Some viruses, like other germs, can live on surfaces. You become infected when you touch them and then touch your eyes, nose or mouth. But many viruses spread through the air. These are called airborne viruses. A range of illnesses — from mild colds to the flu to COVID-19 — are caused by airborne viruses.
A sea of aerosols
Every time you talk, sneeze or cough, you breathe out more than just air. You also exhale lots of tiny fluid particles. These come in a wide range of sizes. The smallest particles, called aerosols, can hang in the air for minutes or even hours, and they are able to travel more than six feet through the air.
Just as you breathe out aerosols, you can also breathe in aerosols that others exhale. And some viruses can hitch a ride in them. The more viruses that are in the air, the more likely you are to breathe them in and become infected.
Spreading indoors and out
How much virus is floating around in the air depends on where you are. Indoor spaces tend to be poorly ventilated compared to the outdoors. When aerosols collect in the air, you’re more likely to breathe them in and get infected. Good airflow can quickly clear indoor air of aerosols. This lowers the chance that people will breathe in enough viruses to become infected. Outdoors, aerosols can float off or blow away.
Preventing infection
The best defense against airborne viruses like the flu, is getting Centers for Disease Control and Prevention (CDC)-recommended vaccines to help your body ward off germs. Maintaining a healthy lifestyle can also help keep you from getting ill. That includes a healthy diet and regular physical activity.
Fuente: National Institutes of Health (NIH)
