Korea added 14,168 new Covid-19 infections, including 220 cases from abroad, bringing the total caseload to 24,634,296, according to the Korea Disease Control and Prevention Agency (KDCA). The figure is the lowest since July 11, when the country reported 12,672 cases.

The nation also reported 33 more Covid-19 deaths, raising the death toll to 28,246. The fatality rate stood at 0.11 percent. The number of critically ill patients came to 427, up 11 from the previous day, the KDCA said.

Starting Monday, the government lifted all outdoor mask mandates.

The government had started implementing the mask-wearing rules in Oct. 2020. While it partially eased outdoor mask mandates in May 2022, it kept mandatory outdoor masks when participating in gatherings with more than 50 people.

However,  the government said it would maintain its rules for wearing indoor masks for the time being.

"While we cannot estimate the exact time and scale of the next wave, there is no guarantee that it will not happen," said Jung Ki-suck, head of the National Advisory Committee on Infectious Disease Crisis Response, during a press briefing on Monday. "In preparation, the duty to wear masks indoors needs to be maintained."

Jung also stressed that although the recent national antibody-positive rate survey showed that more than 90 percent of Koreans had antibodies for Covid-19, the actual immunity ability is different from possessing antibodies.

"During the Omicron pandemic earlier this year, about 23 million people, including hidden infection cases, were believed to have immunity toward Covid-19," Jung said. "However, we saw a summer resurge happen a mere four months after the Omicron pandemic peaked in March."

Also, receiving Moderna's bivalent vaccine does not completely prevent the currently prevalent mutation BA.5, Jung added.

Jung stressed that just because a lot of citizens tested positive for the virus a few months ago doesn't mean there won't be a next viral wave.

"It is hopeful that there are many people with immunity, but no one can predict the timing and scale of the next viral wave," Jung said. "Therefore, we must prepare thoroughly for the wave."

The government will accept advance reservations for booster vaccinations using an improved bivalent vaccine that can also respond to the Omicron variant from Tuesday.

The improved vaccine is a vaccine developed to respond to both the initial Corona 19 virus and Omicron variant (BA.1). The government plans to use Moderna's bivalent vaccine for the booster shots.

Those aged 60 and over, with weakened immunity, and patients in long-term care hospitals and facilities are given priority in receiving the vaccine. Health authorities estimated that about 13 million people will be included in the priority group.

However, the government stressed that same-day vaccination using residual vaccines will be available for those not included in the priority group -- those in their 50s, with underlying diseases, and adults aged 18 to 49.

Health officials also stressed that they plan to quickly introduce Pfizer's BA.1-based bivalent vaccine. Officials recommended citizens receive the mRNA-based bivalent vaccine instead of the conventional vaccines targeting the original Covid-19 virus.

According to the KDCA, about 44.67 million among 52 million Koreans have been fully vaccinated. In addition, about 33.59 million people had received their first booster shots, and 7.41 million had their second booster shots.