According to news reports, travelers to some Chinese cities have been forced to take anal swab tests for COVID-19, a measure that has sparked calls from other countries.
This week, officials in Japan complained that some Japanese citizens arriving in China were subjected to the tests, which ’cause great psychological pain’. according to the BBC.
And in February, some U.S. diplomats said they had to take the tests, which led to a complaint from the U.S. Department of State. View report.
“The State Department never agreed to these types of tests and protested directly against the Ministry of Foreign Affairs when we heard that some staff were subject to it,” a State Department spokesman told Vice. (Chinese officials have denied that US diplomats are being asked to undergo anal tests, reports Vice.)
It is unclear how many international travelers had to take the anal tests, but according to reports, Beijing and Shanghai had to require the tests for some arrivals. The New York Times.
Some Chinese doctors say tests are being carried out to catch silent carriers of the virus – those who may not show symptoms or who develop mild symptoms but recover quickly – because the new coronavirus can be detected in feces longer than in the nose. and throat.
“Some asymptomatic patients or those with mild symptoms recover quickly [from COVID-19], and it is possible that throat tests will not be effective for these people, ‘Li Tongzeng, a doctor in infectious diseases in China, told CNN.
“Researchers have shown that the duration of positive nuclei results for some infected people was longer during their bowel movements and anal swab test. [samples] than those in the upper airways. Therefore, the addition of anal swab tests can improve the positive detection rate of the infected, ‘he said, referring to the so-called PCR diagnostic tests for the virus.
Some Chinese citizens also have to do COIVD-19 anal tests. In January, more than 1,000 students and teachers in a Beijing school district received anal swab tests, as well as nasal swab tests, for COVID-19 after a 9-year-old student in the district tested positive, according to vice. Other people staying in quarantine hotels were asked to take the tests. One person told Vice that he was asked in September 2020 to take an anal test while in a quarantine hotel after returning from Australia. He said the test was administered by nurses and that it ‘feels like he has diarrhea’, Vice reported.
The tests were controversial even among experts in China. Yang Zhanqiu, deputy director of the division of pathogen biology at Wuhan University, told the state-run Chinese newspaper Global Times in January, nose and throat tests were still more effective than anal tests because the virus is known by respiratory drops rather than by feces. If the point of the tests is to prevent an infected person from spreading the virus, then the argument performs the nose / throat tests best.
“There have been cases involving the coronavirus that were positive in a patient’s feces, but no evidence indicated that it was transmitted through the digestive system,” Yang said.
Experts outside China are also questioning the practice, as those who test positive for COVID-19 on an anal test but not on a nose or throat test are unlikely to be highly contagious, according to The New York Times.
“The value of detecting people with the virus is to stop the transmission,” Benjamin Cowling, a professor of public health at the University of Hong Kong, told the Times. “If someone has an infection but no one else is infected, we do not need to detect the person.”
Originally published on Live Science.