Police have lodged a case of fraud, criminal breach of trust, and criminal conspiracy under IPC sections. Researchers at the Pune-based Indian Council of Medical Research-National Institute of Virology have shown that the UK variant of SARS-CoV-2, when injected into hamsters, showed high viral RNA shedding through nasal secretions and a significant body weight loss with mild lung problems as compared to the D614G variant.
The study, ‘Comparison of the pathogenicity and virus shedding of SARS CoV-2 VOC 202012/01 and D614G variant in hamster model’, was published online on February 25 on bioRxiv.org – the preprint server for Biology.
Considering the worldwide concern and speculation of the high transmission and disease severity related to the UK variant of SARS-CoV2 virus, NIV researchers assessed the disease severity and virus shedding pattern in hamsters.
The NIV had earlier isolated and cultured the UK variant of SARS-CoV2 virus from the clinical specimens of UK returnees.
There was a significantly higher per cent body weight loss in hamsters infected with the UK variant compared to D614G variant, indicating its pathogenicity. There is also a delay in clearance of the viral load in the UK variant as compared to the earlier strain. However, lung histopathological changes were not severe. There was no difference in the neutralisation potential against the D614G variant, researchers said in the study.
Initially, SARS-CoV-2 strains with D614G mutation in the spike glycoprotein became predominant worldwide. This strain was associated with higher viral loads in the upper respiratory tract than the earlier strains but didn’t produce severe disease.
Various new SARS-CoV-2 variants have been reported worldwide that are of serious concern.
The high mutation rate in RNA viruses helps them swiftly adapt to diverse environmental conditions, posing a greater challenge in their prevention and control.
Recently, various viral strains of SARS-CoV-2 with mutations of concern, like VOC 202012/01 (B.1.1.7 lineage) from the United Kingdom, VOC 202012/02 (B.1351 lineage) from South Africa, VOC 202101/02 (P.1) from Brazil, VOC 202102/02 , a B.1.1.7 cluster with E484K mutation from the United Kingdom were reported.
Among these, VOC 202012/01 (B.1.1.7 lineage) from the UK, defined by a range of 23 mutations, resulting in amino acid changes and three deletions in the virus, has spread to 94 countries as of February 16 with local transmission in at least 47 countries.
While investigations are ongoing to determine if these variants are associated with any changes in the severity of disease and transmission, this is the first study that studied the pattern of the virus shedding of this new variant compared to the earlier SARS-CoV-2 D614G variant.
Dr Pragya D Yadav, NIV scientist, is the senior researcher of the study.