What are Common Human Coronaviruses?

The currently spreading Coronavirus disease, COVID-19 has turned out as horrifying and almost all countries in the world are already in the grip of the corona fever. The coronavirus that causes COVID-19 is called novel coronavirus by medical experts. This name was given just because it is the latest version of coronavirus that has been there for a very long time. According to the Journal of Virology published in the year 2013, coronavirus have been existing for millions of years. The number of Corona cases are increasing at alarming rate in US, entire Europe and in other parts of the world. In mid-1960s the Human Corona Viruses were first identified. There are seven Common Human Coronaviruses and they are 229E, NL63, OC43, HKU1, MERS – CoV, SARS – CoV and SARS – CoV – 2. The last one in the above list – SARS – CoV – 2 is the Novel Coronavirus which causes the latest Coronavirus disease COVID – 19.

Evolution of new human coronavirus

The four Human Coronaviruses that commonly affected humans were 229E, NL63, OC43 and HKU1. The coronaviruses that affect animals sometimes become capable of affecting humans also and such viruses evolve as new human coronavirus. The latest example of this type of Human Coronavirus is SARS – CoV – 2 which causes COVID – 19. SARS – CoV and MERS – CoV are other two examples for above type of Human Coronavirus. All types of Common Human Coronaviruses can cause upper respiratory symptoms in humans and as a result people who are infected with the virus will develop sneezing and coughing. These coronaviruses will also cause fever. According to Dr. John Swartzberg of Berkeley School of Public Health, University of California, most of the common human coronaviruses are relatively harmless and all of them except three types cause common cold.

The four Common Human Coronaviruses – 229E, NL63, OC43 and HKU1 are spread all over the world and children and adults the world over get infected. The remaining three Common Human Coronaviruses – MERS – CoV, SARS – CoV and the latest one SARS – CoV – 2 that causes COVID – 19 are very harmful and dangerous. The SARS – CoV caused Severe Acute Respiratory Syndrome (SARS) during the period 2002 – 2004 and Middle East Respiratory Syndrome (MERS) was caused by the MERS – CoV virus in the year 2012. All these three viruses come under Betacoronavirus, which is one among the four subgroups of coronavirus. It is believed that all the three originated from a single animal population.

Why SARS – CoV – 2 is so dangerous?

When a coronavirus transmits from animal to human, that will be the end of that virus in most of the cases. However, very rarely, the virus gets multiplied and also transfers. When this rare thing occurs the outcome will be a virus that can cause a very dangerous disease that can kill people who are affected. This is mainly because the human body is without immunity to that particular virus. The SARS – CoV – 2 virus that causes COVID – 19 might be one such virus. Medical fraternity is not sure whether human body will become immune to this virus as a result of exposure to the virus. The MERS CoV virus that caused MERS went on circulating whereas the SARS – CoV virus that cause SARS disappeared effectively. Health care experts are unable to predict what will happen to the SARS – CoV – 2 virus which has caused COVID – 19. Researchers have to go a long way to develop a vaccine for COVID – 19.