New COVID variant could emerge amid drop in surveillance, vaccination, WHO warns

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By Teresa Wright Global News

3rd December 2022 – (Geneva) World health authorities are closer than ever to being able to declare the emergency phase of COVID-19 over, but a growing decline in surveillance and vaccination could open the door to a new variant of concern, says the World Health Organization (WHO).

There are many tools available to protect individuals from severe illness and to track the virus and the ways it continues to mutate, but gaps in testing, sequencing and vaccination for COVID-19 continue to create “the perfect conditions for a new variant of concern to emerge that could cause significant mortality,” WHO Director-General Tedros Adhanom Ghebreyesus, said during a briefing Friday.

“We are much closer to being able to say that the emergency phase of the pandemic is over, but we are not there yet,” he said.

Last week marked one year since the WHO declared Omicron a variant of concern, and since then, the virus has continued to spread and mutate, with over 500 sublineages of Omicron now circulating around the world, the WHO said.

And while Omicron tends to cause less severe disease than previous variants, the virus’ uncanny ability to mutate in ways that allow it to escape immunity, either from vaccination or infection, means COVID-19 remains an ongoing threat, Tedros said.

It also means detailed information about how the virus is changing and behaving continues to be vital, he added.

For the last several months, WHO officials have been urging countries to beef up tracking, testing and sequencing of COVID-19, following a marked decline in surveillance measures as public health restrictions have been relaxed worldwide.

WHO has also added caveats to its weekly epidemiological reports on global COVID-19 circulation and case numbers, noting that any trends “should be interpreted with due consideration of the limitations of the COVID-19 surveillance systems.”

“These (limitations) include differences in sequencing capacity and sampling strategies between countries, changes in sampling strategies over time, reductions in tests conducted and sequences shared by countries, and delays in sequence submission,” the WHO said in its weekly epidemiological update on 30th November.

Collecting data on how the virus is moving through populations and conducting genomic surveillance is essential to monitor changes in COVID-19 and identify possible new variants of concern, said Maria Van Kerkhove, an infectious disease epidemiologist who serves as the WHO’s technical lead for the COVID-19 response.

But tracking variants has become challenging because of the decline in tracking measures, she said.

“We have a limited amount of information about the variants these days because surveillance has declined, testing has declined, sequencing has declined and that means there’s less data to analyze.”

To highlight this, Van Kerkhove said Friday that while there were at least 2.5 million cases of COVID-19 globally reported to WHO over the last week, this number is a “gross underestimate of the circulation of this virus around the world.“

“There are some wastewater estimates suggesting that number could be as much as five times higher in some countries,” she said.

“This virus is circulating rampantly around the world and we need to be able to absorb COVID circulation (and) COVID cases in the context of everything else that is circulating, including flu, including RSV and other pathogens that are out there.”

Canada is among many countries that have seen a significant reduction in testing for COVID-19, due to provinces and territories adopting testing policies that rely mainly on rapid tests to detect the virus, which are not tracked.

Laboratory, or PCR, tests, which not only determine positivity but also can detect genetic shifts in the virus, are now only performed for certain key populations in most parts of the country.

Without robust surveillance and sequencing data, knowledge about how COVID-19 may be shifting and mutating cannot be properly tracked, which leaves everyone in the dark about possible new variants of concern and the best ways to keep people healthy and safe, Van Kerkhove said.

“The virus still is not predictable,” she said during a WHO-hosted Q&A on 14th November.

“I think that’s why we need good surveillance, so that people can be looking at this every day. … We as public health professionals and scientists need access to that information.”

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