[Preventive Responses to Avian Influenza Infection in Human in the Republic of Korea, 2021-2022]

Avian influenza (AI) in humans is an acute respiratory infection caused by direct exposure to birds infected with AI viruses, such as H5N1, H7N7, and H7N9, or to contaminated environments. During 2021-2022, although no domestic AI cases in humans were confirmed, 47 cases of the highly pathogenic AI virus H5N1 were detected in poultry from seven cities or provinces nationwide. Furthermore, 148 cases were detected from samples of wild bird feces and carcasses from 12 cities or provinces and 48 cities or counties. When a highly pathogenic AI virus epidemic is expected in birds such as poultry, the Korea Disease Control and Prevention Agency (KDCA) establishes a cooperative system between local governments and related organizations to prevent the occurrence and spread of AI in humans. This is done by forming a countermeasure group and a surveillance system through preventive measures and on-site inspections. The surveillance system was particularly strengthened for farm workers or slaughter personnel, who are considered high-risk groups for AI, and preventive measures of seasonal influenza vaccination and antiviral drug administration were implemented. On-site inspections were conducted for slaughter personnel, who were instructed to wear personal protective equipment, and to classify the protected areas within the site. During the 2021-2022 season, 4,062 people (including farm workers, culling personnel, and hunters), in whom the highly pathogenic AI virus H5N1 was detected, were classified as a high-risk group for AI and managed accordingly. Although one patient was suspected of having AI, the test result was negative. No cases of AI in humans were reported. By describing the response process adopted by and results of the KDCA for the prevention of domestic AI in humans in 2021-2022, this report aims to provide a basis for establishing policies that are more effective in the prevention and management of AI in humans in the future.