The Biden administration announced Wednesday that travelers from China, Hong Kong and Macau will be required to present negative Covid-19 tests before entering the United States, a move it says will slow the spread of the coronavirus. This requirement is effective from Jan. 5.
The Centers for Disease Control and Prevention’s announcement came amid growing concerns about a surge in cases in China and the country’s lack of transparency about the outbreak there.
The testing requirement applies to air travelers regardless of their nationality and vaccination status, CDC officials said. This applies to travelers from China who enter the US via a third country and to other destinations via the US.
China’s Covid outbreak has worsened in recent days, with local governments reporting Hundreds of thousands of infections per day. Videos obtained by The New York Times program Sick patients are thronging the hospital premises. But it is difficult to monitor the situation in real time because China Trusted doesn’t publish covid data.
After three years of insisting on the “Zero Covid” policy, China created it A sudden turn It scrapped the policy in early December after mass protests over the lockdowns threatened the ruling Communist Party. Since then, there has been an explosion of cases in Beijing.
Scientists in Hong Kong have reported that the omicron subvariant Known as BF.7 for the Beijing explosion. That variant is a sub-series of the BA.5, which until recently dominated the US. But the BF.7, while it has been in the US for several months, shows no signs of competing here with Omicron’s other versions.
The CDC estimates that BF.7 was 4 percent at the end of December, and has been low since November. Other omicron subtypes, which scientists believe are more adept at evading existing immune responses, currently dominate in the United States.
Scientists have shown in recent days, at least, that the variant immune responses fueling China’s outbreak are not necessarily so effective at setting aside. Since very few people in China have been affected by versions of Omicron before, it’s likely that one of the Omicron subtypes that have been making the rounds around the world recently will make their way there.
In a population like China that has very little immunity to infections, the dominant variant is not necessarily the best at getting around those immune responses, but simply the one that flares up.
“In one way or another, whatever is picked up first is going to dominate,” says James Drewer, an expert on infectious disease modeling at Monash University in Melbourne, Australia.
This is a growing story. Check back for updates.