 Tweet (NewsTarget) The bird flu has struck South Korea after three years of little to no activity. The H5N1 virus is a highly virulent strain that could potentially spread to and kill humans. South Korea's Agriculture Ministry said earlier this week it suspected bird flu had killed 6,000 chickens at a farm in the southwest of the country that lies on a path for migratory birds. A Ministry official said 'It is the H5N1 strain' after seeing test results from the suspected case. After the results were reported, the Agriculture Ministry ordered the culling of 236,000 poultry within a 1,640-foot radius of the farm in South Korea's North Cholla province, which is located about 100 miles from Seoul. In addition, quarantine authorities also banned the shipment of more than 5 million poultry from 221 farms within a 6.2-mile radius of the farm. No signs of human infection had been spotted or reported among local residents or quarantine officials, according to another Agriculture Ministry official. Between December 2003 and March 2004 -- about 400,000 poultry at South Korean farms were infected by bird flu. That recent history has caused concern on this latest case, because during the outbreak from 2003, South Korea culled 5.3 million birds -- and spent about $1.6 billion on preventing the disease from spreading. After the 2003 South Korean outbreak, tests in the U.S. indicated that at least nine South Korean workers involved in the cull had been infected with the H5N1 virus. However, none of the infected workers developed major illnesses. Since 2003, outbreaks have been confirmed in around 50 countries and territories around the globe. The World Health Organization said that by Nov. 13 of this year, there had been 258 cases of human infection of the H5N1 strain since 2003, resulting in 153 deaths. Many of the H5N1 victims were in Asia, with 98 deaths in Vietnam and Indonesia. ### 