Coronavirus is a diverse family of viruses that can infect a large number of hosts. Due to their nail-like protrusions on the surface, they may resemble a crown. In Latin, corona means crown – hence their name.
There are human coronaviruses that cause mild respiratory problems, such as colds.
Researchers from Penn State University College of Medicine, USA, stated that the human coronavirus “has long been considered an insignificant pathogen”.
But three have emerged in the 21st century that have caused alarming illness and death:
- SARS-CoV (severe acute respiratory syndrome coronavirus)
- MERS-CoV (Middle Eastern Coronavirus Respiratory Syndrome)
- SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2)
What do they have in common?
All coronaviruses “are large, enveloped, positive-strand RNA viruses” that can be divided into four groups:
“Alpha and beta coronaviruses are known to infect humans,” say the researchers.
The surface nail protein (S) glycoprotein is “critical” for binding to host cell receptors.
“Cases of severe atypical pneumonia were described in Guangdong Province, China” in 2002.
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Public health measures put an end to the SARS-CoV pandemic of 774 people who lost their lives.
In 2012, MERS-CoV emerged. Characterized by “sporadic zoonotic transmission and limited chains of human spread”.
According to the World Health Organization (WHO), as of November 2019, MERS-CoV has caused 858 deaths, mostly in Saudi Arabia.
Those with MERS-CoV have “gastrointestinal symptoms” explained by MERS-CoV (S) glycoprotein binding to dipeptidyl peptidase 4 (DPP4) – also present in the lower respiratory tract, as well as in the gastrointestinal tract.
These two remarkable viruses illustrated zoonotic coronavirus posed a “threat” to humans.
In response, the WHO began research into the development of countermeasures against coronavirus in 2017.
As with SARS-CoV, this virus that stormed the world by storm 2020 also uses ACE2 as a receptor to bind with.
In addition, SARS-CoV-2 is also derived from bats, says Healthline.
What distinguishes SARS-CoV-2 from other coronaviruses is the impact it has had on the world.
Because “80 percent of people” infected with SARS-CoV-2 have a mild illness, it is highly transmissible when people continue with their daily lives.
SARS-CoV, on the other hand, led to more “severe” cases and is considered more deadly in infection.
As vaccine trials are under way to deal with coronavirus and public health measures are in place, this pandemic may soon end.