The just-concluded May Day holiday, which was specifically prolonged to facilitate domestic travel, was an invaluable boon for the country's service sector, which has been badly affected by the outbreak of the novel coronavirus.

The holiday provided reassuring signs that domestic consumers remain willing and able to spend, with the photos of packed tourist sites across the country shared on social media suggesting the anticipated 200 million person-times of holiday travel was not being unduly optimistic.

Lifting the restrictions on domestic travel originated from the government's confidence in the country's relatively successful containment of the pandemic at home, and the fact that no new domestic infections have been reported so far provides some initial reassurance that its confidence was not unfounded.

But until it is known for certain that there have been no new domestic infections, proper discretion must be maintained. That means the appeal by the public health authorities for 14 days of self-monitoring by all holiday travelers should be taken seriously.

There is no denying the first-stage performance of the country's pandemic containment regime has appeared exceptionally good. To date, all places that had been designated as high risk or middle risk have officially become low risk. But as the national pandemic prevention and control authorities cautioned, this is no time for people to relax their vigilance as the virus remains particularly rampant in some neighboring countries.

Local public health authorities have reported multiple cases of imported infections traceable to India, where new variants of the virus are wreaking havoc.

Considering the sudden increase in domestic holiday trips, and the known local travel history of some of the imported cases, it is important to determine if these imported infections had any contact with domestic holiday travelers.

While those who traveled during the holiday should follow the 14-day self-observation advice for their own and others' safety, authorities at all levels must make sure no possible clue of potential new infections is neglected. Local epidemic prevention and control agencies must keep in mind the importance of early reporting and early intervention, and respond timely to any suspected domestic cases.

Close and smooth interaction between individual citizens and government agencies was instrumental in the country's initial success in controlling the epidemic situation at home. It will be even more so in the next stage.