Hong Kong health officials on Tuesday evacuated residents from a high-rise apartment building called Hong Mei House because at least five of the city’s 42 confirmed cases of the Wuhan coronavirus have been linked to the building.
The authorities believe the virus may have spread through poorly-designed toilets and bathroom pipes in the public housing project.
The South China Morning Post (SCMP) described the plumbing problem:
A Housing Department policy change has allowed tenants in government flats to alter the pipe design in their bathrooms since 2016, a problem which might have helped the faster spread of the deadly new coronavirus which led to an evacuation of a Tsing Yi housing block on Tuesday, the Post has found.
Opened to residents in 1986, Hong Mei House is one of 13 blocks of flats on the Cheung Hong Estate. The 35-storey building is made up of 840 units in three wings, dubbed a Y2 design.
According to the original design of the bathroom, the toilet is located in the centre of the unit, with all outlets, including the waste pipe and vent pipe exposed and connected with the bowl.
Health officials evacuated over 30 units that had piping systems similar to those in the apartments of a 62-year-old woman and 75-year-old man who became infected. The two infected residents lived ten floors apart, but the virus may have spread between their apartments through the piping system.
The problem, as Housing Minister Frank Chan-fan explained, is that many residents have altered the safe but ungainly piping arrangement in their bathrooms, creating unsafe situations where “foul air” can spread between units because the vent pipes have been retrofitted or disconnected entirely. Newer apartments have their bathroom pipes discreetly hidden inside the walls, so the residents are not likely to modify them.
Such alterations were not permitted for public housing tenants until the revised guidelines were issued in 2016. The SCMP cited speculation that the rules were changed mainly to relieve some of the burden on the housing department, which lacked the manpower to perform all the inspections needed under the older, stricter guidelines.
Chan-fan stressed that the coronavirus did not spread through water pipes and toilets, but rather through air vent pipes bundled into the plumbing system. This clarification was important because the 2003 SARS epidemic was known to spread through faulty plumbing.
Medical researchers are still working to determine how the Wuhan virus spreads. Although direct human contact is normally thought to be necessary, Hong Kong doctors suggested the virus might have passed between the two Hong Mei House apartments when infected fecal matter passed into the altered ventilation system.
CNN reported on Wednesday that the son of the infected 62-year-old woman, his wife, and his wife’s father have all been diagnosed with the coronavirus.
“While the investigation into the building continues, Hong Kong’s Center for Health Protection has advised the public to maintain drainage pipes by regularly pouring water into drain outlets – the U-pipes – and to put the toilet lid down before flushing ‘to avoid spreading germs,’” CNN added.
The SCMP ominously noted that “similar pipe designs can be found in 48 other public housing estates in the city.”