South Korea on Wednesday reported more than two-thousand new cases of COVID-19 cases for the first time in a week.
So-called breakthrough COVID-19 infections are surging, now topping three-thousand.
Despite being fully vaccinated, according to the health authorities, people in their 30s had the highest rate and it was lower for older people.
So far, those given the Johnson & Johnson vaccine have the most breakthrough cases.
Meanwhile, the Delta variant now accounts for around 95 percent of new cases.
Considering this, authorities say the fourth wave is likely to be around for the foreseeable future.