South Korea's total virus caseload topped 30,000 on Friday, 10 months after its first confirmed case in late January, and its virus fight is facing another potential wave of outbreaks amid the nearing winter season.

The country reported 363 new COVID-19 cases Friday, including 320 local infections, raising the total to 30,017, according to health authorities. It marked the third straight day that daily virus cases rose by over 300.

Since the first case was reported on Jan. 20, the total number of fatalities reached 501.

Without imposing stringent lockdowns, South Korea has well flattened the virus curve through swift and mass testing, though it suffered the first and second waves of the virus outbreak in February-March and August-September, respectively.

But the country's virus fight stands again at a critical juncture as daily infections rebounded above 300 this week due to sporadic cluster infections from medical and public facilities, as well as private gatherings.

The country faced its first wave of the outbreak tied to the minor religious sect of Shincheonji in the southeastern city of Daegu in late February and early March. Cases traced to the sect reached about 5,200.

Another major setback came from more than 270 cases tied to clubs in Seoul's popular nightlife district of Itaewon in May.

The second wave gripped the country in late August in connection with a church in northern Seoul and an anti-government rally on Aug. 15. The number of cases tied to Sarang Jeil Church came to some 1,170, while cases traced to the protest reached 650.

"Another wave of the outbreak has already started, as expected for the autumn and winter seasons," said Kim Woo-joo, an infectious disease specialist at Seoul's Korea University.

"Since Monday, the virus curve has gone up at a steeper pace.

We have to well prepare for this winter," he said.

A respiratory virus usually proliferates when the weather is cold and dry as its survival largely depends on changes in temperature and humidity. People are more susceptible to infection as their immune systems weaken in the winter.

The current situation may be tougher than the past waves of virus outbreaks as infections are being reported sporadically at diversified places across the nation.

The virus has been currently spreading at almost every corner of daily lives, including via meetings of family and friends, and at schools, workplaces and saunas.

The greater Seoul area -- home to half of the country's 51.6 million population -- has faced spikes in virus infections.

The accumulative number of virus cases in Seoul reached 7,236 as of midnight Friday, accounting for 24.1 percent of the total patients here. The total tally surpassed the 7,211 cases in Daegu, once the epicenter of the virus outbreak.

Experts said it is important to thoroughly keep social distancing measures to cope with the virus outbreak in the winter as vaccines and proven treatments are not available.

Since Thursday, the country has raised social distancing measures by one notch to Level 1.5 from the lowest under its new five-tier scheme for the next two weeks in the greater Seoul area and the southwestern city of Gwangju.

Health authorities said they will consider raising infection prevention measures to Level 2 in the Seoul metropolitan area if the daily average number of COVID-19 cases tops 200 per week.

Earlier in the day, Prime Minister Chung Sye-kyun issued a public message that calls the public to refrain from holding year-end gatherings and non-essential outdoor activities.

"This winter will be the biggest challenge in the virus fight," said Choi Won-suk, an infectious disease professor at Korea University Ansan Hospital. "The key to curbing the virus spread will be people's participation." (Yonhap)