China has submitted genome sequence data from hundreds of recently sampled Covid-19 cases across the country to international database GISAID ahead of a meeting with the World Health Organization.

An increasing number of countries have imposed new controls on travellers from China as a result of their concerns about the current outbreak and the risk that new variants will emerge as a result.

The WHO said on Friday that it had invited Chinese scientists to present detailed data on viral sequencing ahead of a meeting of a technical advisory group on the evolution of the virus on Tuesday.

The data – collected from different areas of the country, including Beijing, Shanghai, Fujian, Guangzhou, Sichuan, Zhejiang and Inner Mongolia – was submitted over the new year holiday period.

A statement posted on GISAID’s homepage said no new variants of the virus had been detected, and the dominant strains were the Omicron subvariants BA. 5.2, BF. 7, BA. 2.75, and BQ. 1.1.

Moreover, the data indicated that BF. 7 outbreaks in Beijing and Fujian had a potential origin in Inner Mongolia, while the data from Shanghai showed a number of additional known lineages from multiple separate introductions.

The Chinese Centre for Disease Control and Prevention said last week that the BA. 5.2 and BF. 7 variants accounted for 80 per cent of China’s current cases.

The WHO has asked Chinese health officials to regularly share specific and real-time data on the country’s outbreak, including more genetic sequencing data, as well as data on hospitalisations, intensive care unit admissions, deaths and vaccinations.

The global health body has also urged it to strengthen viral sequencing, clinical management, and impact assessment.

The WHO’s director general Tedros Adhanom Ghebreyesus said more detailed information was needed to make a comprehensive risk assessment of the situation in China.

“We remain concerned about the evolving situation and we continue encouraging #China to track the #COVID19 virus and vaccinate the highest risk people. We continue to offer our support for clinical care and protecting its health system,” he posted on Twitter on Friday.

Chinese officials have had two meetings with the WHO since the country lifted its strict zero-Covid controls last month, Mi Feng, a spokesman for the National Health Commission, said on Tuesday.

“China is willing to continue to work with the international community, including the WHO, to help end the Covid-19 pandemic,” Mi said.

He said China had maintained close communication with the WHO over the past three years and the two sides had conducted more than 60 technical exchanges in areas such as epidemic control, medical treatment, vaccine research and Covid-19 origin-tracing.

As China reopens after three years of Covid isolation, a number of countries have announced new entry restrictions on travellers from China, while others such as Italy and Japan require a negative test on arrival.

Some countries, including the United States, attributed the change to China’s lack of information on genome sequencing and Covid-19 variants.

“Variants of the Sars-CoV-2 virus continue to emerge in countries around the world. However, reduced testing and case reporting in [China] and minimal sharing of viral genomic sequence data could delay the identification of new variants of concern if they arise,” the US Centres for Disease Control and Prevention said.