China to stop using Covid-19 anal swabs for all foreign arrivals in airports, claiming the invasive tests are "humiliating".The procedure involves an eye-wateringly long cotton swab of 5cm up the rectum, which the Chinese government claims to be more precise than the PCR (polymerase chain reaction) tests carried out using the nose and throat.As part of the new travel requirement, there will be testing hubs in Beijing and Shanghai airports, the Times reports.Some Chinese cities have used anal samples to detect potential coronavirus infections during a recent spate of regional outbreaks.Li Tongzeng, a respiratory disease doctor, told state media that Covid traces stay detectable for longer in the rectum than they do in the nose or.