Over the past three days, about one-third of the newly confirmed cases of the novel coronavirus in the country outside of Hubei province, which has been the heart of the epidemic, come from abroad — seven from Italy, four from Iran and one from the United Kingdom.

When the nation is seeing a ray of light near the end of a long dark tunnel, the inflow of cases from outside threatens to dash rising hopes that life will return to normal.

Although China still has the largest number of cases, what is more worrisome is that the increase of new cases overseas is nearly 10 times more than that in China.

As 70 countries have reported more than 10,000 confirmed cases as of Tuesday, and the number of new cases is rising exponentially, it is fair to say the epidemic has transformed from a people's war of China to a people's war of the world.

It is the all-out and costly struggle China has waged against the virus that has helped bring the epidemic under control, including it seems in Hubei. But those hard-won gains might be lost at any time, if the country, which is keeping its doors open, does not prevent new cases from entering it.

The inspection and quarantine authorities at customs must regard themselves as a defensive line, and screen all people entering or leaving the country and quarantine any arriving or departing who are suspected of being infected with the virus. If all countries can filter out the virus carriers as they enter or leave, the spread of the epidemic will be minimized.

At the same time, given the long incubation period of the virus, it is strongly advised that all unnecessary cross-border trips be postponed for the time being.

So far, the only substantial resistance the virus has encountered is in China. And the country is doing all it can to help countries combat the epidemic.

The world is undoubtedly facing increasing uncertainties as the epidemic quickly spreads. It is strongly advised, as the World Health Organization has reiterated, that all countries take the initiative to adapt China's measures to their respective conditions, and attempt to detect, isolate and treat the infected and suspected infected as early as possible.

Such actions have been demonstrated necessary. Any belated moves will only make the fight against the virus more costly, both in terms of economic losses and people's lives.

In the face of this common threat disputatiousness will only serve the world ill.