There is no clarity on the natural origin of SARS CoV-2 as no intermediate host has been found yet that transmits it from bats to humans. On the other hand, there are circumstantial evidences to suggest a laboratory origin based on the fact that the gain of function research (that induces artificial mutations in the वाइरस through repeated passaging of वायरस in human cell lines), was being carried out in the laboratory
COVID-19 disease caused by SARS CoV-2 वाइरस has caused unprecedented damage to the entire ग्रह न केवल आर्थिक रूप से बल्कि लोगों पर मनोवैज्ञानिक प्रभाव भी पड़ा है जिससे उबरने में काफी समय लगेगा। नवंबर/दिसंबर 2019 में वुहान में इसके फैलने के बाद से, इसकी उत्पत्ति के संबंध में कई सिद्धांत सामने रखे गए हैं। सबसे आम का तात्पर्य गीले बाज़ार से है वुहान जहां वाइरस jumped species from bats to humans via an intermediate host, due to its zoonotic nature of transmission as was seen in SARS (bats to civets to humans) and MERS (bats to camels to humans) वायरस1,2. However, in the past year or so, there has been no clarity on the intermediate host for the SARS CoV2 वाइरस. The other theory refers to the accidental leak of the virus from the Wuhan Institute of Virology (WIV) where the scientists were performing research on coronaviruses. In order to understand why the latter theory has gained significant popularity over the past year or so, one needs to dwell back into the events of the recent past, beginning 2011, to examine the nature of origin of such coronaviruses that could cause disease in humans.
वर्ष 2012 में, दक्षिणी चीन (युन्नान प्रांत) में एक चमगादड़ से प्रभावित तांबे की खदान में काम करने वाले छह खनिक एक बल्ले से संक्रमित हो गए थे। कोरोना3, known as RaTG13. All of them developed symptoms exactly like COVID-19 symptoms and only three of them survived. The viral samples were taken from these miners and submitted to the Wuhan Institute of Virology, the only level 4 biosecurity lab in China that was studying bat कोरोनावाइरस. Shi Zheng-Li and colleagues from the WIV have been researching on the SARS CoV वायरस इस तरह के कोरोनावायरस की उत्पत्ति को बेहतर ढंग से समझने के प्रयास में चमगादड़ों से4. यह परिकल्पना की गई है कि WIV ने कार्य अनुसंधान का लाभ उठाया5, that involved serial passaging of these वायरस in vitro and in vivo in a bid to increase their pathogenicity, transmissibility, and antigenicity. This gain of function research is very different than genetically engineering the वायरस to be more deadly in terms of their disease-causing ability. The idea behind funding and performing gain of function research is to remain a step ahead of वायरस to understand their infectivity in humans so that we are better prepared as a human race should such eventuality arises.
Thus, it is likely that the virus SARS CoV-2 made an accidental escape when it appeared in late 2019 in the city of Wuhan, although there is no concrete evidence of the same. The closest relative of this वाइरस was RaTG13 that was sampled from Yunnan miners. RaTG13 is not the backbone of SARS CoV-2 thereby refuting the theory that SARS-CoV-2 had been genetically engineered. However, the sampling of related SARS वायरस for performing research and subsequent gain of function research (leads to induced mutations) perhaps led to the development of SARS CoV-2. Gain of function does not involve genetic manipulation via genetic engineering. The genome sequencing of the new वाइरस obtained from initial 5 patients that contracted COVID-19 showed that this virus was 79.6% identical to SARS virus6.
Initially, the scientific world thought that the SARS CoV-2 वाइरस had jumped from animal species (bats) to an intermediate host and then to humans7 as was the case with SARS and MERS वायरस as mentioned above. However, the inability of finding an intermediate host for the past 18 months has led to the conspiracy theory8 कि वाइरस could have been accidentally leaked from the lab. It is also possible that the SARS CoV-2 वाइरस came from the repository of वायरस already held in WIV9 जैसा वाइरस was already well adapted to infect human cells. Had it been of a natural origin, it would have taken some time to cause the degree of transmissibility and lethality that it did.
