How is Covid-19 spread?

According to UKHSA health and security agency guidance, Reducing the spread of respiratory infections, including Covid-19, in the workplace:

“When someone with an infection breathes, speaks, coughs or sneezes, they release respiratory particles which can contain the virus. These particles can come into contact with the eyes, nose or mouth or can be breathed in by another person. These virus-containing particles can also land on surfaces and the virus can be passed from person to person via touch. In general, the risk of catching or passing on a respiratory infection is highest when in close contact with someone who is infected.”

It adds: “It is also possible to pass on a respiratory infection between people who do not have close contact, especially if they are in a crowded and/or poorly ventilated space where smaller virus particles can stay suspended in the air for some time and where there are more people who might be infectious.”

The risk of airborne transmission increases when occupants in a space are participating in energetic activity, such as exercising, shouting, singing or talking loudly. Safety campaigners point out that official UK and international bodies were slow to recognise the risk of airborne transmission. TUC advice, issued in January 2021, makes clear that: “The main way the virus spreads is airborne transmission — i.e. breathing in the air of an infected person.”