Do you remember the fear of the COVID pandemic in early 2020? When handwashing stations and hand sanitizers were everywhere, and people were afraid to even touch doorknobs? We all thought that this disease could only be spread by someone coughing, sneezing, or touching a surface that had the virus on it. But, a small incident changed all of our initial beliefs. That's what we're talking about today.
The event that changed everything
This happened in March 2020, in Washington, USA. 61 members of a choir called the 'Skagit Valley Chorale' joined for a two-and-a-half-hour practice. They followed all the health guidelines at the time. No one touched anyone else, kept a distance of about two meters, and used hand sanitizer thoroughly.
But surprisingly, within a few weeks, 52 of these 61 people had contracted COVID-19! Several had to be hospitalized, and unfortunately, two died.
Scientists were surprised at first. Everyone wondered, "How did this happen?" They were far apart, they didn't touch each other, so how did so many people get sick at once?
That's when a scientist said, "There was only one thing that everyone in that room shared. That was the air ," and "There's no doubt that the disease spread through that air."
This incident was a crucial event that changed many of the things we thought about the Covid pandemic.
So, have we been thinking wrong for so long? The old 'droplet' view
In fact, for the past hundred years or so, health experts have believed that respiratory illnesses like colds and influenza are spread primarily through large, heavy droplets. Simply put, the droplets of saliva that are released when someone coughs or sneezes.
According to this view, the disease develops if:
- You should stay very close when a sick person coughs or sneezes.
- Or, you can get sick if you touch a surface (like a table or doorknob) that has large droplets on it and then touch your nose, mouth, or eyes with that same hand.
This old belief (Droplet Dogma) is why we were advised to maintain a 6-foot distance and wipe down everything with disinfectant during the early days of Covid.
But with what happened to that choir, scientists realized that there was a big flaw in this story somewhere. There must be a more subtle way for the disease to spread.
'Droplet' and 'aerosol' - what's the difference?
This is where we come across a new word - 'aerosol'. This is very important to understand. Think of a spray bottle. When you spray it, large drops of water fall to the ground, and there are also small, invisible water particles floating in the air, like a mist, right? That's how it is.
'Droplets' are like those big drops. 'Aerosols' are like those tiny particles floating in the air.
Let's look at the difference between the two this way.
| Attribute | Large droplets (Droplets) | Very small particles (Aerosols) |
|---|---|---|
| Size | Relatively large (although not visible to the eye) | Very small (like smoke) |
| Effect on gravity | It falls to the ground quickly (in a few seconds/minutes) due to its weight. | Because it is so light, it can float in the air for minutes, maybe hours. |
| Travel distance | A short distance (about 1-2 meters). | It can even spread throughout a room. |
| How it spreads | By directly entering the body when someone coughs or sneezes nearby. | When someone with the virus breathes, talks, or sings, it gets into the air and is inhaled. |
When the members of that choir sang, the air in the entire room would have been filled with these tiny particles (aerosols) from their breath. Even though they were far apart, they all breathed the same air, so everyone got sick. This is called airborne transmission .
How new knowledge has changed our lives
With this discovery, the methods we used to control the epidemic completely changed.
From wiping surfaces to thinking about the air
At first, we thought that wiping down floors, tables, and doorknobs was the most important thing. But after realizing that it's airborne, we learned that there's something even more important. And that's good ventilation.
Simply put, keeping doors and windows open and using a fan to circulate the air reduces the concentration of virus particles in one place.
The true value of the mask
Initially, masks were worn to stop the large droplets that we coughed out. But later it was realized that a good mask like the N95 can filter out even these small virus particles (aerosols) floating in the air. Therefore, the importance of the mask increased even more.
This knowledge will help us a lot to protect ourselves not only from Covid, but also from any future respiratory disease pandemic.
Take-Home Message
- Respiratory diseases like COVID-19 can be spread through large droplets that are released when someone coughs, as well as through very small particles (aerosols) that float in the air when they speak or breathe.
- The risk of spreading the virus is higher in closed spaces (rooms, buses). Therefore, it is very important to maintain good ventilation , which means keeping the windows open.
- Wearing masks helps protect against both large droplets and small particles floating in the air.
- Science is not static. Our knowledge and understanding change as new evidence becomes available. Pandemics are a prime example of that.
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