ภาพประกอบ: Volunteers from the Civil Aid Service (CAS) wearing protective clothing take part in a chicken cull demonstration as part of an emergency response exercise in Hong Kong on May 21, 2017. Some 1000 CAS members took part in a two-day exercise to test their deployment and search and rescue capabilities during an emergency. AFP

ภาพประกอบ: Staff wearing protective clothing cull chickens in a Sham Shui Po market after the deadly H5N1 bird flu virus was found in samples collected from the market’s poultry stalls in Hong Kong, on June 7, 2008. The government has ordered an immediate ban on all poultry imports from China. AFP PHOTO

ภาพประกอบ: Staffs cull chickens in a Sham Shui Po market after the deadly H5N1 bird flu virus was found in samples collected from the market. The Hong Kong’s government ordered an immediate ban on all poultry imports from China. AFP

ภาพประกอบ: Outbreaks of highly pathogenic H5N1 avian influenza in Maryland, Wisconsin and Missouri in the United States. Zuma Press/Alamy