South Korea’s fight against the new coronavirus may be entering a new phase of local transmission, the head of the state disease control center said Tuesday, as the country identified a third case with an unclear infection route.

“The situation here and abroad suggests we’re entering a new phase,” Jung Eun-kyeong, head of the Korea Centers for Disease Control and Prevention, said in a press briefing.

“We have three cases yesterday and today with no overseas travel history. … As we expand screening and conduct more tests, there is a chance that we will see more of such cases,” the director said.

Efforts to contain the virus that causes COVID-19 will now follow a two-pronged strategy, she added. One is to block the virus from China and other countries with a high number of confirmed cases, and the other is to stop its spread through local communities.

This, however, does not mean the virus is spreading uncontrollably, Jung stressed.

The advice for the general public remains the same -- observe personal hygiene practices, she added.

South Korea has 31 confirmed cases of the virus, which originated in the Chinese city of Wuhan and has left over 1,800 people dead and 17,000 infected in mainland China. Of the 31, 12 have fully recovered.

The latest patient, identified Tuesday morning, is a 61-year-old Korean woman who lives in Daegu and was confirmed not to have been abroad recently. After testing positive at a public health center, the woman was placed under quarantine for treatment and monitoring.

Health authorities said they are tracing the patient’s steps and working to find out how she contracted the illness.

This is the third case in the country that could not be traced directly to China or known virus patients.

The country’s 29th and 30th virus patients, who are married, also did not have contact with other confirmed patients and had not been abroad recently.

The number of people being checked for the virus and under quarantine came to 957 as of early Tuesday, up from 708 the day before, the KCDC said.

By Korea Herald staff and news reports (khnews@heraldcorp.com)