In a grim reminder that the epidemic prevention and control work brooks no complacency, hardly had a new cluster of infections of the novel coronavirus in the border areas of the southwestern Yunnan province been brought under control than a fresh cluster emerged in Jiangsu province, which has since spilled over to other provinces.

Zhuhai in Guangdong province and Wuhu in Anhui province have begun mass testing for the virus after asymptomatic infections were found linked to the cases in Nanjing, capital of Jiangsu province, which is now conducting a second round of citywide nucleic acid testing.

That the latest clusters of local infections in Yunnan and Jiangsu both originated from imported cases also reinforces the importance of containing imported infections and preventing them from causing local community transmission.

The most valuable lesson to be learned from the recent cases is that things may need to be done a little differently than before. While strict restrictions like regional lockdowns worked wonders in the initial fight against the virus, making the country the first in the world to bring the virus under control by and large, from the perspective of the recovery of both the economy and people's livelihoods, the mobility controls cannot be rigidly maintained.

The constantly mutating virus may be increasingly infectious, and new upticks are continuously reported, even in some of the most vaccinated countries and communities. But those new developments are not devoid of good news, since it has been found that in one country and community after another, vaccinated individuals have stronger resistance against the virus. It is true that many who have taken the jab may still be infected with the virus. But apparently most of those vaccinated only experience minor symptoms, and the likelihood of them suffering an acute condition is much lower than it is for those who have not been vaccinated.

The Nanjing cluster has borne this out. On the one hand, many of those who got infected had been inoculated. On the other hand, none of them had serious symptoms.

And the spillover cases, mostly travelers who had been to Nanjing airport, where the first victims work, have largely been asymptomatic. This, according to medical experts, conveys two messages: that people should remain vigilant and adopt the recommended personal protection measures even after they have been vaccinated; and that domestic vaccines significantly reduce the seriousness of infection.

The country has administered more than 1.5 billion vaccine doses, which is a great achievement. But it is far from enough for a country with a population of 1.4 billion. Substantially ramping up the vaccination program is imperative.

But given the harsh reality of the global situation, considerable efforts are needed to improve public awareness of the importance of vaccination.