The United States will require travelers from China, Hong Kong and Macau to show a negative COVID-19 test before entering the U.S. as restrictions lessen and cases surge in China.
The U.S. Centers for Disease Control and Prevention announced the measure Wednesday to go into effect on Jan. 5 for all passengers over the age of 2. Passengers must show a negative PCR or monitored antigen test no more than two days before their departure, whether it is a direct flight or an indirect one through another country.
The monitored test must be overseen by a telehealth service or a licensed provider and authorized by the U.S. Food and Drug Administration.
The CDC pointed to the surge in COVID-19 cases in China and "the lack of adequate and transparent epidemiological and viral genomic sequence data being reported from" that country.
"Reduced testing and case reporting in (China) and minimal sharing of viral genomic sequence data could delay the identification of new variants of concern if they arise," the CDC said in a news release.
Passengers also flying through South Korea's Incheon International Airport, Toronto Pearson International, and Vancouver International will be required to provide a negative test if they have been in China in the last 10 days.
"These three transit hubs cover the overwhelming majority of passengers with travel originating in the PRC and the Special Administrative Regions," the CDC said.
Passengers who tested positive more than 10 days before the flight can provide documentation of recovery from the virus in place of a negative test result.
The move to require testing for all passengers from China, Hong Kong or Macau comes two days after China dropped quarantine requirements for passengers arriving from abroad, effective Jan. 8.
Widespread protests against China's zero-COVID policies erupted across the country in November, prompting China to roll back a series of measures, including mass testing. But with the loosening of restrictions came a large COVID surge that could infect a total of 800 million people over the next few months, Chinese public health officials say.
The U.S. is also expanding its voluntary genomic testing program (TGS), which collects anonymous nasal swabs from arriving international travelers to detect new and rare COVID variants. The CDC is adding Seattle-Tacoma International Airport and Los Angeles International to bring the total number of airports participating in the program to seven.
"During the initial weeks of the Omicron surge, TGS detected two Omicron subvariants, BA.2 and BA.3, and reported them to the global database weeks before they were reported elsewhere, demonstrating that the program is able to detect variants early," the CDC said.
