Korea is seeing COVID-19 patients requiring critical care at levels last seen during the surge in the winter, with cities running out of beds to accommodate them.

The number of critically sick patients reached 403 on Saturday, the highest since the string of nursing home outbreaks in January, exhausting hospitals across Korea. No critical care beds were left in Daejeon by Saturday’s end, with only about 30 percent remaining nationwide.

COVID-19 projections by the National Institute for Mathematical Sciences and the Korean Mathematical Society published Friday showed severely or critically sick patients could number more than 700 in four weeks’ time if the restrictions in place fail to contain the surge.

Beginning Monday, the nightly curfew for eateries begins at 9 p.m. instead of 10 p.m., in the wider Seoul area. The ban on social gatherings of two or more after 6 p.m. remains in effect until Sept. 5.

People who are fully vaccinated face more lenient rules. Fourteen days after the one-dose Johnson & Johnson vaccine or the second dose in the two-dose series of other vaccines, people can gather in groups up to four.

Over the weekend, 20 patients died from COVID-19. So far in August, five patients in their 20s have died, all of whom had existing medical conditions. The only two medical conditions that qualify one for priority vaccinations in Korea are chronic obstructive pulmonary disease and chronic kidney disease.

Korea’s vaccine drive has accelerated this month, with an average of 239,838 doses being administered each day. The average in July was 90,335 doses daily.

People under 50 can get their first dose of either Pfizer of Moderna vaccines beginning Thursday, and they are now eligible to receive AstraZeneca’s vaccine if they wish. About 60 percent of people aged 18-49 have booked an appointment as of Saturday.

Nearly six months into the vaccination program, slightly more than half of 51 million people in Korea have received at least a single dose of a vaccine to date, while 22 percent have been fully vaccinated.

In the next two weeks, 7 million doses of Moderna’s vaccine are due to arrive in Korea, according to the government on Sunday, with 450,000 more doses of the same vaccine to be supplied by the Romanian government. On Sunday, a combined 11 million doses of AstraZeneca, Pfizer, Moderna and Johnson & Johnson vaccines remained in Korea.

After supplies are restored, the government said the administration interval between two Pfizer and Moderna doses may be readjusted to the standard three to four weeks from the current six weeks.

Korea aims to vaccinate 70 percent of the population with at least one shot before Chuseok, the national holiday falling Sept. 18-22.

Korea posted 1,418 more cases in the 24 hours ending on Sunday at midnight out of 81,737 tests conducted. In the past week, the number of cases confirmed each day has averaged 1,758, with the cumulative total reaching 237,782 as of the latest count.

By Kim Arin (arin@heraldcorp.com)