Every Monday, we’ll answer your questions on Covid-19 and health in a feature published online. You can submit a question here.
This week, HuffPost UK reader Janet asked: “If I hold my breath when I walk past people, would that help stop me getting coronavirus if they have it?”
Many of us have been there: walking along the path, staring at your shoes, when you look up and notice someone is about to walk right past you. You haven’t got time to cross the road. You briefly panic as you’re not wearing your face mask and there’s not enough room to keep two metres apart.
As you near each other, you realise they’re talking on their phone. They cough once. (Or were they just clearing their throat?)
There’s nothing for it: you hold your breath and sail right past them. After a few seconds, you release your breath. Phew.
Since coronavirus landed on UK shores, breath-holding has become an activity that some of us do almost absent-mindedly. But can holding your breath as you walk past a stranger actually prevent you from catching coronavirus if they happen to have it? Or is it more of a coping mechanism?
“The risk of transmission when you just cross someone in the street is very low, especially if you’re wearing a good mask,” says Professor Jose-Luis Jimenez, an aerosol expert from the University of Colorado Boulder.
That said, holding your breath when you cross someone “might help a little bit in some very infrequent circumstances”, he says. For example, if you cross someone who is shedding a high viral load into aerosols, and their exhaled breath happens to go your way with little dilution.
Prof Jimenez admits he has held his breath when passing people in the street before. So, too, has Dr Julian Tang, honorary associate professor and a clinical virologist from the University of Leicester. “I used to do this in the early pandemic – and other people have done the same thing,” he tells HuffPost UK.
Dr Tang recommends that if you see someone walking towards you, it’s best to take a quick breath in and then you exhale out after you’ve walked past them.
“Holding your breath is good but if you breathe out, it’s even better, because you then blow any virus away,” he says.
Dr Tang likens it to swimming – you take a big breath, hold, and swim under water. Then when you come up for air, you breathe out. “It’s a physically robust way of avoiding inhaling any aerosols,” he says.
While most experts agree that the risk of catching the virus outdoors is pretty low – and studies back this up – Prof Tang is of the mind that every little helps.
“If you consider the other modes of transmission: you don’t touch people as you walk past them, and large droplets will fall to the ground anyway – you won’t even inhale them because they’re so big,” he notes.
“So the aerosol transmission is how we think this virus really spreads. And if you want to control that inhalation risk, either holding your breath or even breathing out – if you can time it right as you walk past them – will add to that protection of being outdoors.”
Experts are still learning about Covid-19. The information in this story is what was known or available at the time of publication, but guidance could change as scientists discover more about the virus. To keep up to date with health advice and cases in your area, visit gov.uk/coronavirus and nhs.uk.