Major Chinese cities have passed peak COVID-19 infections, with the number of patients in emergency wards dropping and patients in intensive care plateauing, according to a senior health official.

Jiao Yahui, head of the National Health Commission's medical administration bureau, said smaller cities and rural areas have also witnessed large numbers of infections recently and will face a peak in severe patients and those needing emergency treatment during the Spring Festival travel rush.

In an interview with China Central Television on Sunday, Jiao said that the number of patients contracting Omicron and showing symptoms of pneumonia accounts for around 8 percent of the total in 2022.

However, as China has a large population, even a small percentage can result in a large overall figure, she said.

The country as a whole will probably not witness a peak in infections during the Spring Festival travel rush but will likely have a peak in critical patients and those in need of emergency treatment, she said.

With the number of patients needing intensive care rising, the occupancy rate of ICU beds increased rapidly between December and January, rising from 54 percent on Dec 25 to around 80 percent currently.

The large flow of people during the Spring Festival travel rush is increasing pressure on treating severe patients in rural areas, as the country's healthcare is weaker outside cities, she said, adding that the biggest challenge is to transfer severe patients from rural to urban areas.

Chen Cao, a researcher at the Chinese Center for Disease Control and Prevention, said that China had detected imported cases caused by the XBB subvariant of Omicron, as well as 16 domestic cases, most of them in October.

However, the subvariant has not so far become dominant and there is currently a low possibility of a large-scale epidemic resulting from XBB, he said.

Antibodies in individuals previously infected with the BA.5.2 and BF.7 subvariants will remain relatively high for a short period and should provide effective cross-protection against other Omicron variants, including XBB, he said, adding protection can even last up to six months in certain people.

China has strengthened monitoring of Omicron variants, especially outbreaks caused by XBB around the world, and of the risk of imported infections, he said.

Although the XBB subvariant is more transmissible, it has not led to more critical illness or deaths, he added.

Chang Zhaorui, a researcher at the Chinese Center for Disease Control and Prevention, said people are advised to take personal protection measures, such as washing their hands frequently, wearing masks, properly ventilating spaces and maintaining social distancing to enjoy Spring Festival safely.

They should refrain from holding large family gatherings and be careful not to increase the risk to elderly family members, she said.

People should get vaccinated as quickly as possible and continue to monitor their health. Those showing symptoms or who test positive should stay in well-ventilated, separate rooms and minimize contacts with others, Chang added.