First human Coronavirus was discovered in 1965 by Tyrrell and Bynoe. It was demonstrated that when this virus was introduced into the noses of human volunteers, colds were produced. Later in 1960s, these viruses were named Coronavirus – corona denoting the crown-like appearance of the surface projections. Since the discovery of Coronaviruses, they remained inconsequential until one of the strains SARS-CoV caused SARS outbreak in 2003. This is followed by MERS outbreak in 2012 caused by MERS-CoV and COVID-19 pandemic since December 2019 caused by Novel Coronavirus – 2019-nCoV or SARS-CoV-2.
According to a study published in Lancet, Rhinoviruses account for 30-50% of common cold infections. Followed by Rhinoviruses, Coronaviruses are the cause in 10-15% of the cases. Influenza viruses accounted for 5-15%, and Respiratory Syncitial Virus (RSV) in about 5% of the cases. Since their discovery in 1965, Coronaviruses are known to cause only common cold. Several strains were identified and all of them cause only common cold. Rarely, they were identified as a cause for more severe illness like pneumonia or Acute Respiratory Distress Syndrome (ARDS). Until Coronavirus caused SARS outbreak, they were never considered as lethal. With the third outbreak, now, we all know how deadly Coronaviruses can be.
In summary, Coronaviruses are identified as the second most common cause of the common cold syndrome. Every one of us may have been infected by Coronavirus sometime in our lives.
References:
doi: 10.1097/01.inf.0000188166.17324.60