Vivien010

This map shows the geographic distribution of  human H7N9 cases by second level administrative divisions (generally prefecture-level cities) in the People’s Republic of China and Taiwan from the period of November 1, 2013 to February 3, 2014.  The map is based on geolocational information for more than 150 confirmed and reported cases since November 1, 2013.  H7N9 cases from the 2012-2013 flu season are not included on this map.  Geolocational information for individual cases is derived from numerous online reports.

The map shows the frequency range of human H7N9 cases by second level administrative divisions (generally prefecture-level cities) in the People’s Republic of China and Taiwan through January 17, 2014. The map is based on geolocational information for more than 190 confirmed and probable cases. Geolocational information for individual cases is derived from numerous online reports and believe to be relatively accurate.

 Influenza A(H7N9) is a novel infectious bird flu strain that burst on the world's stage at the beginning of April 2013. Since then at least 132 individuals have been infected and more than 35 have died. [1]

In an article entitled Taiwan faces challenges on the emerging avian influenza A (H7N9) virus in China [2], researchers from Taiwan raise concerns over this novel influenza virus because it is a low path avian influenza virus (LPAI) in birds. This means that it does not kill off its avian hosts and is more difficult to detect in domesticated poultry and wild birds. The researchers note that after the closing the live poultry markets in Shanghai on April 5, the number of human cases caused by A(H7N9) virus dramatically decreased in that province. They speculate that A(H7N9) virus may spread silently in poultry in China and eventually spread globally through the migration of wild birds. They include a graphic depicting the geographic relation of humans cases in eastern portion of the People's Republic of China with the East Asian–Australasian migratory bird flyway.












The researchers in Taiwan have a right to be concerned. The only confirmed case of influenza A(H7N9) outside the mainland of the People's Republic of China was a Taiwanese national who worked in Suzhou, Jiangsu, where he was infected before returning to Taiwan.


[1] http://www.who.int/influenza/human_animal_interface/influenza_h7n9/RiskAssessment_H7N9_07Jun13.pdf



[2] http://www.jfma-online.com/article/S0929-6646%2813%2900171-X/fulltext