Neutralizing Antibodies Titers and Side Effects in Response to BNT162b2 Vaccine in Healthcare Workers with and without Prior SARS-CoV-2 Infection

Performance of Three Anti-SARS-CoV-2 Anti-S and One Anti-N Immunoassays for the Monitoring of Immune Status and Vaccine Response

This study aimed to evaluate and compare the performance of three anti-S and one anti-N assays that were available to the project in detecting antibody levels after three commonly used SARS-CoV-2 vaccines (Pfizer, Moderna, and Johnson & Johnson). It also aimed to assess the association of age, sex, race, ethnicity, vaccine timing, and vaccine side effects on antibody levels in a cohort of 827 individuals. In September 2021, 698 vaccinated individuals donated blood samples as part of the Association for Diagnostics & Laboratory Medicine (ADLM) COVID-19 Immunity Study. These individuals also participated in a comprehensive survey covering demographic information, vaccination status, and associated side effects. Additionally, 305 age- and gender-matched samples were obtained from the ADLM 2015 sample bank as pre-COVID-19-negative samples. All these samples underwent antibody level analysis using three anti-S assays, namely Beckman Access SARS-CoV-2 IgG (Beckman assay), Ortho Clinical Diagnostics VITROS Anti-SARS-CoV-2 IgG (Ortho assay), Siemens ADVIA Centaur SARS-CoV-2 IgG (Siemens assay), and one anti-N antibody assay: Bio-Rad Platelia SARS-CoV-2 Total Ab assay (BioRad assay). A total of 827 samples (580 COVID-19 samples and 247 pre-COVID-19 samples) received results for all four assays and underwent further analysis. Beckman, Ortho, and Siemens anti-S assays showed an overall sensitivity of 99.5%, 97.6%, and 96.9%, and specificity of 90%, 100%, and 99.6%, respectively. All three assays indicated 100% sensitivity for individuals who received the Moderna vaccine and boosters, and over 99% sensitivity for the Pfizer vaccine. Sensitivities varied from 70.4% (Siemens), 81.5% (Ortho), and 96.3% (Beckman) for individuals who received the Johnson & Johnson vaccine. BioRad anti-N assays demonstrated 46.2% sensitivity and 99.25% specificity based on results from individuals with self-reported infection. The highest median anti-S antibody levels were measured in individuals who received the Moderna vaccine, followed by Pfizer and then Johnson & Johnson vaccines. Higher anti-S antibody levels were significantly associated with younger age and closer proximity to the last vaccine dose but were not associated with gender, race, or ethnicity. Participants with higher anti-S levels experienced significantly more side effects as well as more severe side effects (e.g., muscle pain, chills, fever, and moderate limitations) (p < 0.05). Anti-N antibody levels only indicated a significant correlation with headache. This study indicated performance variations among different anti-S assays, both among themselves and when analyzing individuals with different SARS-CoV-2 vaccines. Caution should be exercised when conducting large-scale studies to ensure that the same platform and/or assays are used for the most effective interpretation of the data.

SARS-CoV-2 S-RBD IgG & Neutralizing antibodies among different categories of health care workers post third dose BNT162b2 mRNA COVID-19 vaccine

Neutralizing antibodies (NTAb) play a significant role in preventing and protecting against SARS-CoV-2 virus infection. Identifying NTAb is undoubtedly imperative in understanding the immunity toward COVID-19 better. However, it is interesting to note that the production of NTAb varies among individuals, especially among healthcare workers (HCWs), as they are exposed to the virus daily. Hence, we would like to investigate factors affecting the production of S-RBD IgG and NTAb among different categories of HCWs, particularly after receiving the third dose of the BNT162b2 mRNA COVID-19 Vaccine. A total of 361 HCWs from our hospital were prospectively enrolled and had their S-RBD IgG and NTAb titers measured. They were studied in relation to the degree of exposure to COVID-19, breakthrough infections, gender, age, race, household income, housing type, household number, and education levels. HCWs with the highest risk of exposure to COVID-19, breakthrough infections, and male gender displayed the highest median titers of both S-RBD IgG and NTAb, and the differences were statistically significant (p < .05). Age, race, household income, housing type, household number, and education levels were revealed to be insignificant. We concluded that the degree of exposure to COVID-19, breakthrough infections, and male gender are significant factors in NTAb production among HCWs.

