COMMUNICABLE DISEASE THREATS REPORT
Week 7, 10-16 February 2013 / CDTR
Influenza A(H5N1) - Multistate (world) - Monitoring human cases
Opening date: 15 June 2005 Latest update: 8 February 2013
On 25 January 2013, WHO reported three confirmed cases of A(H5N1) virus infections in Cambodia. Two of them, a 15-year old girl and a 35 year old man, died. The third patient, an eight month old baby, has recovered.
The three patients came from three different provinces in Cambodia. All three had contact with poultry prior to their onset of illness.
On 29 January 2013, the Cambodian Ministry of Health published a joint press release with WHO confirming that two more cases have tested positive for the A(H5N1) virus. These are the fourth and fifth confirmed cases of avian influenza in Cambodia so far this year. Both the fourth case, a 17-month-old girl from Kampong Speu province and the fifth case, a nine year old girl from Kampot Province, died. In both cases, there is evidence of recent deaths among poultry in the village.
On 8 February 2013, the Cambodian Health Ministry and the WHO published a joint press release confirming a death of a five year old girl of avian influenza H5N1.
On 13 February 2013, the Cambodian Health Ministry and WHO published a joint press release confirming a seventh case of H5N1. The case is a three-year-old girl from Kampot province. She was found positive for H5N1 influenza on 11 February 2013 and died on 13 February 2013. There is evidence of recent deaths among poultry in the village and the girl had a history of coming into contact with poultry prior to becoming sick. In 2013 there have been seven H5N1 cases in Cambodia, of which six cases died.
Since 2005, there have been twenty eight cases of H5N1 in Cambodia including 25 fatalities. Out of the twenty eight confirmed cases, nineteen were children aged under 14 years and nineteen occurred in females.
The Hong Kong Centre for Health Protection (CHP) of the Department of Health received notification from the Ministry of Health on 10 February concerning two confirmed human cases of influenza A (H5N1) in Guizhou.
According to the CHP spokesman the patients were a 21-year-old woman and a 31-year-old man living in Guizhou. Both patients did not report obvious exposure history to poultry before the onset of symptoms. There is no epidemiological link between these two cases. Media reported on 13 February that the woman died of multiple organ failure.
Globally since 2003, there have been 619 laboratory confirmed cases of avian influenza with 366 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 and China.