It still remains uncertain as to whether SARS CoV-2 had a natural origin or was man-made (gain of function leading to artificially induced mutations) which accidentally escaped from the laboratory. There is no hard evidence to support either of the theories. However, based on the fact that we haven’t been able to find an intermediate host for zoonotic transmission of this वाइरस coupled with the fact that the वाइरस was well adapted already to cause infection in human cells to a great extent and the associated research at WIV in Wuhan where the वाइरस originated, suggests that it is a product of gain of function research which escaped from the lab.
Further evidence and investigation are required to establish a conclusive evidence not only to understand the origin of SARS-CoV2 वाइरस but also to ameliorate any such future accidents should they possibly arise in order to save mankind from the wrath of such viruses.
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संदर्भ
- लियू, एल।, वांग, टी। और लू, जे। छह मानव कोरोनविर्यूज़ की व्यापकता, उत्पत्ति और रोकथाम। विरोलो. पाप। 31, 94-99 (2016)। https://doi.org/10.1007/s12250-015-3687-z
- शि, जेडएल, गुओ, डी. एंड रोटियर, पीजेएम कोरोनावायरस: महामारी विज्ञान, जीनोम प्रतिकृति और उनके मेजबान के साथ बातचीत। विरोलो. पाप। 31, 1-2 (2016)। https://doi.org/10.1007/s12250-016-3746-0
- जीई, एक्सवाई।, वांग, एन।, झांग, डब्ल्यू। एट अल. एक परित्यक्त खदान में कई बैट कॉलोनियों में कई कोरोनावायरस का सह-अस्तित्व। विरोलो. पाप। 31, 31-40 (2016)। https://doi.org/10.1007/s12250-016-3713-9
- हू बी, ज़ेंग एलपी, यांग एक्सएल, जीई एक्सवाई, झांग डब्ल्यू, ली बी, ज़ी जेजेड, शेन एक्सआर, झांग वाईजेड, वांग एन, लुओ डीएस, झेंग एक्सएस, वांग एमएन, दासज़क पी, वांग एलएफ, कुई जे, शी जेडएल . बैट सार्स से संबंधित कोरोनविर्यूज़ के एक समृद्ध जीन पूल की खोज सार्स कोरोनावायरस की उत्पत्ति में नई अंतर्दृष्टि प्रदान करती है। पीएलओएस पैथोग। 2017 नवंबर 30;13(11):e1006698। दोई: https://doi.org/10.1371/journal.ppat.1006698. पीएमआईडी: 29190287; पीएमसीआईडी: पीएमसी5708621।
- विनीत डी. मेनाचेरी एट अल, "एक सार्स जैसा क्लस्टर ऑफ सर्कुलेटिंग बैट कोरोनविर्यूज़ मानव उभरने की क्षमता दिखाता है," नेट मेड। 2015 दिसंबर; 21(12):1508-13. डीओआई: https://doi.org/10.1038/nm.3985.
- झोउ, पी।, यांग, एक्सएल।, वांग, एक्सजी। एट अल. संभावित चमगादड़ मूल के एक नए कोरोनावायरस से जुड़ा निमोनिया का प्रकोप। प्रकृति 579, 270-273 (2020)। डीओआई: https://doi.org/10.1038/s41586-020-2012-7
- कैलिशर सी, कैरोल डी, कोलवेल आर, कॉर्ली आरबी, दासज़क पी एट अल। COVID-19 का मुकाबला करने वाले चीन के वैज्ञानिकों, सार्वजनिक स्वास्थ्य पेशेवरों और चिकित्सा पेशेवरों के समर्थन में वक्तव्य। वॉल्यूम 395, अंक 10226, E42-E43, मार्च 07, 2020 डीओआई: https://doi.org/10.1016/S0140-6736(20)30418-9
- रासमुसेन, एएल SARS-CoV-2 की उत्पत्ति पर। नेट मेड 27, 9 (2021)। https://doi.org/10.1038/s41591-020-01205-5.
- वुहान इंस्टीट्यूट ऑफ वायरोलॉजी, CAS, "एशिया के सबसे बड़े वायरस बैंक पर एक नज़र डालें," 2018, http://english.whiov.cas.cn/ne/201806/t20180604_193863.html.
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