Drug Cocktail Formulation via Circuit Design

Electronic circuits intuitively visualize and quantitatively simulate biological systems with nonlinear differential equations that exhibit complicated dynamics. Drug cocktail therapies are a powerful tool against diseases that exhibit such dynamics. We show that just six key states, which are represented in a feedback circuit, enable drug-cocktail formulation: 1) healthy cell number; 2) infected cell number; 3) extracellular pathogen number; 4) intracellular pathogenic molecule number; 5) innate immune system strength; and 6) adaptive immune system strength. To enable drug cocktail formulation, the model represents the effects of the drugs in the circuit. For example, a nonlinear feedback circuit model fits measured clinical data, represents cytokine storm and adaptive autoimmune behavior, and accounts for age, sex, and variant effects for SARS-CoV-2 with few free parameters. The latter circuit model provided three quantitative insights on the optimal timing and dosage of drug components in a cocktail: 1) antipathogenic drugs should be given early in the infection, but immunosuppressant timing involves a tradeoff between controlling pathogen load and mitigating inflammation; 2) both within and across-class combinations of drugs have synergistic effects; 3) if they are administered sufficiently early in the infection, anti-pathogenic drugs are more effective at mitigating autoimmune behavior than immunosuppressant drugs.

Ruxolitinib treatment in myelofibrosis and polycythemia vera causes suboptimal humoral immune response following standard and booster vaccination with BNT162b2 mRNA COVID-19 vaccine

Patients affected by myelofibrosis (MF) or polycythemia vera (PV) and treated with ruxolitinib are at high risk for severe coronavirus disease 2019. Now a vaccine against the virus SARS-CoV-2, which is responsible for this disease, is available. However, sensitivity to vaccines is usually lower in these patients. Moreover, fragile patients were not included in large trials investigating the efficacy of vaccines. Thus, little is known about the efficacy of this approach in this group of patients. In this prospective single-center study, we evaluated 43 patients (30 MF patients and 13 with PV) receiving ruxolitinib as a treatment for their myeloproliferative disease. We measured anti-spike and anti-nucleocapsid IgG against SARS-CoV2 15-30 days after the second and the third BNT162b2 mRNA vaccine booster dose. Patients receiving ruxolitinib showed an impaired antibody response to complete vaccination (2 doses), as 32.5% of patients did not develop any response. After the third booster dose with Comirnaty, results slightly improved, as 80% of these patients produced antibodies above the threshold positivity. However, the quantity of produced antibodies was well below that reached than those reported for healthy individuals. PV patients elicited a better response than patients affected by MF. Thus, different strategies should be considered for this high-risk group of patients.

Homologous booster immunization with an inactivated vaccine induced robust antibody response in healthcare workers: A retrospective study

Coronavirus Disease 2019 (Covid-19) severely impacted the health, society, and economy around the world. With declining protective efficacy of primary vaccination and the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants, a Covid-19 booster vaccination is being fully implemented globally. Many people received three doses of BBIBP-CorV inactivated vaccine in China and other developing countries. However, the antibody response and immune persistence of the homologous BBIBP-CorV booster vaccination is yet to be thoroughly evaluated, as previous studies focused within one month after the third dose. In this study, 97 participants were enrolled to analyze the antibody response and immune persistence within 6 months as well as the safety within 7 days after the third-dose of homologous BBIBP-CorV inactivated vaccine. The seroconversion rate for total antibody against the receptor binding domain (RBD) of the SARS-CoV-2 spike (S) protein were both 100% at month 1 and month 6 after the third dose. The IgG against the RBD of the SARS-CoV-2 S protein seroconversion rate increased from 42.27% before the third dose to 100% 1 month after the third dose and then slightly decreased to 98.97% 5 months later. Positive IgM against the RBD of the SARS-CoV-2 S protein was rare and was observed in only one participant at month 1 after the third dose. The neutralizing antibody levels at month 1 and month 6 after the third dose increased 63.32-fold and 13.16-fold compared with those before the third dose, and the positive rate for neutralizing antibody was still 100% at month 6 after the third dose. Importantly, the antibody responses induced by the vaccine and immune persistence were not affected by sex or age. No serious adverse reactions were reported. Total antibody and IgG against the RBD of the SARS-CoV-2 S protein were highly correlated with neutralizing antibody, suggesting that total antibody and IgG against the RBD of the SARS-CoV-2 S protein could be used as predictors for neutralizing antibody. In conclusion, the third dose of homologous BBIBP-CorV inactivated vaccine induced a robust antibody response and moderate immune persistence. These finding are of great significance for development future vaccination strategies.

