Coronavirus cases in the Americas have surged 27.2 per cent in a week, driven primarily by a spike in infections in the United States, the Pan American Health Organisation says, while China has removed certain COVID-19 test requirements for people flying in from overseas.
PAHO said more than half of a total 918,000 infections came from North America as US cases jumped by 33 per cent to 605,000 in the last week.
Infections in North America have now been climbing for the past seven weeks, it said.
PAHO Director Dr Carissa Etienne noted that many countries and local governments are abandoning masking and distancing requirements and have reopened borders after a period of lower transmission.
However, too many people remain at risk as only 14 of the 51 countries and territories in the Americas have reached the World Health Organisation's goal of vaccinating 70 per cent of their population, she added during a news conference.
PAHO said new COVID-19 infections and deaths in the region have been rising steadily over the past four weeks, with more than 3500 fatalities reported last week.
"It is time to take stock of these numbers and act. COVID is again on the rise in the Americas," Etienne said.
"The truth is this virus is not going away anytime soon."
Meanwhile, China has removed certain COVID-19 test requirements for people flying in from countries like the US and shortened the pre-departure quarantine period for some inbound travellers.
The slight relaxations were made in response to factors including the "characteristics of coronavirus variants," according to notices from Chinese embassies and consulates that did not provide further details.
From Friday, travellers from Dallas, New York, Los Angeles, San Francesco and Seattle will no longer need an RT-PCR test seven days before they fly, or any antibody tests, according to notices issued late on Tuesday from the Chinese embassy in the United States and several consulates.
Those travellers will still need to do two RT-PCR tests within 48 or 24 hours of their flights - depending on which airport they are flying out of - plus another pre-flight antigen test, those notices showed.
Travel into and out of China has plunged during outbreaks of COVID-19 as the country insists on its "dynamic COVID zero" playbook that has involved restrictions on the issue and renewal of passports, mandatory quarantines for most travellers upon arrival and flight cancellations.
But the shorter incubation period of the Omicron variant has allowed for a slight easing of curbs on international travellers.
The capital city Beijing said earlier this month it had reduced the quarantine period at centralised facilities upon arrival for travellers to 10 days from 14 days, although another week of at-home isolation remains in place.
Embassies in the United Arab Emirates, Serbia and Bangladesh said on Wednesday they had removed antibody test requirements for travellers to China, and that those who had recovered from COVID-19 infection no longer needed to provide chest scan images.
Australian Associated Press
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