CNN
—
As the world enters a new year, many public health and infectious disease experts predict that monitoring for novel coronavirus variants will be an increasingly important part of Covid-19 mitigation efforts, and some are putting their attention on a rise in cases in China.
Sub-variants of the Omicron coronavirus variant continue to circulate around the world and “we’re seeing Omicron do what viruses do, which is detect mutations along the way that help it evade some immunity induced by infection or vaccination.” previous”. said Andrew Pekosz, a microbiologist and immunologist at the Johns Hopkins Bloomberg School of Public Health in baltimore
“We haven’t seen any major leaps in terms of Omicron’s evolution in some time,” he said. But “it’s getting to that stage where it’s something we have to continue to monitor.”
In the United States, Omicron’s XBB.1.5, BQ.1.1, BQ.1, BA.5 and XBB subvariants are causing nearly all COVID-19 infections, according to data from the US Centers for Disease Control and Prevention..
For this week, the CDC estimates that XBB.1.5 now causes 40.5% of cases in the US, followed by BQ.1.1 at 26.9%; BQ.1 at 18.3%; BA.5 at 3.7%; and XBB at 3.6%.
“SARS-CoV-2, the virus that causes COVID-19, constantly changes and accumulates mutations in its genetic code over time. New variants of SARS-CoV-2 are expected to continue to emerge,” CDC researchers write to your data tracker. “Some variants will come and go, while others will come and continue to spread and may replace older variants.”
Omicron’s ramifications also seem to dominate globally, but as the coronavirus continues to spread, especially in China after Beijing’s rapid easing of restrictions, there are now concerns about where Covid-19 trends could head in 2023. and the risk of new variants emerging.
“It’s a concern,” said Dr. William Schaffner, a professor in the Division of Infectious Diseases at the Vanderbilt University Medical Center in Nashville and medical director of National Foundation for Infectious Diseases. “And that, of course, has led to the recent announcement by the CDC that they are going to force people coming into this country from China to get tested and come back negative before they can enter the country.”
US health officials announced Wednesday that, starting January 5, travelers from China will be required to show a negative Covid-19 test result before flying into the country. Passengers traveling to the US from China will need to get tested no more than two days before flying and provide proof of the negative test to their airline before boarding.
Officials also announced that the CDC is expanding the traveler-based Genomic Surveillance Program to airports in Seattle and Los Angeles, bringing the total number of participating airports to seven with about 500 weekly flights from at least 30 countries covered, including around than 290 weekly flights from China and surroundings.
The Chinese government hasn’t been sharing much information about the genetic makeup of the viruses it’s seeing there, Schaffner said.
“Because the Chinese government wasn’t doing that, that was the main reason the CDC put this new travel requirement in place. It’s certainly not to prevent simple transmission of Covid from China here. We have a lot of Covid. That it would be like telling people not to pour a bucket of water in a swimming pool,” he said. “This travel proof requirement is a way to buy some time and help create a kind of barrier between us and China, in case of a new variant suddenly appearing in that country”.
He added that the US will need “as much time as possible” to update vaccines and antivirals to respond to a possible emerging variant of concern.
The US testing requirements for travelers will “buy some time” but will not prevent new cases of Covid-19 from arriving in the United States or new variants from emerging, said Dr. Carlos Del Rio, associate dean executive at Emory School of Medicine and Grady Health System in Atlanta.
“Honestly, I don’t think we’re going to see much benefit,” he said of the travel requirements. “The most important thing that we need right now is that we need the Chinese to be more transparent and tell us exactly what is going on, and that is a diplomatic decision. It’s about diplomacy.”
As for the genetic data on coronaviruses in China being accessible to the public, “it really is a bit of a black hole,” Pekosz said. Almost 250 million people in China may have contracted Covid-19 in the first 20 days of December, according to an internal estimate from the country’s top health officials, Bloomberg News and Financial Times reported last week.
“For me, what really concerns me is the ongoing infections and whether they are producing more variants in China that might be of particular concern to us, and testing people before they get on a plane is not going to answer that question.” Pekosz said. . .
“What we really need is to do a much better job of sequencing the viruses of people traveling from China so that we can help understand what kind of variants are circulating there,” he said, adding that during the pandemic, Chinese officials they have not been very transparent about their data on variants.
The constant spread of a virus is what can lead to the appearance of variants. The more a virus spreads, the more it mutates.
“For a variant to emerge, and this is true not only for covid, but also for influenza and many other viruses, the most critical thing is that the more cases you have, the more likely it is that the virus will start to accumulate mutations that could having the ability to evade immunity more effectively or to transmit more effectively,” Pekosz said.
“So when you have a situation like the one that’s starting to happen in China, where you’re going to have millions and millions of infections, each one of those infections is just an extra opportunity for the virus to pick up a random mutation that could do it better for infecting people,” he said. “Combine that with the fact that the Chinese population has been using less-than-optimal vaccines and apparently hasn’t been as good at putting boosters into their population as other countries have, that means that probably there is a lower amount of immunity in the population.”
Chinese health authorities have “markedly increased” the number of coronavirus genome sequences and other related data that they are sending to the GISAID world databasean initiative that maintains databases for scientists from around the world to share data on flu viruses and coronaviruses.
But many experts argue that it is not enough.
GISAID said in an email to CNN on Wednesday that the China Centers for Disease Control and Prevention and several regional centers in the country “have markedly increased the number of submissions of genomic sequences and associated metadata from samples taken in recent years.” days”.
The GISAID Data Science Initiative announced that it has published genomic sequence data from 167 SARS-CoV-2 samples collected during the current outbreak in China. SARS-CoV-2 is the name of the virus that causes Covid-19. GISAID also confirmed that the sequences from China “all closely resemble known globally circulating variants seen in different parts of the world between July and December 2022,” compared to the 14.4 million genomes in the database. GISAID data.
“These latest data provide a snapshot of the evolution of Omicron variants and show that these most recently shared sequences from China are closely related to variants that have been circulating for some time,” according to the GISAID Data Science Initiative. .
Covid-19 is in a relatively “stable” state right now in the United States, but the nation still records about 350 disease-related deaths each day, said Dr. Jessica Justman, an associate professor of medicine in epidemiology. on the Columbia University Mailman School of Public Health and Senior Technical Director of the ICAP Global Health Program.
While covid-19 levels remain well below previous surges, trends are on the rise in some parts of the US, new hospital admissions are up nearly 50% over the past month, and there is a growing concern that the number of cases will skyrocket after the winter. Holidays.
To reduce the risk of further spread of covid-19, Justman said, it will be important for people in the new year to continue to stay up-to-date with their covid-19 vaccinations.
Only 14.6% of the US population 5 years and older have received their updated booster shot, according to CDC data.
“So where are we going? That brings me to China,” Justman said.
“I am concerned that China right now is a giant incubator for SARS-CoV-2. There is the potential to have so many infections and with that, new variants,” she said.
“I think we’re going to look at new variants of concern” in 2023, Justman said. “The question is: Will we go back to a point where we have a variant of concern that causes such severe disease that we don’t get the benefit of our previous infection protection and vaccinations?” … I’m going to be optimistic and say I don’t think we’re going to go back to that point.”
