As cases of coronavirus infection proliferate around the world and governments take extraordinary measures to limit the spread, there is still a lot of confusion about what exactly the virus does to people’s bodies. The symptoms — fever, cough, shortness of breath — can signal any number of illnesses, from flu to strep to the common cold.
The virus is spread through droplets transmitted into the air from coughing or sneezing, which people nearby can take in through their nose, mouth or eyes. The viral particles in these droplets travel quickly to the back of your nasal passages and to the mucous membranes in the back of your throat, attaching to a particular receptor in cells, beginning there. Coronavirus particles have spiked proteins sticking out from their surfaces, and these spikes hook onto cell membranes, allowing the virus’s genetic material to enter the human cell. That genetic material proceeds to “hijack the metabolism of the cell and say, in effect, ‘Don’t do your usual job. Your job now is to help me multiply and make the virus,’” said Dr. William Schaffner.
As copies of the virus multiply, they burst out and infect neighboring cells. The virus then “crawls progressively down the bronchial tubes,” Dr. Schaffner said. When the virus reaches the lungs, their mucous membranes become inflamed. That can damage the alveoli or lung sacs and they have to work harder to carry out their function of supplying oxygen to the blood that circulates throughout our body and removing carbon dioxide from the blood so that it can be exhaled. The swelling and the impaired flow of oxygen can cause those areas in the lungs to fill with fluid, pus and dead cells. Pneumonia, an infection in the lung, can occur.
(Source: https://www.nytimes.com/)
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