This is official as was published in the royal gazette
https://www.bangkokpost.com/thailand/ge ... m-6-placesThe government has defined four countries and two territories as dangerous zones and restrictions may follow to prevent the outbreak of coronavirus.
The announcement, dated Monday and published in the Royal Gazette on Thursday, classified South Korea, China, Macao, Hong Kong, Italy and Iran as "dangerous communicable disease areas".
"Thais and foreigners who came from these places would have to go through self-quarantine for 14 days at home or in a hotel room, where they have to report themselves to the authorities every day or officials will come to check on them," Dr Rungrueng said.
This means that all arrivals from these places, including those that transit through them, will have to provide the authorities with their addresses and travel plans and be self-quarantined for 14 days.