top of page

How are viruses transmitted through the air?

Updated: Jan 29, 2021

Is flying in this COVID-19 era still safe for you? Is it true that the air quality in aircraft cabins are much better than in a restaurant?

Lets find out on how viruses are transmitted through the air and whether is it still safe to fly now if there were no restrictions on travelling.

Airborne diseases

One can catch some diseases simply by breathing and these is called airborne diseases. Airborne transmission occurs by dissemination of suspended particles or pathogens less than five micrometres in diameter through the air.


These particles can be bacteria, fungi or even viruses. These suspended particles or pathogens are primarily formed when a person coughs, sneezes or talks. When these particles are propelled a short distance (within one metre) through the air from one individual and is deposited on the host’s mucous membranes, airborne transmission has taken place.

Airborne disease can spread when people with certain infections cough, sneeze, or talk, spewing nasal, and throat secretions into the air. Some viruses or bacteria take flight and hang in the air or land on other people or surfaces. Because these diseases travel in the air, they are typically harder to control.

Types of airborne diseases

Particles or pathogens that cause airborne diseases are small enough to cling on to the air. It will hang on to dust particles, moisture droplets, or even on the breath until they are picked up. They can also be acquired through contact with body fluids, such as phlegm. Once these pathogens are inside the body, they will multiply until someone has the disease. Common airborne diseases include:

  • Coronavirus and COVID-19

A rapidly spreading coronavirus, SARS-CoV-2, and the disease it causes which is COVID-19, has been responsible for millions of infections and hundreds of thousand of deaths globally in 2020. Although the coronavirus that causes COVID-19 is not generally considered to be airborne, there are certain situations in which the virus can act like an airborne disease which includes certain clinical settings where people are receiving intensive medical treatment. In typical situations, the coronavirus is spread through respiratory droplets after a person coughs or sneezes, but these droplets are generally larger than what is considered airborne.

  • Influenza

The seasonal “flu” virus spreads easily from person to person through the air. There are many strains of the flu which continuously adapt to the human immune system.

  • The common cold

The condition also known as “a cold” is usually caused by rhinovirus. There are many strains of rhinoviruses, and the strains adapts to make it easier to infect humans.

  • Varicella zoster

This virus causes chickenpox and spreads easily among young children. The virus will result in rashes on the body and is typically widespread on the body and is made up of small red spots that turns into itchy blisters which scabs over in time. Chickenpox typically spreads for 48 hours before a rash shows, which is the reason behind its contagiousness. This virus is usually spread through the air or by touching the rash.

  • Mumps

This virus usually affects the glands just below the ears which causes swelling and in some cases, a loss of hearing. Vaccination is considered important to prevent the disease.

  • Measles

This illness is caused through contact with a person who has the virus, or by inhaling particles from their sneezes or coughs. Vaccination is also essential for the prevention of this disease.

  • Whooping cough (pertussis)

This is a contagious, bacterial illness that causes the airways of one to swell. The hacking cough as a result of this illness is persistent and is generally treated with antibiotics early on to prevent damage. These are some of the common airborne diseases and does not cover the entire spectrum of airborne diseases. The length of an illness caused by a common airborne disease can vary from a few days to week, but it is usually dealt with easily.

Is flying still safe in the coronavirus era?

Studies done on virus transmission in planes

The air quality on a commercial airliner is quite high, as the air volume inside the cabin is completely refreshed every 2-4 minutes. Air flows into the cabin vertically – air enters from overhead vents and is send downward in a circular motion, exiting at floor level. Once cabin air exits, about half is dumped outside, and the rest is send through high-efficiency particulate air (HEPA) filters, similar to those used In hospitals, before being mixed with fresh outside air and entering the cabin again.

However, passengers and crewmembers moving up and down the aisles can disrupt this airflow, altering the path of any airborne particles. And while the HEPA filters used in commercial aviation can filter out 99.97% of virus sized particles, it cannot capture every respiratory droplet or viral aerosol before someone else inhales it.

Still , the design of air-handling systems on commercial aircraft like the Airbus A350 makes it unlikely one will be breathing in air from anyone more than a few rows away. In fact, a 2018 study that examined the transmission of droplet-based mediated respiratory illness during long-haul flights found that an infectious individual with influenza or another droplet-transmitted respiratory infection was highly unlikely to infect passengers seated farther away than 2 seats on either side or one row in front or in back.



Measures taken by airlines to ensure that their plane is clean

As the coronavirus outbreak continue to grow around the world, airlines are doing their part to help travellers stay safe from this virus, from offering flexible change policies to taking precautions to clean their aircraft entirely therefore making it safe for use.


Aircraft cabins are usually cleaned to varying degrees during the turnaround time for each flight. This usually entails picking up trash, switching out linens and wiping down surfaces with disinfectant.


  • Aircraft fogging Some airlines have started spraying a high-grade disinfectant on every surface in the cabin after every single flight. The disinfectant is sprayed through a fog machine that aerosolizes it so that it can coat the air and all surfaces in the cabin which includes the ceiling, seats, trays, floors, lavatories, crew rest areas and also the galleys. Delta airlines has been doing this on flights arriving to its hub from Asia since February and has expanded the practice to all trans-pacific arrivals and flights from Italy to New York JFK and Atlanta.

  • Sanitising of aircraft US airlines have said that they are focusing on sanitising the hard surfaces that passengers commonly touch in the cabin which includes the tray tables, seat-back screens, and pockets and also the seat belts that is getting a wipe down with hospital grade, EPA- approved disinfectant. Airlines also has started to provide passengers with personal care packs, which includes mask and sanitising wipes.

  • High-grade air filters All US carriers say the majority of their aircraft is equipped with high-efficiency particulate air filters or also known as HEPA filters. These were always in use, but in the midst of the pandemic, airlines are paying even closer attention to their air filtering system. The devices remove 99.7 percent of airborne particles and provide a complete change of air in the cabin every 2-4 minutes. These are the same air filtration systems used in hospital operating rooms. Many of the systems also draws in exterior air to refresh the cabin.

  • Cabin crew precautions Most flight attendants are now instructed to wear personal protective equipment such as medical-grade gloves, masks and even face shields for some airlines. Flight services such as meal service, hot towel service has been readjusted in order to minimise contact between passengers and cabin crew. United airlines for example have all its cutlery, tableware, dishes and glassware sanitised before they are washed.

During this COVID-19 era, passengers do not feel as safe anymore to fly and travel. Nevertheless, airlines are continuing to do their best to keep the flying environment as safe as possible for everyone.



Watch a video to learn more



17 views0 comments

Comments


bottom of page