Comparison of three different COVID-19 vaccine platforms (CoronaVac, BTN162b2, and Ad5-nCoV) in individuals with and without prior COVID-19: Reactogenicity and neutralizing antibodies

Neutralizing antibodies (NAbs) can be indicators of collective immunity, vaccine efficacy, and the longevity of the humoral response. This study aimed to compare reactogenicity and NAbs generated by three different COVID-19 vaccine platforms in individuals with and without prior COVID-19. 336 individuals vaccinated (112 with CoronaVac [inactivated virus], 112 with BNT162b2 [messenger RNA], and 112 with Ad5-nCoV [non-replicating viral vector]) were included. NAbs were quantified with the cPass SARS-CoV-2 kit. Individuals immunized with the Ad5-nCoV showed higher reactogenicity than those immunized with the other vaccines (p < 0.001). The BTN162b2 vaccine-induced NAbs with higher inhibition capacity than the other platforms in the first dose. In individuals without prior COVID-19, the Ad5-nCoV vaccine generated lower NAbs against SARS-CoV-2 than those induced by two doses of the BTN162b2 (Ad5-nCoV 72.10 [55.6-93.4] vs. BTN162b2 98.41 [98.16-98.56], p < 0.0001). One individual did not generate NAbs (0.89%) after a complete immunization with CoronaVac; in BTN162b2, all generated these antibodies, and in the Ad5-nCoV group, four individuals (3.57%) did not generate NAbs. Comorbidities, gender, age, and reactogenicity did not significantly influence the generation of NAbs (p > 0.05); however, a history of COVID-19 before vaccination was associated with antibodies with greater neutralizing capacity after the first dose (p < 0.01). In conclusion, the mRNA vaccine (BTN162b2) had a remarkable better ability to produce NAbs and lower reactogenicity than the other platforms, whereas the Ad5-nCov vaccine induced the lowest NAbs response in individuals without a history of COVID-19; therefore, we suggest that a booster could benefit these individuals.

A pseudovirus-based platform to measure neutralizing antibodies in Mexico using SARS-CoV-2 as proof-of-concept

The gold-standard method to evaluate a functional antiviral immune response is to titer neutralizing antibodies (NAbs) against a viral pathogen. This is historically performed using an in vitro assay of virus-mediated infection, which requires BSL-3 facilities. As these are insufficient in Latin American countries, including Mexico, scant information is obtained locally about viral pathogens NAb, using a functional assay. An alternative solution to using a BSL-3 assay with live virus is to use a BSL-2-safe assay with a non-replicative pseudovirus. Pseudoviral particles can be engineered to display a selected pathogen's entry protein on their surface, and to deliver a reporter gene into target cells upon transduction. Here we comprehensively describe the first development of a BSL-2 safe NAbs-measuring functional assay in Mexico, based on the production of pseudotyped lentiviral particles. As proof-of-concept, the assay is based on Nanoluc luciferase-mediated luminescence measurements from target cells transduced with SARS-CoV-2 Spike-pseudotyped lentiviral particles. We applied the optimized assay in a BSL-2 facility to measure NAbs in 65 serum samples, which evidenced the assay with 100% sensitivity, 86.6% specificity and 96% accuracy. Overall, this is the first report of a BSL-2 safe pseudovirus-based functional assay developed in Mexico to measure NAbs, and a cornerstone methodology necessary to measure NAbs with a functional assay in limited resources settings.

