Coronavirus found in air samples up to 4 metres from patients: China study

[KY_EnviroGuy]

Coronavirus found in air samples up to 4 metres from patients: China study
11 Apr 2020 11:57AM (Updated: 11 Apr 2020 12:05PM)
Original source: AFP

Link: https://www.channelnewsasia.com/news/asia/coronavirus-airborne-4-metres-patients-covid-19-china-study-12632608

(snips)

WASHINGTON: A new study examining air samples from hospital wards with COVID-19 patients has found the virus can travel up to 4m – twice the distance current guidelines say people should leave between themselves in public. The preliminary results of the investigation by Chinese researchers were published on Friday in Emerging Infectious Diseases, a journal of the US Centers for Disease Control and Prevention (CDC).

They add to a growing debate on how the disease is transmitted, with the scientists themselves cautioning that the small quantities of virus they found at this distance are not necessarily infectious. The researchers, led by a team at the Academy of Military Medical Sciences in Beijing, tested surface and air samples from an intensive care unit and a general COVID-19 ward at Huoshenshan Hospital in Wuhan. They housed a total of 24 patients between Feb 19 and Mar 2.

The team also looked at so-called aerosol transmission - when the droplets of the virus are so fine they become suspended and remain airborne for several hours, unlike cough or sneeze droplets that fall to the ground within seconds. They found that virus-laden aerosols were mainly concentrated near and downstream from patients at up to 4m – though smaller quantities were found upstream, up to 2.4m.

They also offered advice that bucks orthodox guidelines: "Our findings suggest that home isolation of persons with suspected COVID-19 might not be a good control strategy" given the levels of environmental contamination. Aerosolisation of the coronavirus is a contentious area for scientists who study it, because it is not clear how infectious the disease is in the tiny quantities found in ultrafine mist.

(4-meters approx. equals 13-feet)

This suggests some droplets become aerosolized after traveling some distance, perhaps from vaporization, depending on ambient temperature and humidity and air movement in the space.

The article goes on to describe their findings on contamination of surfaces such as floors and frequently touched surfaces like computer mice, rubbish bins, bed rails and doorknobs. They also discuss contamination found on hospital worker's shoes.

(cross-posted to GD)


KY............

[Delarage]

1. Masks

That's why I'm wearing a mask when I go out, although the scientists weren't sure how infectious what remained of the virus at 4 meters was. I believe viral load matters as well, from other things I've read (the amount of virus you're exposed to). I try to stay as far away from people as possible anyway---crossing the street to avoid passing others, etc.

But this is scary stuff.

[KY_EnviroGuy]

2. This article is very informative and probably represents a worst case....

unless you encounter an infected person close-up.

Coronavirus can travel twice as far as official ‘safe distance’ and stay in air for 30 minutes, Chinese study finds

Authorities advise people to stay 1-2 metres apart, but researchers found that a bus passenger infected fellow travelers sitting 4.5 metres away.

The scientists behind the research said their investigation also highlighted the importance of wearing face masks because of the length of time it can linger.

Link: https://www.scmp.com/news/china/science/article/3074351/coronavirus-can-travel-twice-far-official-safe-distance-and-stay

Keep in mind the people on that bus were there for four hours. However, it is indicative of the risks of being in the same home or apartment with an infected person.

Yes it's scary as hell, especially for those of use that are high-risk.