U.S. diplomats in China were subjected to anal swab tests for Covid-19, a Department of State spokesperson confirmed Thursday, adding that a protest had been lodged with the Chinese Ministry of Foreign Affairs.
The United States had received assurances from China that the tests were done in error and that diplomatic personnel were exempt from this specific testing requirement, the spokesperson said.
"The Department is committed to guaranteeing the safety and security of American diplomats and their families while preserving their dignity, consistent with the Vienna Convention on Diplomatic Relations, as well as other relevant diplomatic law provisions," the spokesperson said.
The story was first reported by The Washington Post.
However, Zhao Lijian, a spokesman for the Chinese Ministry of Foreign Affairs, told a news conference Thursday that he had checked with his colleagues and as far as he knew, "China has never asked U.S. diplomats stationed in China to have anal swab tests."
Anal swabs could be more effective because traces of the virus stay in fecal matter for a longer time than those in the respiratory tract, Dr. Li Tongzeng, a respiratory diseases doctor in Beijing, told Chinese state television last month.
Ahead of the Lunar New Year holidays earlier this month, some Chinese cities used anal swab samples on people to detect potential infections during stepped-up screenings, after a spate of regional outbreaks.
In mainland China, 89,864 Covid-19 cases have been confirmed since the outbreak began, while the death toll has remained unchanged for some time at 4,636 people, according to data from the country's National Health Commission.
Relations between China and the U.S. grew tense under former President Donald Trump who criticized the world's second largest economy over trade, the outbreak of the pandemic, Beijing's treatment of Hong Kong protesters and its Uighur Muslim minority.
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On Wednesday, President Joe Biden's nominee to be director of the CIA, former ambassador William Burns, 64, told a Senate committee he saw competition with China — and countering its "adversarial, predatory" leadership — as the key to U.S. national security.
The White House said in a statement at the time that Biden had raised "fundamental concerns" about Beijing's "coercive and unfair economic practices, crackdown in Hong Kong, human rights abuses in Xinjiang, and increasingly assertive actions in the region, including toward Taiwan."
Reuters contributed to this report.