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COVID-19 has brought the world to a standstill with a wave of destruction in country after country with tremendous loss of lives and livelihood in advanced to developing nations. Whole world is staring at the prospect of repeated lockdowns with another wave of COVID-19 predicted to hit the world in September of 2020. The second wave is assumed to be even more destructive with severe impact across much of the world. The only way to defeat this pandemic is to quickly develop a safe and effective vaccine against this raging menace and initiate a global vaccination drive. Our study is an attempt to deploy various computational methods to identify B-cell and T-cell epitopes from the spike surface glycoprotein of SARS-COV-2 which have the novel potential for vaccine development against COVID-19. For this we have taken 8 unique strains with one each from India, China, France, USA, Italy, Australia, Iran and Pakistan. The strain data was extracted from NCBI Database. By analyzing the immune parameters like surface accessibility, antigenicity, variability, conservancy, flexibility, hydrophilicity, allergenicity and toxicity of the conserved sequences of spike glycoprotein using various databases and bioinformatics tools, we identified two potential novel linear (SGTNGTKRFDN and ASVYAWNRK) and one structural B-cell epitope as well as two T-cell epitopes (RLFRKSNLK and IPTNFTISV) which can be used as epitope-based peptide vaccines. Docking simulation assay revealed that above T-cell epitopes have minimum free binding energy and showed strong hydrogen bond interaction which strengthened its potential as being a T-cell epitope for the epitope-based novel vaccine against SARS-CoV-2. This study allows us to claim that B-cell and T-cell epitopes mentioned above provide potential pathways for developing an exploratory vaccine against spike surface glycoprotein of SARS-CoV-2 with high confidence for the identified strains. We will need to confirm our findings with biological assays., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: In recent years, several avian influenza subtypes (H5, H7 and H9) have transmitted directly from birds to man, posing a pandemic threat., Objectives: We have investigated the immunogenicity and protective efficacy of a cell based candidate pandemic influenza H7 vaccine in pre-clinical animal models., Methods: Mice and ferrets were immunised with two doses of the split virus vaccine (12-24 microg haemagglutinin) with or without aluminium hydroxide adjuvant and challenged 3 weeks after second dose with the highly pathogenic A/chicken/Italy/13474/99 (H7N1) virus. The H7N1-specific serum antibody response was also measured. After challenge, viral shedding, weight loss, disease signs and death (only mice) were recorded., Results: Low-to-modest serum antibody titres were detected after vaccination. Nevertheless, the vaccine induced significant protection from disease after challenge with the wild-type virus. In the murine lethal challenge model, vaccination effectively prevented death and, furthermore, formulation with adjuvant reduced excessive weight loss and viral shedding. In ferrets, vaccination reduced viral shedding and protected against systemic spread of the virus., Conclusions: We have extended to the H7 subtype the finding that protective efficacy may not be directly correlated with the pre-challenge levels of serum antibodies, a finding which could be of great importance in assessing the potential effectiveness of pandemic influenza vaccines.

A randomised, open study was carried out among an elderly population in order to compare the reactogenicity and immunogenicity of an inactivated, split virion influenza vaccine (Vaxigrip, Aventis Pasteur MSD, Lyon, France) with that of an MF59-adjuvanted, subunit vaccine (Fluad, Chiron Vaccines, Siena, Italy). Both vaccines contained the three strains: A/Sydney/5/97 (H3N2), A/Beijing/262/95 (H1N1) and B/Beijing/184/93, recommended by the WHO for the 1998-1999 influenza season. A total of 2150 subjects were vaccinated and included in the reactogenicity analysis. A total of 1076 subjects received Vaxigrip (age 73.3 +/- 5.9 years, 49.6% men) and 1074 subjects received Fluad (age 73.4 +/- 5.9 years, 52.3% men). All subjects were kept under medical observation for 30 min after vaccination, in order to check any immediate local and/or systemic reaction. A self monitoring diary card was given to all subjects to collect any local and/or systemic reaction occurring during the 3 days following the vaccination, any adverse event occurring between vaccination day and 21st day post-vaccination and any medication taken during the study period. A total of 1186 subjects were included in the immunogenicity analysis. A total of 591 subjects received Vaxigrip (age 73.4 +/- 5.6 years, 52.3% men) and 595 subjects received Fluad (age 73.8 +/- 5.9 years, 55.8% men). Blood samples were collected pre- and 21 days post-vaccination and were analysed by the haemagglutination inhibition assay. In terms of reactogenicity both vaccines were generally well tolerated. The frequency of local reactions was lower in the group that received Vaxigrip. Pain at the injection site occurring from 30 min to 3 days after vaccination was also significantly less frequent (P = 0.005) in the Vaxigrip group. Fever > or =37.5 degrees C was reported in less than 1% of all vaccinated subjects. No serious adverse event was related to vaccine administration. In terms of immunogenicity both vaccines induced an effective immune response (anti-HI titre > or =40) against A/Sydney/5/97 (H3N2) and A/Beijing/262/95 (H1N1) strains in the entire population. Vaxigrip and Fluad induced similar seroprotection and seroconversion rates against the A/Sydney/5/97 (H3N2) strain. For both vaccines a lower percentage of subjects achieved a seroprotective titre > or =40 against the B/Beijing/184/93. A lower antibody response against the influenza B strain was also observed in other studies conducted during the same season. In subjects 75 years of age or older, Fluad was more immunogenic than Vaxigrip for all three virus strains., (Copyright 2002 Elsevier Science Ltd.)

Three-hundred and eight outpatient elderly subjects (> or = 65 years) were randomly assigned to receive the MF59-adjuvanted influenza vaccine (FLU-AD; n = 204) or a conventional subunit influenza vaccine (AGRIPPAL S1; n = 104) in order to compare the safety and immunogenicity of the two vaccines. Although mild pain at the injection site was reported more frequently by subjects immunised with the adjuvanted vaccine, both vaccines were shown to be safe and well tolerated. The adjuvanted vaccine was more immunogenic as indicated by higher post-immunisation geometric mean titres (GMTs) and by higher proportions of subjects with post-immunisation > or = four fold increases of antibody titres or subjects with > or = 1/160 post-immunisation HI titres. These differences, statistically significant for all three strains after immunisation, indicated that, by addition of the MF59 adjuvant emulsion, conventional subunit influenza antigens acquire an enhanced immunogenicity without any clinically significant increase of their reactogenicity.