Why Covid will get worse in winter esp in indoor settings
From a friend who is air scientist in USA
With the onset of winter, relative humidity levels indoors dip, the particles that people emit through talking or coughing get smaller and smaller. These particles are made up of mucus, salts, protein, and cell parts—but mostly water. The drier the air around them, the faster that water evaporates. And the smaller the particles get, the longer they can stay in the air, the farther they can travel, and the deeper into the lungs they can be inhaled. Any viruses lurking inside these particles go along for the ride.
If they land inside a susceptible person’s respiratory tract, that can spell trouble. Of course, the body is equipped with multiple layers of security to protect against would-be invaders. The first line of defense is a physical barrier maintained by the cells that line the nasal passages. Some of these cells secrete mucus—two layers of the slippery, stringy, substance, with two different viscosities. Other cells inside the nose and throat have tiny, anemone-like projections called cilia, which beat in synchrony in the more watery layer. That motion moves the thicker, top layer of mucus like a conveyor belt away from the lungs. This mucosal current catches any viruses or bacteria (or other irritants like pollen and ash) that land on it and sweeps them away to be swallowed or coughed out. But if the air is too dry, these mucus layers dessicate, squishing the cilia and immobilizing them. more
With the onset of winter, relative humidity levels indoors dip, the particles that people emit through talking or coughing get smaller and smaller. These particles are made up of mucus, salts, protein, and cell parts—but mostly water. The drier the air around them, the faster that water evaporates. And the smaller the particles get, the longer they can stay in the air, the farther they can travel, and the deeper into the lungs they can be inhaled. Any viruses lurking inside these particles go along for the ride.
If they land inside a susceptible person’s respiratory tract, that can spell trouble. Of course, the body is equipped with multiple layers of security to protect against would-be invaders. The first line of defense is a physical barrier maintained by the cells that line the nasal passages. Some of these cells secrete mucus—two layers of the slippery, stringy, substance, with two different viscosities. Other cells inside the nose and throat have tiny, anemone-like projections called cilia, which beat in synchrony in the more watery layer. That motion moves the thicker, top layer of mucus like a conveyor belt away from the lungs. This mucosal current catches any viruses or bacteria (or other irritants like pollen and ash) that land on it and sweeps them away to be swallowed or coughed out. But if the air is too dry, these mucus layers dessicate, squishing the cilia and immobilizing them. more
Viewed by 284
That means winter is a health hazard as compared to summer and monsoon seasons in India. But in reality it is other way around. more
Nov 18
