Health authorities said on Saturday that they are investigating how another aircraft cleaner might have caught Covid-19, after the woman tested preliminary positive for the virus.
The 41-year-old lives in Tsing Yi and is in charge of cleaning facilities on cargo flights, such as the front of the aircraft, kitchens and toilets. Just last week, a 39-year-old aircraft cabin cleaner was found to be infected.
Health officials said they will carry out genome sequencing to check if the 41-year-old, who says she stayed away from crew members even if she sees them during work, is linked to previous cases.
"She may have met pilots or other people in that setting, and because those people didn't need to enter Hong Kong’s borders and didn't get tested, we don't know if they are infected. This situation is more likely due to human interaction, but of course environmental contamination is also possible," said Dr Chuang Shuk-kwan of the Centre for Health Protection (CHP).
"But I think the chance of her getting infected in the community is relatively lower... because after all, she has a high-risk job," Chuang added.
Officials said they will also check which aircraft the woman cleaned and where they flew in from. Several of the woman's colleagues will be quarantined.
Chuang said infection control training would also be stepped up for people who have high-risk jobs.
"We need to step up the infection control training for them to make sure they gown and degown the [personal protective equipment] with proper procedures," she said.
Another preliminary positive case is linked to a previous patient, and there are around ten preliminary positive infections for the day.
In all, the CHP reported five confirmed coronavirus cases on Saturday, including two local cases that are linked to previous infections.