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Shete, A. M.

Publications and source records attributed to Shete, A. M..

3 recordsLinked to original sources

Neutralization against B.1.351 and B.1.617.2 with sera of COVID-19 recovered cases and vaccinees of BBV152

Recently, multiple SARS-CoV-2 variants have been detected across the globe. The recent emergence of B.1.617 lineage has created serious public health problem in India. The high transmissibility was observed with this lineage which has led to daily increase in the number of SARS-CoV-2 infections. Apparently, the sub-lineage B.1.617.2 has slowly dominated the other variants including B1617.1, B.617.3 and B.1.1.7. With this, World Health Organization has described B.1.617.2 as variant of concern. Besides this, variant of concern B.1.351 has been also reported from India, known to showreducedefficacyfor many approved vaccines. With the increasing threat of the SARS-CoV-2 variants, it is imperative to assess the efficacy of the currently available vaccines against these variants. Here, we have evaluated the neutralization potential of sera collected from COVID-19 recovered cases (n=20) and vaccinees with two doses of BBV152 (n=17) against B.1.351 and B.1.617.2 compared to the prototype B.1 (D614G) variant.The finding of the study demonstrated a reduction in neutralization titers with sera of COVID-19 recovered cases(3.3-fold and 4.6-fold) and BBV152 vaccinees (3. 0 and 2.7 fold) against B.1.351 and B.1.617.2 respectively.Although, there is reduction in neutralization titer, the whole-virion inactivated SARS-CoV-2 vaccine (BBV152) demonstrates protective response against VOC B.1351 and B.1.617.2.

microbiology

SARS CoV-2 variant B.1.617.1 is highly pathogenic in hamsters than B.1 variant

BackgroundThe recent emergence of new SARS-CoV-2 lineage B.1.617 in India has been associated with a surge in the number of daily infections. This variant has combination of specific mutations L452R, E484Q and P681R reported to possibly enhance the transmissibility with likelihood of escaping the immunity. We investigated the viral load and pathogenic potential of B.1.617.1 in Syrian golden hamsters. MethodsTwo groups of Syrian golden hamsters (9 each) were inoculated intranasally with SARS CoV-2 isolates, B.1 (D614G) and B.1.617.1 respectively. The animals were monitored daily for the clinical signs and body weight. The necropsy of three hamsters each was performed on 3, 5- and 7-days post-infection (DPI). Throat swab (TS), nasal wash (NW) and organ samples (lungs, nasal turbinate, trachea) were collected and screened using SARS-CoV-2 specific Real-time RT-PCR. ResultsThe hamsters infected with B.1.617.1 demonstrated increased body weight loss compared to B.1 variant. The highest viral load was observed in nasal turbinate and lung specimens of animals infected with B.1.167.1 on 3 DPI. Neutralizing antibody (NAb) and IgG response in hamsters of both the groups were observed from 5 and 7 DPI respectively. However, higher neutralizing antibody titers were observed against B.1.167.1. Gross pathology showed pronounced lung lesions and hemorrhage with B.1.671 compared to B.1. ConclusionsB.1617.1 and B.1 variant varied greatly in their infectiousness, pathogenesis in hamster model. This study demonstrates higher pathogenicity in hamsters evident with reduced body weight, higher viral load in lungs and pronounced lung lesions as compared to B.1 variant. SummaryB.1.617.1 is the new SARS-CoV-2 lineage that emerged in India. Maximal body weight loss and higher viral load in hamsters infected with B.1.617.1. It caused pronounced lung lesions in hamsters compared to B.1 variant which demonstrates the pathogenic potential of B.1.617.1.

microbiology

Neutralization of variant under investigation B.1.617 with sera of BBV152 vaccinees

The drastic rise in the number of cases in Maharashtra, India has created a matter of concern for public health experts. Twelve isolates of VUI lineage B.1.617 were propagated in VeroCCL81 cells and characterized. Convalescent sera of the COVID-19 cases and recipients of BBV152 (Covaxin) were able to neutralize VUI B.1.617.

immunology