03 April 2014 - The Food and Agriculture Organization of the United Nations (FAO) urges people to stay alert for influenza A(H7N9), especially in light of the upcoming Qingming festival on 5 April 2014, which is celebrated in China and some of its neighbouring countries and will last approximately three days. The festival, which is a yearly family event for honouring ancestors, is predicted to correspond to an increase in the purchase, slaughter and consumption of poultry as people may travel back to their hometown to celebrate with their families.
Even if reports on influenza A(H7N9) have declined in recent world news, there is a need to remain cautious with the increased evidence that the H7N9 virus continues spreading in poultry in China. Furthermore human cases are still being reported, with over 30 percent of human infections having a fatal outcome. According to figures from the World Health Organization (WHO), in the second and currently ongoing wave of H7N9 there are already twice as many reported human cases as compared to the first wave, which lasted from February 2013 to June 2013.
Even though the traditional winter influenza season is now coming to an end and the number of reported human H7N9 cases is expected to continue declining, an overview of last year's sequence of events, when the H7N9 virus first emerged in China, shows that human infections continued to be reported even after the Qingming festival which is usually celebrated at the beginning of April. FAO and other United Nations agencies such as WHO consistently emphasize the importance of good biosecurity and hygiene practices to reduce risks to animal health and human health. These can be found in the latest publication on Addressing Avian Influenza: Risk Management Along the Food Chain which includes crucial information on measures to mitigate the spread of H7N9 in poultry, such as implementing routine live bird market rest days, regularly cleaning markets and reporting sick or dead animals to the local veterinary or public health services. Human exposure to zoonotic pathogens, including H7N9, can further be minimized by following good hygiene practices, from avoiding the slaughter of animals in non-dedicated professional areas (e.g. at home) to washing hands before and after preparing food and eating only well-cooked meat products.
Because the influenza A(H7N9) virus creates a 'silent' infection in birds, it is not possible to know whether a bird is sick or not unless it is tested for the virus by submitting samples to a laboratory. This is one of the reasons why the first official notification of the H7N9 virus being detected in a farm, rather than a live bird market, dates only very recently to 18 March 2014 in Zhuhai, China. Timely detection of the virus in poultry farms is further challenged by difficulties encountered when attempting trace back of the virus from positive live bird markets to the farms from which the infected birds might have been sourced. Such investigations are facilitated by implementing poultry traceability systems, including source and trader registration at market level.
Both WHO and FAO stress that human cases of infection with avian influenza H7N9 virus are expected to continue to be reported as long as the virus is circulating in birds. With the knowledge that influenza A(H7N9) is still circulating in poultry in China, continued vigilance and monitoring is therefore essential. In addition to live bird markets, farms in high-risk areas should be routinely investigated through risk-based surveillance and laboratory testing. Areas at highest risk of an H7N9 incursion are those that have live poultry trade links with, or directly border on, affected areas. The spread of the virus in poultry populations will be facilitated in areas where poultry density is high and trade networks are extensive. More information can be found in FAO’s H7N9 Risk Assessments issue number 1 and issue number 2.