Wednesday's cases fall into two groups, one linked to earlier cases and the other mostly with overseas connections, Suwannachai Wattanayingcharoenchai, the director-general of the disease control department, told a news conference.
One group of 29 cases includes four from an entertainment venue and 13 from a crowded boxing match, both in the capital, Bangkok, while 12 came into contact with recorded patients, Suwannachai said.
A second group of six new cases includes one arrival from neighbouring Cambodia, he added.