The number of daily Covid-19 cases is likely to reach 5,000-10,000 during a new wave but numbers probably will drop quite quickly after that.
Dr Nitipatana Chierakul of Siriraj Hospital said the number of people infected with the Omicron XBB.1.16 sub-variant had increased but many patients had mild symptoms.
Severe health reactions that were reported were likely triggered by existing health conditions.
"When there is a new wave, daily cases are estimated to be between 5,000-10,000 patients. The number is relatively low compared to last year. Also, it is expected that cases will drop in a few weeks," he wrote.
Dr Nitipatana added that it is natural for the virus to spread during high-contact festivals like the Songkran celebrations.
Dr Nitipatana said most people have already developed immunity and booster shots should be given to people in vulnerable groups.
High-risk groups include seniors, people who have underlying conditions, children aged 6 months and older, pregnant people and frontline health workers.
The Public Health Ministry on Wednesday announced it will provide both influenza and Covid-19 booster shots to people at the same time, starting on May 1.
