Briefly Explained: Coronavirus and Severe Acute Respiratory Syndrome 

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Coronaviruses are a big family of viruses that are associated with causing illness ranging from the common cold to something more severe. The more severe illness caused by coronavirus includes Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS). 

MERS is a viral respiratory disease that was discovered not so long ago among humans. First discovered in Saudi Arabia, it managed to spread to some other countries including the United States. It caused severe respiratory illness such as cough, fever, shortness of breath. Many patients couldn’t recover and died. 

Severe Acute Respiratory Syndrome (SARS)

In terms of severity, Severe Acute Respiratory Syndrome is even more dangerous. It is a highly contagious disease that spreads like nothing else. SARS is a disease with a zoonotic origin, which is caused by SARS-CoV or SARS-CoV-1 coronaviruses. 

The first detected coronavirus strain is SARS-CoV, which caused the first SARS outbreak between 2002-2004. It was relatively less malignant, with 8,422 cases and an 11% death rate. No new cases have been reported since 2004 and the virus is now considered eradicated. It does have the possibility to re-emerge again. 

The second coronavirus strain detected is the Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2). It spread all over the world and brought the world to a standstill with the Covid-19 pandemic. 

How Long Coronaviruses Existed?

While Severe Acute Respiratory Syndrome is a recent illness among humans, coronaviruses have been on earth for ages. The most recent common ancestor or MRCA can be traced back to 8000 BCE. 

There are also some models that trace the common ancestors back to more than 50 million years. They base their arguments on the basis that the coronaviruses existed and went through long term coevolution with avian species and bats. Fortunately, they didn’t cause SARS back then.