The three other women were found to be infected after they sneaking back into the northern province last week. Two remained in Chiang Rai and one travelled to Chiang Mai, sparking fears of an outbreak in the North.
The fourth case reportedly worked with the three other women in the entertainment industry in Myanmar’s Tachileik city, before sneaking back over the border to escape Covid-19 restrictions there.
The infected woman quarantined herself at a Chiang Rai hotel, before developing symptoms and surrendering to public health officials.
Sanitisation operations have begun at public venues in Mae Sai district, including the market.