Thailand recorded 14 new cases of the novel coronavirus on Sunday, including two local transmissions in Bangkok, for a total of 4,086. No new deaths were reported.
The Centre for Covid-19 Situation Administration (CCSA) said one of the two local transmissions is a 26-year-old woman who went to Tachileik on Nov 6.
The CCSA did not say why the woman was regarded as a local transmission case despite having returned from Tachileik. However, CCSA records show that she sneaked back across the border on Nov 27 with a male friend. The two stayed together at a hotel in Mae Sai district of Chiang Rai, opposite the Myanmar town. They also visited several places in Mae Sai together.
The woman flew from Chiang Rai to Bangkok on Nov 29 on THAI Smile flight WE137, and stayed at a hotel in the capital until Thursday.
The man left Chiang Rai for Bangkok a day later, on Nov 30.
On Friday, the two went to the Hospital for Tropical Diseases in Bangkok, where the man tested positive for Covid-19. The woman reportedly felt ill that day, with a runny nose, and returned to the hospital on Saturday -- when she also tested positive for Covid-19.
Sophon Iamsirithaworn, director of the general communicable disease division, said five people – mostly in Chiang Rai -- were at high risk of contracting the disease due to close contact with her. One of them was tested in Chiang Rai and the result was negative, he added.
The second case of local transmission was a female health worker at an alternative state quarantine facility at a private hospital. She had a fever on Thursday and a test on the same day was positive.
In addition to the two local cases, the centre recorded another 12 imported cases on Sunday -- two of them Thais who illegally crossed the border back from Myanmar. Another eight cases were foreigners who flew in from abroad.
The CCSA said one of the two Thai patients was a 70-year-old man who travelled to Tachileik and then illegally entered the country in Mae Sot district of Tak on Nov 29. His test at Mae Sot Hospital on Friday was positive.
Another case was a woman 26, who crossed from Myanmar to Mae Sot on Nov 27. She worked at an entertainment venue in Tachileik, the centre said, without elaborating.
The CCSA did not explain why two Thais working in Tachileik illegally returned to the country by crossing the border between Myawaddy and Mae Sot.
Myawaddy is located about 600 kilometres southwest of Tachileik.
Authorities have tightened security along the Thai-Myanmar border in Mae Sai since a Thai woman tested positive in Chiang Mai after sneaking back across the border on Nov 24. She had been working at 1G1 Hotel, a suspected Covid hotspot in the Myanmar town.
Since the first case was reported on Nov 24, Thailand has now found 23 patients who were infected with the coronavirus in Tachileik or caught it from people who returned from there.
CCSA spokesman Dr Taweesilp Visanuyothin urged all Thais illegally returning from Myanmar to report to health officials for testing to prevent the virus from spreading.
"We do not know how many more cases will be found. Please report to us and we will take care of you," he added.
The latest cases brought the accumulated tally in Thailand since the start of the outbreakto 4,086.