The latest reports of a rebound in local novel coronavirus infections are all associated with imported cases. This hints at loopholes either in the current upon-arrival medical screening regime, or in the reliability of testing.

In one cluster of infections in Harbin, capital of Heilongjiang province, a resident who returned from the United States on March 19 reportedly transmitted the virus to her upstairs neighbor, who in turn infected four others, including family and friends, at the dinner table. And one of the four victims extended the chain of infection further by transmitting the virus to other patients and nursing staff at a hospital while receiving emergency treatment for a stroke.

The epidemic control authorities in Harbin have been admonished and urged to do immediate fence-mending.

The cluster of new infections in Harbin has prompted the authorities to postpone the previously scheduled reopening of schools for graduating classes across the province. But neither schools, nor local industries can afford to be indefinitely suspended.

The way COVID-19 infections are rebounding indicates the country will not be able to exert effective control on the outbreak without continuous vigilance on the part of local authorities and self-discipline on the part of individual citizens.

Heilongjiang confirmed 16 new cases from overseas on Wednesday. Of the 46 new confirmed COVID-19 cases reported on the Chinese mainland that day, 34 were imported, raising the total number of imported cases to 1,534.

Which is why China's coronavirus task force decided on Monday to boost health resources at its borders. It is essential that resources be sent to border towns such as Suifenhe, an otherwise inconspicuous small town in Heilongjiang on the China-Russia border, to assist local prevention and control efforts and prevent a second wave of infections.

And while the national health authorities have continued the suspension of all large-scale sports events where crowds may be involved, and they are enacting precautionary rules for reopening schools, which are necessary measures considering the proven effectiveness of social distancing, individual citizens must do their bit so as to make our overall containment strategy work.

Given the mounting pressure for the resumption of work and production across the country, how to prevent cluster infections has become a new priority for workplace safety.

That five of seven people dining at one table ended up infected in Harbin was an alert that it is still too early to let our guard down.

In the fight against the virus, we would do well to bear in mind Sun Tzu's words that the opportunity to secure ourselves against defeat lies in our own hands.