On Tuesday, China joined a growing list of countries barring U.S. poultry imports after avian influenza was found in backyard chicken and guinea fowl flocks in Oregon and Washington. More than 30 countries have banned or restricted the import of poultry originating in one or both of those states. China and the 28 members of the EU joined Thailand, South Africa, Sri Lanka and the Republic of Korea in banning all poultry meat exported from the U.S. since December. The U.S. Department of Agriculture’s Food Safety and Inspection Service “has been informed by [the Animal and Plant Health Inspection Service, or APHIS] that until further notice, due to the finding of highly pathogenic avian influenza (HPAI) in a backyard flock in Oregon and Washington, the certification statement referring to the United States as free from HPAI cannot be endorsed,” the agency notes on its list of export requirements. “Health certificates with certification statements referring to HPAI freedom in a state, region, zone or area can be endorsed for all states except Oregon and Washington.” USDA has not found any cases of avian flu in any commercial poultry in the U.S. The virus has the potential to cause illness in humans, but no human illnesses worldwide have been reported in connection to the strains detected in the Pacific Northwest. APHIS says that the bans are to protect each country’s poultry populations, and that the agency also imposes import restrictions on poultry and poultry products from areas affected with HPAI in order to protect U.S. poultry. In Canada, an outbreak of avian flu in British Columbia has spread to several poultry farms and affected about 245,000 birds, according to the Associated Press, but appears to be under control. The World Organisation for Animal Health reports that strains of the H5 and H7 virus have been detected in animals in seven additional countries since December. Since the first of the year, a handful of human illnesses from avian flu have been reported in China and in Egypt, where two people, including a three-year-old child, subsequently died.