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Yet more about COVID – 19

Coronavirus is the type of virus that causes common colds, but it can also cause more serious diseases such as SARS, MERS, or COVID – 19. The virus is only about 0.025 µm in diameter, far smaller than the human eye can see even with the best optical microscope. In comparison, a fine human hair is about 40 µm in diameter. When people talk, cough, or sneeze they eject small droplets which vary greatly in size but the average is about 1 µm. Each small droplets can hold hundreds of thousands of viruses and the droplets can persist in the air for several hours.

This image is that of a coronavirus as taken by an electron microscope. The virus gets its name from the small structures on the surface which look like crowns. When the virus encounters a human cell, the crown attaches to the cell’s surface and injects its own RNA into the cell, which then takes over the cell mechanisms and produces copies of the virus. They eventually cause the cell to burst which can release up to 50,000 new viruses.

COVID-19 Virus is a new virus in humans that entered the population for the first time in 2019. The virus cannot live long outside a human host, and the main vector for its transmission is those who travel to and from infected areas. We have little natural immunity to the virus and about 97% of those infected recover within 14 days. Particularly severe cases must be put on a ventilator to keep the patient breathing until the virus runs its course. The virus is sometimes lethal for the elderly and those with compromised immune systems.

Symptoms: The symptoms of the virus are headaches, fever, pink itchy eyes, coughs, sneezes, sore throat, tightness in the chest, difficulty breathing, inflamed toes, and loss of smell or taste. The incubation period after exposure is from 5 to 14 days. People exposed may transmit the virus to others before they experience symptoms. However, some people with the virus may never have symptoms, yet still be able to transmit the virus to others.

Transmission: The virus is transmitted by direct contact between individuals from small droplets ejected when an infected person talks, coughs, or sneezes. The social distance of 6 feet is usually enough to prevent the virus being transmitted directly. However, small droplets from coughs or sneezes may travel much further than 6 feet and may contain hundreds of thousands of viruses. The droplets may persist in the air for several hours. They eventually settle on surfaces where the virus may live for up to several days, depending on the type of surface. For example, the virus is found to exist for a day on cardboard and up to three days on tile or plastic.

Infection: The virus infects a person by entering through their eyes, nose, or mouth. It may happen from being near an infected person, particularly if they are coughing or sneezing. Small droplets that settle on surfaces are transferred when you touch the surface and then they may infect you when you touch your face. Once on your hands, you will transfer the virus to everything else you touch until you wash your hands or kill the virus with hand sanitizer.

Precautions: The best precautions aim to keep the virus from being transmitted from person to person. From what we know about the virus, the following guidelines have been developed to keep it from spreading:

• Avoid close contact with people who are sick. Stay home as much as possible, particularly if you may be sick.
• Keep a social distance of at least 6 feet from other people when you are in public.
• Avoid touching surfaces in public places. Assume anything you touch may be contaminated.
• Wash your hands often for at least 20 seconds with soap and water or use sanitizer.
• Avoid touching your face, particularly rubbing your eyes.
• Wear a mask when in public, primarily to keep you from infecting other people. Remember you may spread the virus even though you have no symptoms.
• Avoid traveling to and from areas that have high levels of infection. Human movement is the main vector for the spread of the virus.
• Avoid gatherings, particularly those which have more than 10 people.

Get vaccinated. Vaccines are now available which are free and effective. Two doses plus a booster will prevent most infections or, in case of an infection, will make the symptoms much milder. Avoiding hospitalization is very important, especially now as many hospital emergency rooms and ICUs are overloaded with Covid – Omicron cases. It is much less likely that a fully vaccinated person will get the Omicron virus. Even if they do, it is usually a much milder case that does not require hospitalization. Over 90% of the patients in ICU or on ventilators with Covid have not been vaccinated. The Omicron virus tends to infect the upper respiratory system rather than the lungs, so it tends to be milder, but like any infection- it can move to the lungs.

Omicron and Masks: You may have heard that masks are less effective against the omicron strain of the coronavirus. That is NOT correct. An N95 mask blocks 95% of small droplets that are 0.05 µm in size, no matter what the droplet contains. Recent studies have shown that the omicron variant is more effective at entering cells. Because of this, it takes fewer droplets to cause an infection.
Masks are still the most effective way to prevent the transmission of the virus from one person to another. If both people are wearing masks, there is a 99.8% chance that the virus will be blocked from being transmitted. If both people are wearing standard green surgical masks, the probability drops to 99% – but that is still pretty good.

The Future: Most states have issued orders based on the precautions above in order to keep their citizens safe. However, if the orders remain in place too long they will hurt the economy, but if they are relaxed too soon we may experience a second round of the virus. This would prolong the pandemic and hurt businesses even more. Most states, sometimes under political pressure, are relaxing the guidelines stepwise in order to allow businesses to open while keeping an eye on the rate of infection.

No matter what your state orders, it would be a good idea to follow the precautions above until the OK is given by healthcare professionals. It is imperative that you become vaccinated to protect yourself and your loved ones. The decision up is up to you. Please follow the guidelines to keep yourself and others safe.

Note: This article was updated on 01/10/2022.

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