WHO warns of growing presence of new recombinant coronavirus in Europe

XBB.1.5 impact needs to be assessed

In the first five weeks of 2022, variant information on 1.2 million cases was submitted as part of weekly surveillance data to WHO and its partner the  European Centre for Disease Prevention and Control (ECDC). However, this declined to about 90 000 cases in the last five weeks of the year, Kluge said.

He noted that the WHO commends European countries that have maintained strong genomic surveillance – including Denmark, France, Germany and the United Kingdom. 

Indeed, recent data from some of these countries are starting to indicate the growing presence of the new XBB.1.5 recombinant virus that has already been spreading rapidly across the United States,

said Kluge, adding that

XBB.1.5. variant cases in our region are being picked up in small, but growing numbers, and we are working to assess its potential impact.

He stressed that after three long pandemic years – with many countries grappling with overstretched health systems, shortages in essential medicines and an exhausted health workforce – "we cannot afford more pressures on our health systems." 

Such a threat, he added, could come from a new variant of concern, anywhere, anytime – including right here in Europe and central Asia. 

XBB.1.5 situation in Europe

XBB.1.5 is a sub-lineage of XBB with an additional spike RBD mutation S486P. This lineage was first detected in United States (US) with the sample collection dates as of 22 October 2022, and since then the lineage has been seen increasing. 

"XBB.1.5 is a sub-lineage of the SARS-CoV-2 lineage XBB, and is currently estimated to have a large growth advantage over previously circulating lineages in North America (109%) and Europe (113%), although these estimates are associated with significant uncertainty.

There is a risk that this variant may have an increasing effect on the number of COVID-19 cases in the EU/EEA, but not within the coming month as the variant is currently only present at very low levels in the EU/EEA,

the ECDC said in an XBB.1.5 assessment report on Monday.

As of 9 January 2023, 4 770 sequences have been deposited in GISAID EpiCoV belonging to XBB.1.5 with the mutational profile in Spike region - Q183E, F486P and F490S. Most of these submissions are from the US (4111 sequences), and the United Kingdom (202 sequences), and the variant has also been detected in several other countries, including EU/EEA countries – Austria, Belgium, Czechia, Denmark, France, Germany, Iceland, Ireland, Italy, the Netherlands, Portugal, Romania, Slovenia, Spain, and Sweden.

The proportion of the variant in the EU/EEA is lower than 2.5% for the last two weeks of 2022 for all countries where variant proportions at this low level can be accurately estimated.

The ECDC underlined that the rapid growth in the US does not necessarily mean that the variant will become dominant in the EU/EEA, since major differences in variant circulation between North America and Europe have been observed several times during the pandemic. 

The most likely explanation of the growth advantage is the already high level of immune escape demonstrated by XBB, combined with the effect of the spike change S486P.

The most likely explanation of the growth advantage is the already high level of immune escape demonstrated by XBB, combined with the effect of the spike change S486P. This mutation has previously been rare during the pandemic, probably due to it requiring two nucleotide substitutions in the same codon to change from phenylalanine to proline. 

"A recent preprint demonstrates that XBB.1.5 is not associated with a higher reduction in neutralisation by vaccine and convalescent sera compared to XBB.1, but that it is associated with a higher ACE2 affinity, which could indicate that the advantage of XBB.1.5 compared to XBB.1 could be caused by an increase in intrinsic transmissibility," the ECDC said.

Further laboratory and epidemiological investigations are required to elucidate the mechanism of the growth advantage conferred by this change for the XBB variant specifically. There is currently not enough information available to assess any change in infection severity associated with the variant.

Surge in new cases in China

As regards the Covid situation in China, Kluge said that from the information available to WHO, the SARS-CoV-2 virus variants circulating in China are those that have already been seen in Europe and elsewhere. 

"We share the current view of the European Centre for Disease Prevention and Control (ECDC) that

the ongoing surge in China is not anticipated to significantly impact the COVID-19 epidemiological situation in the WHO European Region at this time,

he said.

At the same time, Kluge warned not to be complacent. 

"While we acknowledge that China has been sharing virus sequencing information, we need detailed and regular information, especially on local epidemiology and variants, to better ascertain the evolving situation," said Kluge.

He stressed that it is not unreasonable for countries to take precautionary measures to protect their populations, but with regard to countries introducing precautionary travel measures at this time, he said they are calling for such "to be rooted in science, to be proportionate and non-discriminatory."

That is not to say that “we recommend testing of patient of passengers coming from the US at this stage. Countries need to look at the evidence base for pre-departure testing”, WHO’s senior emergency officer for Europe, Catherine Smallwood, told a news briefing.

Passengers should be recommended to wear masks in high-risk settings such as long-haul flights, she added, “this should be a recommendation issued to passengers arriving from anywhere where there is widespread Covid-19 transmission”.

Hungary's official government website sharing epidemiological information has been taken off the web as of 1 January 2023. They did not just simply stop to provide updates, the website (koronavirus.gov.hu) is no longer available. Covid statistics are currently provided to state-run newswire MTI that is generally available only to the press. The move has further worsened the transparency of already scarce and unreliable information about the spread and impact of coronavirus in Hungary.

Cover photo: Getty Images