Covid-19 testing requirements for passengers traveling from China highlight mounting concerns about the potential for undetected new strains of the virus spawned by the country’s burgeoning outbreak.
When the US imposed requirements for travelers from China to show negative test results, it also expanded a program that collects voluntary samples from international passengers at airports to help monitor variants entering the country. On Friday, the UK and France joined the rush of countries testing passengers and sequencing samples from people arriving from China in an effort to identify any dangerous new mutations that could spread rapidly through their populations.
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