The Centre for Health Protection (CHP) said the 41-year-old woman, who tested preliminary positive on Wednesday and confirmed with the L452R strain on the following day, has twice tested negative for Covid-19 after being hospitalised. She’s also tested negative for antibodies.
The CHP’s Dr Chuang Shuk-kwan said the woman works as a cleaner at the Bridal Tea house Hotel in Yau Ma Tei – a designated quarantine facility – and had on Wednesday cleaned the room of an Indonesian woman who’d earlier been confirmed to be infected with the L452R mutated strain.
She subsequently went to take a test at a nearby testing centre, where her sample came back positive.
Chuang said officials are trying to establish why she’s no longer testing positive for the virus, adding it’s too early to conclude whether this could be a false-positive case.
“We find it a bit strange that the patient [originally] tested positive and then repeatedly negative with a negative serology. Of course there may be explanation such as she’s at a very early stage after infecting the virus and she’s still incubating the virus. So after a few days repeated testing may give a positive result,” she said.
Chuang added that experts are at the Bridal Tea House Hotel to find out whether environmental contamination could be a possibility.
“We are wondering whether there is a possibility of, for example, environmental contamination. If the virus is not a live virus … she’s not actually infected but carried the virus in her nasal pathway especially when she almost immediately take the swab after she cleaned the room.”
University of Hong Kong microbiologist Yuen Kwok-yung also said it’s possible that the 41-year-old cleaner had caught the virus from cleaning the affected hotel room.
Speaking to reporters after inspecting the Bridal Tea House hotel, Yuen said the room had been disinfected by a contractor before being cleaned by the woman.
However, he said the contractor only spent less than ten minutes to disinfect the room and did not use a proper disinfectant recommended by the Centre for Health Protection.
The “far from ideal arrangement”, he said, may have allowed the virus to remain in the room.
Yuen urged cleaners who work at designated hotels to get vaccinated, and called on cleaning contractors to strictly adhere to the disinfection guidelines laid down by Centre for Health Protection.
Meanwhile, there are also 10 new imported cases, involving people who flew in from the UK, Indonesia, and Russia. Nine of the patients carried the L452R strain.
As mutated variants of the coronavirus continue to spread around the globe, both Yuen and Chuang once again urged people to get vaccinated as soon as possible.
Last updated: 2021-07-02 HKT 18:42