A 62-year-old girl was identified with the virus a couple of week-and-a-half after a 75-year-old man in the identical constructing grew to become contaminated.
Three extra circumstances have since been linked to Hong Mei Home. The girl’s son, his spouse and her father have been identified with the virus. The mom, son and spouse share an condo.
The 2 preliminary circumstances set off alarm bells amongst well being officers that the virus might have been transmitted by means of pipes within the constructing. In densely populated Hong Kong this might result in a whole bunch of individuals turning into contaminated within the supposed security of their very own properties.
In Hong Mei Home, the 2 preliminary sufferers with coronavirus lived 10 flooring aside, however have been on the identical vertical block of flats — quantity seven. Well being authorities evacuated residents residing in flats numbered seven on all 30 flooring of the constructing as a result of their rest room discharge pipes have been linked.
An investigation was launched Tuesday, however officers have been fast to defend the constructing’s sewage system as secure. As a substitute, Hong Kong housing minister Frank Chan mentioned at a press convention that an preliminary investigation probably pointed to a rest room pipe of the second affected person that would have been altered.
The Hong Kong authorities additionally posted a photograph on social media exhibiting that a pipe within the condo’s rest room had been altered.
However might this have led to a potential unfold of the virus?
The evacuation at Hong Mei Home was a precaution.
Whereas scientists are nonetheless investigating how the virus spreads, they consider it’s primarily transmitted by direct contact, reminiscent of touching somebody’s hand, and thru droplets, for instance, an contaminated individual sneezing or coughing on another person.
Subsequently, the virus might have unfold by means of the condo block by means of shut human contact or the shared use of elevator buttons.
However as a result of the 2 sufferers lived straight above each other, and the preliminary inspection discovered that a pipe had been disconnected from the lavatory’s waste pipe, authorities determined to research whether or not the virus might have unfold by means of the constructing’s sewage system.
Microbiologist Yuen Kwok-yung mentioned at a Tuesday press convention that an improperly sealed pipe might have resulted in a virus transmission, by carrying contaminated feces into the constructing’s air flow system and blowing it into folks’s bogs.
“Because the pipeline that transfers feces is linked to the air pipe, it is rather probably for the virus within the feces to be transmitted by means of the air fan into the bathroom,” Yuen mentioned.
So how does this work?
Each rest room, sink, and ground drain has a U-shaped pipe, which prevents sewer gases from getting into the house and permits waste water and odors to flee. To work correctly the U-shaped pipe, often known as a U-trap, wants to carry water in its bend.
These pipes hook up with what’s referred to as a soil pipe, often known as a discharge pipe, which washes the waste away from the bathroom, sink or drain.
The soil pipe must have a vent pipe linked, which ensures the sewer gases and odors are carried away — often by means of a vent within the roof. The vent pipe additionally makes certain that stress within the drain is equalized so waste water retains flowing.
“In the event you think about the pipe linking all of the bogs in the identical unit on completely different flooring — it is like a Christmas tree,” mentioned Hung.
“When the U-shaped pipe was not crammed with water, the air within the discharge pipe of the lavatory can enter the indoor atmosphere. Particularly as soon as the extraction fan within the rest room is turned on,” mentioned Yuen.
Hong Kong officers have mentioned Hong Mei Home is completely different from the SARS situation, nonetheless, due to the design of the pipes ensures water is at all times within the U-bend.
Tse Chin-Wan, undersecretary for the Hong Kong Surroundings Bureau, mentioned on Tuesday that the pipes in Hong Mei Home weren’t defective.
Not like at Amoy Gardens, their ground drains have been linked to the sink of kitchens or washing basin, which means the U-bends have been at all times full with water.
Ivan Hung, chief of the Infectious Ailments Division at Hong Kong College, informed CNN the SARS case was “very completely different and far more severe” owing to a extremely infectious affected person and the virus being airborne.
As many as two-thirds of the sufferers within the Amoy Gardens outbreak had diarrhea, and that meant a big viral load — the amount of virus — would have been discharged into the defective drainage system.
However how can others get contaminated?
In Hong Mei Home, authorities are nonetheless investigating a modified vent pipe that would have allowed the virus to unfold.
“There are causes to consider that confirmed circumstances of low-level models are brought on by improper modification of bathroom exhaust pipe,” Leung Kar-ming, the district councilor representing Hong Mei Home, informed CNN in an e mail.
“It’s to (be) believed at this stage it is because of improper modification of particular person unit (307) the place components of the pipe have been lower off and eliminated completely.”
One risk is that contaminated materials from the primary affected person’s condo might have traveled down the pipes and entered the room by way of the damaged vent within the second affected person’s rest room.
“If the affected person is in the bathroom and studying a newspaper, or no matter he is doing, then he shall be uncovered to this contaminated air,” mentioned Hung.
Whereas the investigation into the constructing continues, Hong Kong’s Heart for Well being Safety has suggested the general public to keep up drainage pipes by recurrently pouring water into drain retailers — the U-pipes — and to place the bathroom lid down earlier than flushing “to keep away from spreading germs.”
If it does emerge that the virus can journey by means of pipes, it would imply that residents staying at dwelling to keep away from the virus may be in danger within the place they felt most secure.
CNN’s Eric Cheung, Vanessa Yung, Alexandra Lin and James Griffiths contributed to reporting.