Chuseok outbreak worries became a reality as the number of newly-confirmed COVID-19 cases reached a record high of 2,434 Thursday after millions were on the move during the three-day holiday earlier in the week.

According to the Korea Disease Control and Prevention Agency, the country on Friday reported 2,416 local infections and 18 imported cases from the previous day. By region, Seoul, Gyeonggi Province and Incheon had 1,747 cases or 72.3 percent of the total.

The new high number of daily infections broke the previous record of 2,221 from August 11.

Health authorities repeatedly warned of a possible surge in the number of daily virus cases due to people traveling throughout the country to visit their hometowns or go on a trip over the five-day weekend.

“Despite many experts predicting that the number of confirmed cases would increase if movement increased, it is deeply regretful that we could not prevent this situation,” Prime Minister Kim Boo-kyum said Friday in a meeting of the Central Disaster and Safety Countermeasures Headquarters.

“If quarantine cannot be controlled stably, we should keep in mind that the step-by-step recovery for normal life, which all people desperately hope for, will inevitably be delayed.”

The prime minister also stressed the importance of keeping tight quarantine measures through the next week when the true aftermath of Chuseok holiday is expected to take effect.

According to the KDCA’s data, the transmission route of 37.7 percent of all confirmed cases reported over the past two weeks remained unknown. With that, experts say the worst has yet to come as there could be thousands cases spotted after this week.

“Cases from the Chuseok holiday are nothing yet. It is not even time for infection cases from the holiday to be reported,” Professor Lee Jae-gap of Hallym University Medical Center told The Korea Herald.

“The number of confirmed cases were increasing last week before Chuseok. We are now seeing the numbers from then. We might have to face the situation where we will live just like this.”

Lee added that the vaccination rate needs to go higher to decrease the number of patients in severe conditions in order for the medical infrastructure to uphold the pandemic.

“The impact of Chuseok will be seen next week and the week after that. The number will go up by 2,000, 2,300, 2,500 and it will jump to 3,000 and 4,000,” said Chun Eun-mi, a professor at Ewha Womans University Medical Center.

“If you look abroad, one person infected with the delta variant transmits the virus to five or six people, not just one. That is why the numbers will double.”

The country’s first-round vaccination rate reached 72.3 percent as of Thursday while 44 percent of the population has been fully inoculated, according to the KCDA data.

As the country set its goal for the vaccination rate to reach 80 percent, health authorities continue to ask citizens to sign up for their jabs.

“Currently, 5.79 million people have not been vaccinated. The number of reservations (for vaccines) is only 160,000, which is 2.7 percent.” Lee Ki-il, a senior official at the Ministry of Health and Welfare, said in a briefing.

“At the moment, 90 percent of all confirmed cases come from those who have not received any vaccination at all or those who have not completely been inoculated (after getting their first shots). Please get vaccinated for our society, yourself and your family.”

The government’s vaccine reservation system will stay open through September 30.