Origin Of COVID-19 :- All That You Want To Know

   We are amidst a world wide catastrophe that is swallowing the human population now. When I am writing this (Indian Standard Time-6:00 a.m.,26th March-2020), there had been 468,577 coronavirus cases reported, 21,185 deaths and 113,817 recovered reports. Among them, Italy’s condition is more pathetic. Because the death tolls are more in number than the death tolls in the suspected country of origin, China. And then stands the USA. So you guys can guess what is the reason behind the declaration that coronavirus is a pandemic, by W.H.O (World Health Organisation)
  

In order to understand the treatment method of the so-called COVID-19, it is essential to understand the origin of the disease. According to the definition given by W.H.O, “Coronavirus Disease” (COVID-19) is an infectious disease caused buy a newly discovered coronavirus. Those who are affected with this disease experience mild respiratory problems. The only consoling information regarding this is, it can be recovered without requiring any kind of special treatment.
  

Now we can try to identify how it’s origin occurred. Scientists are undertaking tremendous efforts to comprehend the origin of COVID-19 and the virus that causes it: SARS-CoV-2. Hitherto, they believe that this particular virus may have developed in bats and pangolins. However, in accordance with the genomic comparisons, there is another possibility. The SARS-CoV-2 virus is maybe the result of a recombination between two different viruses. It simply means, the exact origin of the virus is unknown.
  

27 persons of the first 41 people hospitalised (i.e. 66% of the 41 people) in December, passed through a market in the Wuhan city. But, according to a study conducted at Wuhan hospital, the very first human case identified have no frequent travel history with this market. Instead, a molecular dating estimate based on the SARS-CoV-2 genomic sequences indicates an origin in November. (To know more about this, visit : https://onlinelibrary.wiley.com/doi/full/10.1002/jmv.25731 ) This raises questions about the link between COVID-19 epidemic and wildlife.
  

Recombination Mechanism – Brief
Description :-
   A virus more closer to SARS-CoV-2 had been discovered in pangolins. With 99% of genomic concordance reported, this suggested pangolins as the most likely reservoir for this virus. However, a recent study under review shows that the genome of the coronavirus isolated from the Malaysian pangolin (Manis javanica) is less similar to SARS-CoV-2, with only 90% of genomic concordance. This indicates that the virus isolated in the pangolin is not responsible for the COVID-19 epidemic which is escalating currently. The coronavirus isolated from pangolin is similar at 99% in a specific region of the S protein, which corresponds to the 74 amino acids involved in the ACE 2 (Angiotensin Converting Enzyme 2) receptor binding domain, the one that allows the virus to enter human cells causing infection. In addition to this, RaTG13, isolated from a bat of the species Rhinolophus affinis collected in China’s Yunan Province, has recently been described as very similar to SARS-CoV-2, with genome sequences identical to 96%. These results indicate that bats, and in particular, species of the genus Rhinolophus, constitute the reservoir of the SARS-CoV-2 viruses.
  

These genomic comparisons reveal that the SARS-CoV-2 virus is the result of a recombinant between two different viruses, one close to RaTG13 and the other closer to the pangolin virus. In simple words, it is a collaboration of two pre-existing viruses.
   Anyway, there remains two inherent and unanswered questions until now.
1) In which animal did this
     recombination occur?
2) Under what conditions does this 
     recombination occur?
Scientists are in a quest to answer these questions.
  

Misconception About The Origin :-
   There is a wide misconception among many of the people about corona virus origin. Many suppose it to be created in laboratory. But this proposition is to be rejected due to the absence of evidences for this claim. On the contrary, some researchers put forth the evidence for natural evolution.
  

Evidences For Natural Evolution :-   
Evidences for natural evolution of SARS-CoV-2 can be found in various research papers. “The proximal origin of SARS-CoV-2” is one among them. Its one of the main authors, Kristian Anderson, PhD, associate professor of immunology & microbiology at Scripps Research, asserts that :- “By comparing the available genome sequence data for known coronavirus strains, we can firmly determine that SARS-CoV-2 originated through natural processes.” The RBD (Receptor Binding Domain) portion of the SARS-CoV-2 spike proteins had evolved to effectively target a molecular feature on the outside of human cells called ACE 2, a receptor involved in regulating blood pressure. Why this is a proof of natural selection? Because, SARS-CoV-2 spike protein was so effective at binding the human cells. There is also another evidence to support this claim. If someone were seeking to engineer a new coronavirus as a pathogen (for say, biological war), they would construct it from the molecular structure of the virus which is known to cause illness. But SARS-CoV-2 molecular structure differs significantly from the known coronaviruses. By demonstrating these two features of the virus, Anderson asserts that :- “These two features of the virus, the mutations in the RBD portion of the spike protein and it’s distinct molecular structure, rules out laboratory manipulation as a potential origin for SARS-CoV-2.”
  

When scientists are undertaking a huge effort to treat such an escalating pandemic by trying to detect it’s origin, it is an anti-social act to spread rumours on the basis of some fallacies. So, it is our obligation to obey the instructions given by the medical researchers and other health officers to eradicate such a deadly pandemic from our planet.