Reporting from The Standard and RTHK says that animal health authorities in China acted under the country’s ASF contingency plan after six pigs at a farm site tested positive for the virus on 4 February. They culled 240 pigs who shared the same barn as the infected animals. Tests on pigs in other barns were negative.

"Given the fact that there is stringent biosecurity measures implemented on the farm to minimise the risk of infection, and that all sheds are separated structures without any linkage in between, further observation and testing are considered appropriate without the necessity of culling any pigs in other sheds at this stage after consulting international experts in the area," a department spokesman said.

"Thorough cleansing and disinfection is being conducted on the farm."

Authorities have also tested three other pig farms within a 3km radius of the first outbreak. No abnormalities or infections were detected. However, movement of pigs on nearby farms has been suspended and authorities are testing those animals.

Read more about this story in The Standard.