Immunogenicity of BNT162b2 mRNA-Based Vaccine against SARS-CoV-2 in People with Cystic Fibrosis According to Disease Characteristics and Maintenance Therapies

During the SARS-CoV-2 vaccination campaign, people with CF (pwCF) were considered a clinically vulnerable population. However, data on the immunogenicity of anti-SARS-CoV-2 vaccines in pwCF are lacking. We conducted a prospective study enrolling all patients aged > 12 and who were followed-up in our CF center and received two doses of the BNT162b2 vaccine in the period of March−October 2021. Blood samples were taken from them for the quantification of antibodies to the SARS-CoV-2 spike protein receptor binding domain immediately before receiving the first dose and 3 and 6 months after the second dose. We enrolled 143 patients (median age: 21 years, range: 13−38), 16 of whom had had a previous infection. Geometric mean antibody titer (GMT) 3 months after vaccination was 1355 U/mL (95% CI: 1165−1575) and decreased to 954 U/mL (95% CI: 819−1111) after 6 months (p < 0.0001). GMT was higher among previously infected patients as compared to those naïve to SARS-CoV-2 (6707 vs. 1119 U/mL at 3 months and 4299 vs. 796 U/mL at 6 months, p < 0.0001) with no significant differences in the rate of decline over time (p = 0.135). All pwCF mounted an antibody response after two doses of the BNT162b2 vaccine, which waned at 6 months from vaccination. Age ≥ 30 years and the use of inhaled corticosteroids were associated with a lower humoral response. Between the second and the third doses, nine episodes of vaccine breakthrough infections were observed.

Long-term antibody response following SPUTNIK V primary vaccination in healthcare workers with and without history of SARS-CoV-2 infection: Prospective cohort study from a hospital in Argentina

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After completing a two-dose Sputnik V schedule, all vaccinees developed antibodies.

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Prior infection was associated with higher antibody concentrations.

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Antibodies decreased significantly after 6 months in naïve subjects.

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In subjects without infection, 17% were negative at day 180.

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SARS-CoV2 infection after vaccination increased antibody concentrations.

Background

In December 2020, Sputnik V was incorporated to the National COVID-19 Immunization Plan in Argentina. Studies had shown 98% of antibody response rate. To date, data on immunogenicity and antibody persistence in Argentina are scarce.

The objective was to assess humoral immune response after two doses of Sputnik V in Health Care Workers (HCWs) at the Ricardo Gutierrez Children’s Hospital (RGCH).

Methods

A prospective, cohort study in HCWs immunized with two doses of Sputnik V between February and March 2021. The following variables were assessed: age, gender, risk factors for severe COVID-19 or mortality, immunosuppressive therapy and history of SARS-CoV-2. Blood samples were drawn on the day of the first dose, 28 days and 180 days after the second. Anti-Spike IgG was measured using an ELISA assay. Differences in immune response were evaluated according to study variables. Comparison analyses between groups with or without history of infection were performed, with T-test and ANOVA or Mann-Whitney tests. For each subject, we compared baseline values with 28 days and 180 days after the second vaccine.

STATA version 14 and R Sofware were used for data analyses.

Results

We included 528 individuals, mean age 41.5 years, 82.9% female, 14.4% (76/528) reported previous SARS-CoV-2 infection.

All subjects developed antibodies post-vaccination. At day 28, concentrations were significantly higher in previously infected than naïve subjects (p < 0.001) with no differences according to age, gender and comorbidities.

At day 180, 17% (95% CI 13.17–21.53) of naïve subjects were negative. Antibody concentrations decreased significantly in all subjects except in those who reported SARS-CoV-2 infection after vaccination (n = 31). This last group had significantly higher antibody concentrations.

Conclusion

This study assessed immune response to a new COVID-19 vaccine in real life in a cohort of subjects. Antibody concentrations varied according to history of SARS-COV-2 infection and decreased over time.

