By Cassidy Morrison Senior Health Reporter For Dailymail.Com
22:37 01 May 2024, updated 22:40 01 May 2024
- New WHO report said cold and flu viruses spread through air, not on surfaces
- The guidance means mitigation measures like handwashing are not as effective
- READ MORE: CDC says coronavirus DOES spread through the air
Sharing glasses and bottles of water with a sick friend or family member may not infect you with the common cold virus after all, World Health Organization experts have suggested in a landmark report.
New guidance by a coalition of nearly 50 doctors overturned the commonly believed idea that infected droplets transferred from hard surfaces and skin are the cause of respiratory viruses like colds and flu.
The decision settled a Covid-era debate about whether some viruses like Covid spread mostly through inhaling infected air, or from contaminated surfaces.
Speaking to DailyMail.com, experts in virology welcomed the conclusion that surfaces are not as vital as previously thought, which they say should have been confirmed early on in the pandemic.
Dr Don Milton, an expert on respiratory viruses and co-author of the new WHO guidance, told DailyMail.com: We know that for gastrointestinal infections [hand washing and being careful touching surfaces like cups] are going to be important.
‘How important they are for respiratory viruses, I think is probably a lot less.’
The WHO guidance applied to all pathogens that cause lung infections, including Covid, influenza, and rhinovirus.
The report did not include non-respiratory infections, such as GI infections like norovirus, which can be spread via germs on the hands.
Until late 2020, the WHO had only considered a few infections as airborne, such as tuberculosis and measles. Most of them were classified as ‘droplet transmission’.
Covid was classified the same way at first. That messaging prompted millions of people in early 2020 to disinfect every surface, including groceries and mail. This even drove a shortage of cleaning supplies at the time.
But evidence grew that Covid could be transmitted via aerosolized particles. Suspended particles can remain in the air for hours, casting a pathogenic cloud over an infected person that follows them wherever they go.
Dr Stuart Ray, an infectious diseases expert at Johns Hopkins Medicine, told DailyMail.com: ‘I think the lessons from Covid helped us understand that that cloud of particles can move,’ adding that people should still wash their hands to be safe.
The longstanding dogma among infectious disease experts was that droplets under five microns were airborne while droplets that were larger shot out like bullets and spread three to six feet.
But scientists have recently discovered that infectious particles come in a range of sizes, and tiny particles can remain in the air for far longer and spread longer distances.
The report came after doctors across a range of specialties in addition to virology, including engineers and aerosol scientists, worked for two long years to reach a conclusion. Dr Milton, who has long thought respiratory viruses spread through the air, found the delay frustrating.
He said: ‘When we showed that we could culture the virus from people’s exhaled breath [in 2013] I thought we were going to get over the hill at that point, but clearly there are still a ways to go.
‘Some of that resistance is because some of the solutions require investment in infrastructure and require people to do things, and those are two hard things to do – put money up and change what you do.’
Sarah Carter is a health and wellness expert residing in the UK. With a background in healthcare, she offers evidence-based advice on fitness, nutrition, and mental well-being, promoting healthier living for readers.