Travelers at Meilan International Airport in Haikou, south China's Hainan Province, December 9, 2022. (Photo: CFP)

The possibility is relatively low that XBB and BQ.1 strains that are circulating in other countries will become prevalent in China in the first half of 2023 or trigger a spike in infections, according to a senior Beijing-based respiratory expert.

According to the latest information released by the Chinese Center for Disease Control and Prevention (China's CDC) on Wednesday, China has continued to monitor the mutation of COVID-19.

The China CDC has selected sentinel hospitals in each province after December 2022 to monitor the mutation of the virus in outpatient (emergency) cases, severe cases, deaths and some key groups. At the same time, the virus mutation monitoring have been carried out at land, water and airports. The results showed that the prevalent strains in latest round of epidemic were BA.5.2 and BF.7, and no new mutant strains were found.

Will XBB and BQ.1 strains trigger another spike in COVID-19 infections this spring? Li Tongzeng, chief physician from the respiratory and infectious diseases department at Beijing You’an Hospital, told the health channel of the People's Daily on Wednesday that with the reopening of the national borders, there may be more local cases of BQ.1 and XBB strains in the future, but generally speaking, the possibility of epidemics of these two strains in the first half of this year is relatively small.

On January 18, Gao Fu, former head of the China CDC, said in an interview with China Newsweek that XBB1.5, a branch of XBB, has become an increasingly prevalent strain in the US. XBB.1.5 has significant immune escape, almost equivalent to an entirely new virus. At the same time, the BQ.1 strain is also circulating in many countries.

"Most people in China were infected in December in 2022 and January this year, and the antibodies produced after the infection can protect them for at least three or four months. By March or April this year, most people should still be protected by the antibodies," Li said.

He pointed out that current studies on BQ.1 and XBB showed that although their immune escape ability is strong, the strains we are currently infected with such as BA.5 still have a certain protective effect against these two strains.

On January 17, Xu Wenbo, head of the National Institute for Viral Disease Control and Prevention with the China CDC said at a news conference that, unlike BA5.2 and BF7, the BQ. 1 and XBB have not yet showed their spread advantages in our country. It is expected that the proportion of transmission of BQ.1 and XBB will gradually increase, but they will not cause a new epidemic surge alone, Xu predicted.

To prevent BQ.1 and XBB, as with the prevention of other mutant strains, we should strengthen the monitoring of viral mutation and disease severity, protect high-risk groups, and encourage the public to maintain high levels of self-protection. 

Li said that we don't have to worry too much about these two strains. “Now many people have infected, and they have gained a lot of experience in protection. At present, we should still insist on wearing masks, washing hands frequently, and open windows for ventilation,” he said.