virus in Cambodia. It is also the twenty-seventh fatal case in the country. Of the 30 confirmed cases, 20 were children under 14, and 19 of the 30 were female.
Globally since 2003, there have been 622 laboratory confirmed cases of avian influenza with 369 related deaths.
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 reporting H5N1 cases on a monthly basis. ECDC will continue monthly reporting in the CDTR to coincide with WHO reporting. The CDTR includes the A(H5N1) threat this week due to the new reported cases in Cambodia, China and Egypt.