Stand 4 meters from a person sneezing and wait 45 minutes to escape the bacteria

Cover your mouth and wash your hands, advice never admit.

When a person sneezes, they will spread into a cloud environment called 'aerosols'. This cloud carries all sorts of horrible things, from body fluids, gas molecules to pathogens like viruses and bacteria.

Have you ever wondered: How far is the influence of these clouds?If the sneeze position is less than 4 meters, the researchers will have to lie in this less secure cloud for 45 minutes. It is a fairly long period of time, increasing the risk of infection of diseases.

If the sneeze position is below 4 meters, you will have to lie in this less secure area for 45 minutes.

Stand how a person sneezes 4 meters and waits for 45 minutes, you can escape the dangerous bacteria
The answer is given by scientists from Queensland University of Technology, Australia. Their research aims to 'understand the droplets [aerosols] that carry bacteria released from sneezing. or how long the cough will travel, and how long it will last to infect others , "said Lidia Morawska, one of the authors.

She and her team focused on a bacterium called Pseudomonas aeruginosa . Four months ago, it was just ranked at the top of the table by the World Health Organization (WHO), the world's 12 most dangerous viruses.

P. aeruginosa is a common antibiotic-resistant pathogen that causes infections such as pneumonia, respiratory infections and blood infections. The most vulnerable subjects are those who have existing diseases, especially cystic fibrosis - a disease that affects the lungs and digestive system for a lifetime, leading to increased sweating and mucus.

Until now, we have understood quite well about P. aeruginosa. However, the spread of this bacterium from coughs and sneezes is still not clear.

Most studies on this issue are based on simulations only. In it, scientists use artificial devices such as sprayers to create a fake 'explosion' from sneezing. They observed the spread of air droplets, then surmised the same thing happened with bacteria in practice.

Morawska is not happy about this. She said that sneezing of sprayers and humans is completely different, so a more realistic research method is needed. She and her team designed a model of sneezing research in real patients, and successfully ensured its safety factors.

There should be a better method of studying sneezes.

'We have developed a new technique to study the short-term and long-term decay of aerosols released from humans. The technique does not cause ambient air pollution when it is done, ' Morawska said.

In case you have not heard about the concept of aerosol, it is like a glue cloud with droplets of liquid and solid, dispersed into a gas environment. Mist, dust pollution is aerosols in nature. Sneezes and coughs are aerosols created by humans. Paint sprayers, nasal sprays, deodorant sprays . are all aerosol tools.

Aerosol disperses and then dissolves into the environment. It is an interesting phenomenon in many cases. But with sneezes and coughs, aerosols are a condition for spreading germs.

The technique invented by the Morawska group is called TARDIS for short. It allows scientists to observe how matter droplets, such as bacteria, will spread, stick to the surrounding surface and survive over time after more shots.

With the ability of TARSIS to work, Morawska used it to study the coughs and sneezes of two patients with cystic fibrosis and chronic pseudomonas aeruginosa infection. What she discovered:

'As soon as the small droplets from the explosion blew into the air, they quickly dried, cooled and became light enough to fly in the air. They are also partially weakened when exposed to oxygen in the environment. Larger droplets take longer to evaporate , 'Morawska said.

Most drops in the cloud will be so dry that bacteria cannot exist inside them. This process usually takes place very quickly. Every 10 seconds, half of the bacteria in these droplets will die.

However, there is still a small set of droplets that bacteria live in which have a longer half-life. It takes every 10 minutes, the amount of bacteria in it is reduced by half. It explains why bacteria will survive up to 45 minutes within 4 meters of sneezing.

'This indicates some bacteria such as P. aeruginosa are resistant to rapid decomposition caused by natural biological processes. And so they survive in the air long enough to create infectious risks, 'Morawska said.

You can't stop sneezing, but if you miss it, cover your mouth.

The ultimate cause of this persistent resistance to P. aeruginosa has not been clearly defined. But scientists have come up with several theories:

'We think this happens, because the droplets are born in different places in the respiratory tract, so they carry different "bacteria" , "Morawka suggested. 'Large droplets containing bacteria take longer to evaporate, making bacteria more resistant, maintaining their persistence in the air'.

All explanations will need to continue to be tested by experiment. But in fact bacteria survive for 45 minutes and within a radius of 4 meters from sneezing has been confirmed. what does it mean? It will provide important insights, helping doctors to control infections in the hospital environment.

But in real life, research continues to reinforce a minimum polite principle: You can't stop sneezing, but if you miss, cover your mouth and wash your hands so you don't affect others.