The Biden administration, fearing that the rise in coronavirus cases in Beijing could create a new and more deadly variant, announced on Wednesday that it would require travelers from China, including both Hong Kong and Macau, present a negative Covid-19 test prior to entering the United States states.
According to an announcement by the Centers for Disease Control and Prevention, the requirement will go into effect on January 5. Officials at the agency said they are deeply concerned about China’s lack of transparency about China’s lack of transparency. its outbreak – and especially its failure to track and sequence the variants and sub-variants circulating within its borders.
CDC officials said the testing requirement would apply to airline passengers regardless of their nationality and immunization status. It will also apply to travelers from China entering the United States through a third country or those connecting through the United States to other destinations. Italy and Japan have imposed similar restrictions, and India has required negative Covid-19 test reports and random screening at airports for passengers arriving from China, Japan, and South Korea. China, Hong Kong and Thailand.
But as they did when President Donald J. Trump imposed travel restrictions during the pandemic, some experts have questioned whether asking for testing would be beneficial – especially given the number of Infections spiked in some parts of the United States. In the northeast, scientists say the spread of the virus is being fueled by a sub-variant of Omicron, XBB, which appears to be spreading faster than those associated with the dominant variant in Beijing.
“Politically, I understand why it has to be done, but the bottom line is, it is,” said Michael T. Osterholm, director of the Center for Infectious Diseases Research and Policy at the University of California. a false sense of security when we are actually slowing transmission.” University of Minnesota.
China’s Covid outbreak is getting worse in recent days, with local authorities reporting hundreds of thousands of infections every day. Videos obtained by The New York Times show sick patients crammed into hospital corridors. But the situation is difficult to track in real time because China does not publish reliable Covid data.
The CDC also announced on Wednesday that it is expanding its voluntary genomic surveillance program to look for new variants in anonymous swabs taken from international travelers at major US airports, including Los Angeles and Seattle.
Find out the situation in China
The Communist Party has ignored the restrictive “no Covid” policy, sparking mass protests that are a rare challenge for the Communist leadership.
Some experts worry that instead of encouraging transparency from China, the policy could make the Chinese even less open.
“The most important strategy right now is that we need to improve our political and diplomatic communication with China,” said Dr. Carlos del Rio, an infectious disease expert at Emory University. He said he feared that the new Biden administration policy would work “in the opposite direction.”
But Jennifer Nuzzo, director of the Pandemic Center at Brown University’s School of Public Health, said the administration had little choice.
“I think they are trying to put pressure on China to properly uphold its international responsibilities,” she said, adding that the “small agreement” calls on countries to share data. pandemic data “will only be effective if countries call for it”. bad behavior.”
After three years of insisting on a “no Covid” policy, China abruptly changed in early December and lifted that policy, following mass protests against the blockade order that threatened the Communist Party’s rule. permission. Since then, there has been a significant increase in the number of cases in Beijing.
A major concern among public health officials is that the Chinese people have little natural immunity, allowing the virus to spread rapidly. In contrast, rapid spread creates new opportunities for the virus to grow, posing the risk that new variants could emerge and spread to other parts of the world.
That doesn’t necessarily mean that a more dangerous variant will emerge in China any time soon, scientists say. Over the last year, people in the United States have been infected with episodes of the Omicron sub-variant. But since people in China are essentially isolated from those versions of the virus, scientists think any of them could take off there.
“In a sense, whatever comes first is likely to prevail there,” said James Wood, an infectious disease expert at the University of New South Wales in Sydney.
Some variation in the past is thought to have emerged as the virus mutates during prolonged infection in people with compromised immune systems, suggesting that the extent of transmission in a single site may not decide on its own the possibility of developing new variants.
Jeffrey Shaman, an infectious disease modeler at Columbia University, said: “Despite the argument that the more people become infected, the greater the chance of mutating and developing a new variant. New variants mainly develop during person-to-person transmission or in people with prolonged infection.”
Scientists in Hong Kong reported that a sub-variant of Omicron called BF.7 caused the outbreak in Beijing. That variant is a subline of BA.5, which until recently dominated in the United States. But BF.7, despite being present in the US for many months, has not shown any sign of superiority compared to other Omicron versions in this country.
The CDC estimates that BF.7 accounted for 4% of cases at the end of December, and it has become less common since November. Other sub-variants of Omicron that scientists believe may be better at Evasion of existing immune responses, including XBB, is now more common in the United States.
In the United States, the CDC estimated last week that the XBB sub-variant had developed accounting for nearly a fifth of cases in the country, up from just 3% of cases a month earlier.
Scientists say XBB is spreading particularly rapidly across the northeastern United States, accounting for more than half of all new infections there. And it appears to have an advantage over the BQ.1 Omicron sub-variants that have recently prevailed in the United States, the scientists said.
Scientists are in the early stages of studying the XBB sub-variant. They say that an even newer version of that sub-variant has appeared, called XBB.1.5. Preliminary studies have suggested that the newer version is adept at evading existing immune responses and binding to human cells.
Especially in the next few months, scientists say, when many people in China have a certain degree of immunity to previous infections and the virus is under more pressure to evolve there. , it is important to scan for new variants, the scientists said.
Dr Wood, of the University of New South Wales, said: “It would be great if China provided some sort of summary of what variations they are seeing. “If not, eventually that will be discovered during genomic surveillance in Europe or the United States or wherever people travel.”
For now, however, China does not pose too much of a risk of creating a new variant, he said.
“We have had a large number of infections worldwide,” he said. “That’s more cases than happened in China alone.”
Emily Anthes and Karan Deep Singh contribution report.