China has begun deploying anal swab tests to detect severe COVID-19 cases in select groups, as cases started to rise again ahead of the upcoming Lunar New Year.
The procedure, deemed “humiliating” by some residents, was already tested in small groups last year. However, a study conducted by Chinese researchers and published in the Future Microbiology journal in August states that the anal tests generated more accurate results than the throat swabs. It was confirmed after some patients recovering from the disease tested positive in anal swab samples after they tested negative in the throat swab.
“Intriguingly, SARS-CoV-2 detection was positive in the anal swab of two patients and negative in throat swab and sputum samples,” they wrote. “We propose anal swabs as the potentially optimal specimen for SARS-CoV-2 detection for evaluation of hospital discharge of covid-19 patients.”
Meanwhile, Beijing's You'an Hospital’s infectious disease specialist Li Tongzeng told state broadcaster CCTV that the anal swabs method "can increase the detection rate of infected people" as traces of the virus linger longer in the anus than in the respiratory tract.
This year, the Chinese government has approved the expanded use of anal swab testing to contain the continuing increase of positive cases ahead of the Lunar New Year.
According to Washington Post, 3 billion trips are made over the holiday before the pandemic. Now, authorities are speeding up testing with a target of 50 million people by the Lunar New Year scheduled on Feb. 12.
The Chinese Center for Disease Control and Prevention said that initially, testing could be done by collecting stool samples from the patients. If that would not be possible, the anal swab test will be conducted by inserting a cotton-tipped stick one to two inches into the rectum.
However, some doctors remain skeptical about the accuracy of the test, saying that nasal and throat swabs are still more effective because COVID-19 is a respiratory infection.
“There have been cases concerning the coronavirus testing positive in a patient’s excrement, but no evidence has suggested it had been transmitted through one’s digestive system,” Wuhan University pathologist Yang Zhanqiu told state tabloid Global Times.
Dr. Tongzeng, on the other hand, told CCTV that while the anal swab test could hasten the detection of COVID-19 among Chinese, it will not be used as widely as other methods because it is “not convenient.”
“Considering that collecting anal swabs is not as convenient as throat swabs, at the moment only key groups such as those in quarantine receive both,” he said.
Despite that, users of China’s popular social media platform Weibo took the news with hilarity and horror.
"So lucky I returned to China earlier," one user wrote. "Low harm, but extreme humiliation," another remarked with a laughing emoji.
Even those who took the anal test chimed in. "I've done two anal swabs, every time I did one I had to do a throat swab afterwards—I was so scared the nurse would forget to use a new swab," one Weibo user joked.