South Korea on Thursday reported two more cases of the new coronavirus, with one believed to be the country's first human-to-human transmission, bringing the total number of people infected here to six.

Of the two, one, a 32-year-old man, recently returned from the Chinese city of Wuhan, the epicenter of the latest outbreak, but the other was confirmed to be the country's first human transmission case of the novel virus, according to the Korea Centers for Disease Control and Prevention (KCDC).

The first person-to-person infection involves a 56-year-old man who had been in contact with the country's third confirmed patient, who had, in turn, returned from China last week without showing symptoms.

The third patient was not subject to any limitations on his movement for days before testing positive for the new virus strain on Sunday, with the person he infected not under close observation by the health authorities so that he too could have inadvertently transmitted the disease to others.

The other person confirmed to be infected was in Wuhan on business and returned on Friday, according to the KCDC.

The two patients were immediately quarantined, it said.

The state agency said that it is in the process of determining who these two people met in the past few days so they can be contacted and checked.

Human-to-human infection has been a grave source of concern because it can easily lead to a sharp rise in infected cases.

From Jan. 3 onward, the KCDC said that it had closely checked 244 people for signs of the illness, with 199 having been cleared.

Common symptoms of the coronavirus, thought to have originated in Wuhan, central China, include fever, sore throat and breathing difficulties, with more acute cases involving chills and muscle pain.

The public health protection agency said earlier that it has developed a test procedure that can reduce the time it takes to determine if a person has been infected with the new coronavirus strain from the current 24 hours to just six.

The new method will be used initially by 18 public health centers on Friday and then be provided to civilian clinics and hospitals in early February, it added.

China, meanwhile, has confirmed 170 deaths and 7,711 people infected with the virus as of early Thursday.

Outside of China, Japan, Thailand, Vietnam, Singapore, Malaysia, Cambodia, Sri Lanka, Nepal, Taiwan, Hong Kong, Macao, the United Arab Emirates, Australia, France, Germany, Canada and the United States have confirmed cases of the new virus. Worldwide data showed 7,808 confirmed cases of the new coronavirus. (Yonhap)