Spoiler alert: Doctor reveals the one simple trick that could spare you getting sick while flying

The next time you think about turning off the overhead vent above you on an airplane, you may want to reconsider. 

Experts told DailyMail.com that keeping the vents, also known as air gaspers, on could help you avoid contact with certain germs and cut your risk of getting sick in half. 

Airplanes have some of the most sophisticated ventilation systems in the world and protect you from getting sick while flying.

This is especially valuable during cold and flu season, where the cramped conditions on many commercial flights can be a hotbed for infections.

‘A lot of people don’t take advantage of it, but what that does it that provides you with a little more air turbulence in your area that you’re sitting in,’ Dr Mark Gendreau, chief medical officer at Beth Israel Lahey Health, Beverly Hospital, told DailyMail.com. 

‘If there is a viral particle coming your way, theoretically it can push that and move it quickly out of your space.’ 

On their own, airplane ventilation systems filter out the vast majority of airborne particles. 

Planes use high-efficiency particulate air, or HEPA, filters to remove 99.97 percent of dust, pollen, mold, bacteria, and airborne particles, according to the US Environmental Protection Agency (EPA). 

‘Airlines are very motivated to keep this well functioning. Because when it’s not functioning well, it basically causes a lot of drag, and they burn a lot of fuel as a result, Dr Gendreau, an expert on infectious diseases associated with air travel, said. 

The ventilation system on the aircraft is actually equal to, or slightly better than, most operating rooms and hospitals throughout the world.’

Dr Mark Gendreau, chief medical officer at Beverly Hospital in Beverly Massachusetts, and expert on infectious diseases on airplanes, recommended turning on the air gaspers above you to keep from getting sick. He also said not to crowd the aisle and to stay hydrated

This is because they get anywhere from 15 to 30 air changes per hour, with 50 percent of the air being recirculated and the other half coming from outside the plane. 

Even if an airline changes the filters less often than recommended, they will still trap the majority of particles, according to the International Air Transport Association. 

From your seat on the plane, the above ventilation serves several rows in front of and behind you. 

However, HEPA filters can’t catch everything. 

Airborne viruses, such as Covid, can travel several feet and become suspended in the air. 

The EPA estimates they can linger for hours in some cases, even after someone has already left the space. This makes you much more likely to come in contact with them. 

Dr Gendreau said that if you’re several rows away from someone who has Covid, the risk is fairly low. 

‘If you’re seated within two seats from a person, there’s some risk there, but it’s not as high as you would think,’ he said. 

Air gaspers may help close some of those gaps.

‘With a HEPA filter and all the fresh air, that risk of that viral particle being an issue is gone,’ Dr Gendreau said. 

Turning on your gasper may benefit the person sitting next to you as well, but they can’t reach much further than that. If you’re sitting by the window, for example, someone in the aisle seat would need to turn on their own gasper.

However, you don’t need to turn it on at full blast directly in your face, Dr Gendreau said. He suggested adjusting the air-flow to what feels most comfortable for you. 

‘It doesn’t need to be pointed at you. It just needs to be pointed a little bit in front of you and down,’ Dr Gendreau said. 

However, turning on a bit of extra air isn’t the only thing you can do to lower your risk. 

Crowding the aisles after the plane lands can be a major risk.

This is because after landing, there’s a brief period of time when the pilot shuts off the aircraft’s ventilation system before crews turn on the plane’s auxiliary power unit.  

‘If you’re crowding the aisle and you’re super close to everybody, you’re just putting yourself at a significant risk,’ Dr Gendreau said. 

Additionally, drinking too many caffeinated beverages could leave you dehydrated. Because immune cells need water to eliminate toxins and waste, not getting enough water leaves them vulnerable. 

Dr Gendreau suggested skipping coffee and alcohol and instead opting for water to avoid this. 

Though air gaspers and HEPA filters can eliminate most airborne particles, there’s still the risk of picking up germs on surfaces, such as opening the overhead bins or touching the seats. 

Dr Gendreau said that 70 to 80 percent of all infections are transmitted through your hands, and most of us make that worse by touching our eyes, nose, and mouth up to 20 times an hour. 

He recommends bringing hand sanitizer on-board, and also washing your hands to mitigate risk.