For those who have already received news that the WHO announced that the COVID-19 pandemic was no longer a Public Health Emergency of International Concern, it should be noted that its Director General Dr Tedros Adhanom Ghebreyesus warned, too, that "However, that does not mean COVID-19 is over as a global health threat."

By ending its state of global emergency, the WHO seeks to support nations globally to downgrade their control over this pandemic. Cross-border population flow will hopefully resume, while the complicated procedures of traveling will end.

The measures to be taken by nations globally will be like what China has done since Jan 8, namely to suspend the class-A pandemic measures applied on COVID-19 and take class-B measures that match it. The just-concluded May Day holiday has witnessed 274 million tourists with a considerable consumption volume that indicates the potential of free travels in boosting the economy back to its right track.

The world has yet to be like what it was before the pandemic, but we are working toward that direction.

Yet the past three years, which have already become an untearable page in human history, should not be simply closed and covered with dust. There are quite a few lessons to be learned from the three years. Had the two successive sessions of US administrations, one Republican and one Democratic, fought the pandemic in a science-guided rather than politicized manner, a large part of the 1.12 million lives lost could have been saved.

Had the US and certain other Western nations better governed their societies, it would not have been a so fierce quarrel on whether to wear a mask, during which lives had already been lost.

There are many more. The COVID-19 pandemic will pass, but no one can be sure whether a new challenge named after a new number might come in whichever year. The lessons to be learned today will grant mankind better capability to cope with that tomorrow.