A novel coronavirus, also known as the Wuhan pneumonia, is spreading quickly since it broke out in the city of Wuhan in China’s Hubei province in late December. As of midnight Tuesday, increased testing had shown 440 confirmed cases and nine deaths. There is evidence of it spreading directly from human to human.

Beijing appears to have underestimated the epidemic at first and failed to contain it early. Chinese health authorities have typically been reluctant about disclosing information on patients and epidemics taking place in the country. They should actively share information with neighboring countries.

Saturday is Lunar New Year’s Day, one of the most celebrated holidays in both China and Korea. About 140,000 Chinese travelers are expected to come to Korea during the holidays. There are eight direct flights a week from Wuhan to Incheon. Hundreds of flights a week arrive to Korea by way of Wuhan. The holidays will be the most critical period in responding to the potential coronavirus spread.

Korea reported its first case Monday, when a 35-year-old Chinese woman from Wuhan tested positive for the coronavirus one day after arriving at Incheon Airport. She has been isolated at a state-run hospital in Incheon.

The Korea Centers for Disease Control and Prevention said the woman was not exposed to the local population, but Korea can hardly be labeled a safe zone. Many people come and go between Korea and China. Authorities in Thailand, Japan, Taiwan and the US have already identified at least seven cases, all involving recent travel from China.

A day before entering Korea, she was diagnosed with a cold in a hospital in Wuhan. It would be reasonable to suspect she may be one of many potential patients who did not know that they were infected. China’s National Health Commission said it was monitoring 1,738 people who had been in close contact with confirmed cases.

She reportedly showed no symptoms of the virus except for fever at the airport, before taking laboratory tests. This means that it is difficult to discern infected patients if they are in a latent period or at an early stage of the outbreak.

A Chinese scientist leading a government-appointed expert panel on the outbreak said Monday it is a human-to-human transmission phenomenon. There is no vaccine for the virus. Developing one could take a number of years. For now, checking the body temperatures of arrivals through thermal-imaging scanners, disinfecting airport and seaport facilities and quarantining suspected cases are all the government does as preventive measures.

Experts say the virus could be present in saliva and spread by airborne particles from coughing or sneezing. So it is wise to take simple preventions such as wearing masks and washing hands.

Authorities raised the alert level for infectious diseases from “attention” to “caution,” following the first confirmed case of the virus. The level needs to be maintained or upgraded, if need be, until after Lunar New Year holidays.

It is important for airports and seaports across the country to keep up a tight quarantine over the Lunar New Year holidays, when many Chinese tourists are expected to visit Korea. Considering more than 30 people who were in close contact with the first confirmed patient in Korea are under active surveillance, it is urgent to detect early if additional cases derive from them and respond quickly.

Seoul must urge Beijing to share information more actively while strengthening quarantine cooperation. Korean health authorities need to send urgent messages on the epidemic and preventive measures widely by text message to calm the people’s unnecessary anxiety.

When it comes to an epidemic of unknown cause, caution and prevention cannot be emphasized too much.