By Amy Cheng
Two coronavirus cases recently identified at a Hong Kong quarantine hotel are "very likely to be epidemiologically linked," local public health authorities said, leading a medical expert to slam face masks with breathing valves as "selfish."
Following a public health investigation, which included an inspection of the Regal Airport Hotel where the two travellers were quarantining, Yuen Kwok-yung, a leading microbiologist at the University of Hong Kong, said Monday that one of the two infected guests used a valve-equipped face mask when he opened his hotel door to retrieve delivered meals and deposit trash, and was maskless at times.
Yuen, who advises the Hong Kong government on Covid policies, went on to call valve-equipped face coverings "selfish," explaining that these vented designs "filter air when inhaling, but when the air is breathed out through the air valve, it is not filtered, which is not good," the South China Morning Post reported.
A 36-year-old male guest at the hotel, who arrived from South Africa on Nov. 11, tested positive for the coronavirus two days later. According to the Hong Kong health department, he apparently opened his hotel room sometimes without a proper surgical mask. This may have allowed virus-carrying particles to enter the hotel corridor, which the department said also had "unsatisfactory" air flow.
On November 18, the 62-year-old guest staying across the hallway, who had arrived from Canada, was diagnosed with the same mutant strain of the virus, a strong indication that the two patients may be epidemiologically connected.
Most travellers have to undergo two to three weeks of quarantine at a government-appointed facility upon their arrival in the international financial hub. As other countries in Southeast Asia begin to reopen their borders, Hong Kong authorities have steadfastly stuck to strict quarantine measures and prioritised efforts to establish a quarantine-free travel agreement with mainland China.
The Regal Airport Hotel did not respond to questions on Wednesday morning about how it enforces mask-wearing requirements for guests in mandatory quarantine, or what measures it plans to take in the future to prevent cross-infection.
The hotel has promised that all staff would wear masks at all times. The Hong Kong government also asks that all hotel quarantine guests wear masks when they open their room doors, but hasn't publicly specified any punishment for violations.
The company 3M, which designs valve-equipped masks for construction work, says these face coverings allow for easier breathing as wearers take part in physically demanding tasks in "hot or humid" conditions.
The US Centers for Disease Control and Prevention has warned against wearing face masks with exhalation valves or vents, saying they can allow virus particles to escape, and some major airlines have banned them.