The protection quest is a primary key to sharing the neutralizing antibody response to cover against all emerging VOCs based on BIV1-CovIran studies

Over time, the antigenic evolution of emerging variants of SARS-CoV-2 has demanded the development of potential protective vaccines. Administration of additional doses of current vaccines based on the WT spike protein may boost immunity, but their effectiveness has dwindled for patients with more recent variants. Here, we studied the neutralization activity of post-WT strain-based vaccination and a structural simulation in-silico based on the interactions of the RBD-hACE2 as the key to initiating infection among the VOCs of SARS-CoV-2. Our data display shows that WT sera showed a markedly greater reduction in Delta and Omicron, suggesting that the Wuhan-based vaccines may be more susceptible to breakthrough and new VOCs. According to the MD simulation, mutations of Omicron result in a significant change in the variant charge distribution throughout the binding interface that consequently alters the critical interface electrostatic potential in comparison to other variants. This observation provides new insights into immunization policy and next-generation vaccine development. Graphical abstract Image 1

Assessment of BIV1-CovIran inactivated vaccine-elicited neutralizing antibody against the emerging SARS-CoV-2 variants of concern.

OBJECTIVES: The BIV1-CovIran vaccine is highly effective against COVID-19. The neutralizing potency of all SARS-CoV-2 vaccines seems to be decreased against variants of concern. We assessed the sensitivity of the Alpha (B.1.1.7), Beta (B.1.351), and Delta (B.1.617.2) variants to neutralizing antibodies (NAbs) present in sera from individuals who had received the BIV1-CovIran candidate vaccine compared with an original Wuhan-related strain. METHODS: The ability of vaccine serum to neutralize the variants was measured using the conventional virus neutralization test. The correlation of spike (S) protein antibody and anti-receptor binding domain with neutralizing activity was investigated. RESULTS: The current study demonstrated that 29 of 32 (90.6%; 95% CI: 75.0-98.0) of the vaccinees developed NAbs against a Wuhan-related strain. It is noteworthy that 28 (87.50%) and 24 of 32 (75%) of the recipients were able to produce NAbs against Alpha, Beta, and Delta variants, respectively. Serum virus-neutralizing titres for different SARS-CoV-2 strains were weakly correlated with anti-receptor binding domain antibodies (Spearman r = 36-42, p < 0.05), but not S-binding antibodies (p > 0.05). DISCUSSION: Although there was a reduction in neutralization titres against the Alpha, Beta, and Delta variants compared with the Wuhan strain, BIV1-CovIran still exhibited potent neutralizing activity against the SARS-CoV-2 variants of concern.

Genomic and serological assessment of asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections in child labor.

Since working children have limited access to testing and monitoring for COVID-19, we decided to measure SARS-CoV-2 prevalence among them and compare it to non-working children. Our objective is to compare the frequency of SARS-CoV-2 genome and anti-SARS-CoV-2 antibody among working and non-working children. Volunteer child labor studying at Defense of Child Labor and Street Children and randomly selected 5-18-year-old (same range as child labor group) unemployed children participated in this study. The groups, respectively, had 65 and 137 members. This is an analytical cross-sectional study that surveys molecular prevalence of SARS-CoV-2 infection by RT-PCR, and seroprevalence of SARS-CoV-2 antibody by ELISA in working and non-working children. The IBM SPSS statistics software version 25 was used for data analysis. The χ2 or Fisher's exact test was used to analyze categorical dependent variables, for calculating odds ratios and 95% confidence intervals. Among the children enrolled in this study, molecular prevalence of SARS-CoV-2 turned out to be 18.5% in working children while it was 5.8% in unemployed children [aOR: 3.00 (CI95%: 1.00-7.00); P value: 0.003] and seroprevalence turned out to be 20% in working children vs 13.9% in non-working children [aOR: 1.000 (CI95%: 0.00-2.00); > P 0.001]. Equal SARS-CoV-2 viral load as adults and no symptoms or mild ones in children, coupled with working children's strong presence in crowded areas and their higher rate of COVID-19 prevalence, make them a probable source for spread of the virus.