The 12 are under close observation after they came into contact with a confirmed monkeypox patient who had taken a transit flight from Thailand, the Public Health Ministry said on Monday.
The passenger was in Bangkok for two hours before he caught a flight to Australia, where he was confirmed to have monkeypox.
The DDC said on Thursday that there was no confirmed case of monkeypox in Thailand so far.
Dr Chakkarat Pitayawonganon, director of the department's epidemiology division, said that the situation is not worrying because they are low-risk contacts. He added that they will be monitored for 21 days.
He explained that monkeypox is a disease needing observation; it was not a dangerous communicable disease. People who were infected could treat themselves. However, patients should see a doctor immediately when they have symptoms.
Chakkarat said the department would monitor the situation to decide if they should distribute monkeypox vaccines to medical personnel. If the disease spreads, vaccines must be distributed to prevent more people from being infected.
However, if the disease does not spread, side-effects from vaccines might be more severe than being unvaccinated, Chakkarat said.
If vaccines need to be given, they will be made available first to risk groups, such as people who have come from foreign countries or medical personnel.
Moreover, they will have to decide which group of medical personnel should get the vaccines because there are a great number of medical personnel, he said.