Last updated on March 30, 2021
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Science made tremendous progress in understanding COVID-19 from the moment China reported the outbreak to the World Health Organization (WHO) on December 31, 2019, until one year after the WHO officially declared a pandemic on March 11, 2020. However, by March 2021, many questions remained unanswered.
Studying something as small as the viral particle that causes COVID-19 presented enormous challenges. Fortunately, by 2019, scientists already had extensive knowledge of coronavirus—their structure, replication process, and general characteristics. However, how this particular novel coronavirus would behave depended on its unique genetic material. Deciphering its genome was relatively straightforward, and Chinese scientists successfully sequenced it by January 10, 2020. Yet, understanding how these genetic differences would influence the virus’s behavior required much more time and research.
From the start, we knew the basics of how to protect ourselves and others. Scientific knowledge of the virus advanced rapidly, but it took months to fully grasp how it attacked the human body. This understanding was crucial in helping to reduce the mortality rate of hospitalized patients.
When reports of a “mysterious pneumonia” emerged in Wuhan, China, it was clear that the virus primarily targeted the lungs, much like SARS. This alone made it a serious concern. However, as the virus spread worldwide, it became evident that it also affected other organs. It traveled through the bloodstream, damaging blood vessels and triggering a wide range of complications. Scientists observed that it caused blood clots and disrupted the immune system in severe and unpredictable ways.
Although no universal cure was discovered, several drugs proved effective in treating hospitalized patients, depending on the progression of the disease. Then, exactly one year after the initial outbreak alert, the WHO approved the first COVID-19 vaccine on December 31, 2020. By March 30, 2021, approximately thirteen different vaccines had been approved in various countries, offering hope for a return to pre-pandemic normalcy.
Continue with What we knew about the origin of Covid-19.
Continue with What we knew about the structure of the SARS-CoV-2 virion.
Continue with What we knew about Covid-19 spreading in a population.
Continue with What we knew about how the disease spreads in the human body.
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©2020, 2021 Dr. Michael Herrera