Doctors have confirmed that Prime Minister Prayut Chan-o-cha did not contract the novel coronavirus after inspecting the screening of incoming passengers at Suvarnabhumi airport, said Public Health Minister Anutin Charnvirakul on Thursday.

However, Mr Anutin admitted Gen Prayut's health has been affected by his workload and following medical advice, the premier's planned visit to Bamrasnadura Infectious Diseases Institute has been cancelled.

Rumours circulated that Gen Prayut may have been infected by the virus after he took sick leave on Thursday -- one day after he inspected passenger screening procedures at Suvarnabhumi airport. Some of his schedule was reassigned to Mr Anutin and Deputy Defence Minister, Chaichan Changmongkol.

Chaiyaporn Suchatsoonthorn, from the Public Health Ministry, said Gen Prayut's condition is not related to the coronavirus as it takes about four days for symptoms to show.