The country registered 2,328 more Covid-19 cases and 19 new fatalities during the previous 24 hours, the Public Health Ministry announced on Sunday morning, as the number of patients in serious condition remained high.
This compared with 2,508 new cases and 17 coronavirus-related fatalities reported on Saturday morning.
There were 2,325 local cases and three imported cases.
The figures compiled Saturday did not include 6,777 positive results from antigen tests, which would raise the total to 9,105.
On Saturday, 2,043 Covid-19 patients were discharged from hospitals after recovering from the coronavirus.
Since the pandemic started in early 2020, there have been 4,530,105 Covid-19 cases, including 2,306,670 cases this year, with 4,474,416 complete recoveries to date.
The accumulated death toll stood at 30,700 since the beginning of the pandemic, including 9,002 so far this year.
The highest number of Covid-related fatalities in a 24-hour period was 312 recorded on Aug 13, 2021. The highest number of cases was 28,379 on April 1, 2022.
Seriously ill patients
The number of patients being treated for lung inflammation was 678 as of Saturday, down three from the figures reported a day earlier, according to figures of the Department of Disease Control.
The country has seen the number of patients in critical condition steadily rise since June 6, when it registered 601 such cases.
Health authorities have been monitoring the number amid concern that it was possibly connected with two new Omicron subvariants, BA.4 and BA.5, which are easily transmissible.
The Centre for Medical Genomics (at Ramathibodi Hospital has predicted the two subvariants are likely to become dominant strains in Thailand next month.
The emergence of the cases linked with the two subvariants was a reason for the Centre for Covid-19 Situation Administration (CCSA) to defer a decision to downgrade the coronavirus to the status of an endemic disease from last Friday to this coming Friday.
As of Saturday, a total of 24,898 were receiving Covid-19 treatment, including 109,252 in hospitals, 296 of them dependent on ventilators.
The 24-hour period also saw 2,043 patients discharged from hospitals after recovering.
According to the CCSA, the 19 people who died were aged from 46 to 95 with the average age of 81. All were Thais.
Bangkok logged four new deaths, while one was occurred in the adjacent province of Samut Sakhon.
Other central plains provinces further from the capital had three deaths - in Chon Buri, Trat and Prachuap Khiri Khan.
The North reported four deaths in Lampang, Chiang Mai, Chiang Rai and Phitsanulok.
The Northeast saw five new fatalities: two in Loei and one each in Khon Kaen, Si Sa Ket and Nakhon Ratchasima.
The South had two deaths in Chumphon and Nakhon Si Thammarat.
Vaccinations continued to progress, with 140 million doses administered as of Saturday. The government said 81.9% of the population has now received at least one dose of the vaccine, 76.5% at least two shots and 42.8% at least one booster shot.
On Saturday alone, 103,749 vaccine doses were administered — 8,992 as a first shot, 21,834 as a second shot and 72,923 as a booster shot.