He said there were 226 Omicron patients from December 27 to 28 but most were infected with the Delta variant.
Suphakit said 740 Omicron patients were mostly found in Bangkok (277), followed by Kalasin (121) and Roi Et (50).
Of these, 489 had travelled from foreign countries and 251 were infected in Thailand.
The Omicron variant has been found in 19 provinces.
Suphakit said that cloth masks, surgical masks or N95 masks cannot prevent Covid-19 if people fail to wear them properly.
Related News
Omicron spreading due to short-range virus aerosols that easily enter mouth, nose: Siriraj doctor
Covid-19 screening points set up at Bangkok bus terminal, main railway station
This week will be a severity indicator of Omicron outbreaks: lecturer
He recommended that cloth masks should be made from muslin fabric with many layers.
Suphakit also warned that infected people who don’t wear their masks properly and sneeze or cough could spread Omicron.
He added that the variant has been found in 108 countries, including all states of the United States.