How is the virus spread if you share a plane with an ill person?

Are you afraid of flying to increase your chances of getting an infection? Imagine you have to get into a closed box with more than 100 people, but unfortunately there is only one person with the flu virus, you risk going home with two rows of runny nose.

But is everything as dangerous as you think?

It turns out, it depends on your seat position. A new study published in the Proceedings of the National Academy of Sciences shows that the highest rate of influenza virus infection on airplanes is within a radius of 1 meter.

This means that if a passenger has the flu, he will have an 80% chance of infecting people who sit in 2 rows of seats next to him and 2 front seats. This suggests that the passengers in the center of the aircraft will have more opportunities to bring the disease home than the passengers sitting in the front and back rows, although their risk is quite small.

The highest prevalence of influenza virus infection on aircraft is within 1 meter radius.

Every year, about 3 billion of us have to travel by plane. Combined with the popular perception that infectious diseases are easily spread by air, it is surprising to know that very few studies focused on answering this question in detail.

Tracking the pathogen that spreads on the plane seems like nothing. We have a variety of tools for synchronous data collection such as cameras, RFID tags, ultrasound, infrared . These technologies are being used to track passengers' activities on reasonable flights. due to security.

With their skills, scientists can also use them to monitor the spread of pathogens. But Howard Howard Weiss, a mathematician from the Georgia Institute of Technology and co-author of the new study, said:

" There are not any quantitative studies of activities, behaviors or social interaction among passengers during the flight. We have not seen any studies examining the virus transmitted by air. steaming in the air and cabin surfaces ".

To answer the question: " How can infectious diseases spread on airplanes? ", Weiss and co-author Vicki Stover Hertzberg from Emory University, designed and tested an observation technique. New record all the movements of passengers and crew in the cabin.

They tracked 10 flights with this new technology, 8 of which were flights during the flu season. In addition to recording the entire movements of crew and passengers, the team also collected samples of air in the cabin and on surfaces such as seats, windows, luggage compartments . to find flu viruses.

The planes are small and carry 144 passengers and there is only one path in the middle.

Simulate the risk of infection on a plane from a passenger in the middle row

" This is the first study to quantify the mobility, behavior and social communication of air travelers to estimate the likelihood of transmission by data models, " Weiss said. " Simulations provide convincing evidence that if you do not sit in a radius of 1 meter compared to passengers infected with influenza and wash your hands often, you will not get infected during that flight."

Weiss and the authors have an example of an infected person sitting in the middle of an airplane. According to their computer simulation, passengers sit right in front of or behind the person, and the left and right seats are at risk of infection of more than 80%.

But for others, that number has dropped to only 3%. So if a person carries the flu virus on the plane, they are only at an average risk of infection for about 4-6 other passengers.

Interestingly, of the 229 samples collected from the environment inside the cabin, none of the samples contained traces of 18 common respiratory tract viruses. It seems contrary to many people's worries, the plane is not a disease.

Research is also interesting in that it reveals the behavior of passengers corresponding to their seats. This is very important because the more people travel, the more opportunities they will have to be exposed to the pathogen . Or if they are infected, there are more opportunities to spread them to other passengers.

Weiss and colleagues' simulations show: About 40% of passengers never leave their seats during flights, 40% of other passengers stand up once, and 20% get up and move twice up. For every 10 passengers sitting by the window, 4 people will stand up. The number is 6 people in the middle row and 8 people sit near the aisle. Passengers who leave the seat will return in an average of 5 minutes.

Combining all this data, the scientists concluded that the possibility of virus infection on aircraft is low , at least on small planes with only one path and short route (2-5 flight hours). But if that's true, why are we still often sick after going on business or traveling?

" People may have been infected while they stayed in the airport lobby, while boarding the plane [more than when they were in the cabin], " the team said. " In addition, some passengers may have been infected by other sources before or after the flight . "

People should not be too worried about the information from the new study from which to fear flying.

Edsel Maurice Salvaña, a molecular biologist at the National Institutes of Health at the University of Manila Manila, said the new study is important because we need to better understand the path of disease transmission on flights. The team did a great job mapping the patient's movements and conducting an additional environmental test for a group of 18 types of respiratory viruses.

However, the weakness of this study is that it has not simulated viruses and infectious bacteria with a more contagious range such as chickenpox, measles and tuberculosis.

However, experts believe that people should not be too worried about the information from the new study from which to fear flying. In fact, it has shown a low risk of transmission. Only people with new immune deficiencies need to worry about flying during the flu season.

In addition, this study encourages people who are sick (both passengers and crew) to rest and restrict their flights. In addition to wearing masks, people should also wash their hands to prevent illness. This is one of the most effective ways to protect you, if unfortunately you have to fly with a passenger next to sneezing.

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