Differences in B-Cell Immunophenotypes and Neutralizing Antibodies Against SARS-CoV-2 After Administration of BNT162b2 (Pfizer-BioNTech) Vaccine in Individuals with and without Prior COVID-19 - A Prospective Cohort Study

Purpose

Understanding the humoral immune response dynamics carried out by B cells in COVID-19 vaccination is little explored; therefore, we analyze the changes induced in the different cellular subpopulations of B cells after vaccination with BNT162b2 (Pfizer-BioNTech).

Methods

This prospective cohort study evaluated thirty-nine immunized health workers (22 with prior COVID-19 and 17 without prior COVID-19) and ten subjects not vaccinated against SARS-CoV-2 (control group). B cell subpopulations (transitional, mature, naïve, memory, plasmablasts, early plasmablast, and double-negative B cells) and neutralizing antibody levels were analyzed and quantified by flow cytometry and ELISA, respectively.

Results

The dynamics of the B cells subpopulations after vaccination showed the following pattern: the percentage of transitional B cells was higher in the prior COVID-19 group (p < 0.05), whereas virgin B cells were more prevalent in the group without prior COVID-19 (p < 0.05), mature B cells predominated in both vaccinated groups (p < 0.01), and memory B cells, plasmablasts, early plasmablasts, and double-negative B cells were higher in the not vaccinated group (p < 0.05).

Conclusion

BNT162b2 vaccine induces changes in B cell subpopulations, especially generating plasma cells and producing neutralizing antibodies against SARS-CoV-2. However, the previous infection with SARS-CoV-2 does not significantly alter the dynamics of these subpopulations but induces more rapid and optimal antibody production.

Human IgG antibody responses to severe acute respiratory syndrome coronavirus 2 viral antigens receptor-binding domain, spike, and nucleocapsid, in vaccinated adults from Merida, Mexico

Several vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been approved for controlling the coronavirus disease 2019 (COVID-19) pandemic worldwide. Antibody response is essential to understand the immune response to different viral targets after vaccination with different vaccine platforms. Thus, the main aim of this study was to describe how vaccination with two distinct SARS-CoV-2 vaccine preparations elicit IgG antibody specific responses against two antigenically relevant SARS-CoV-2 viral proteins: the receptor-binding domain (RBD) and the full-length spike (S). To do so, SARS-CoV-2 protein specific in-house enzyme-linked immunosorbent assays (ELISAs) were standardized and tested against serum samples collected from 89 adults, recipients of either a single-dose of the Spike-encoding mRNA-based Pfizer/BioNTech (Pf-BNT) (70%, 62/89) or the Spike-encoding-Adenovirus-5-based CanSino Biologics Inc. (CSBIO) (30%, 27/89) in Merida, Mexico. Overall, we identified an IgG seroconversion rate of 88% (68/78) in all vaccinees after more than 25 days post-vaccination (dpv). Anti-RBD IgG-specific responses ranged from 90% (46/51) in the Pf-BNT vaccine at 25 dpv to 74% (20/27) in the CSBIO vaccine at 42 dpv. Compared to the S, the RBD IgG reactivity was significantly higher in both Pf-BNT (p < 0.004) and CSBIO (p < 0.003) vaccinees. Interestingly, in more than 50% of vaccine recipients, with no history of COVID-19 infection, antibodies against the nucleocapsid (N) protein were detected. Thus, participants were grouped either as naïve or pre-exposed vaccinees. Seroconversion rates after 25 and more dpv varies between 100% in Pf-BNT (22/22) and 75% (9/12) in CSBIO pre-exposed vaccinees, and 89% (26/29) and 73% (11/15) in Pf-BNT and CSBIO naïve vaccine recipients, respectively. In summary, observed seroconversion rates varied depending on the type of vaccine, previous infection with SARS-CoV-2, and the target viral antigen. Our results indicate that both vaccine preparations can induce detectable levels of IgG against the RBD or Spike in both naïve and SARS-CoV-2 pre-exposed vaccinees. Our study provides valuable and novel information about the serodiagnosis and the antibody response to vaccines in Mexico.

Assessment of neutralizing antibody responses after natural SARS-CoV-2 infection and vaccination in congolese individuals

Background

Assessing immune responses after vaccination is part of the evaluation package of vaccine effectiveness in the real world. Regarding SARS-CoV-2, neutralizing antibody levels has been shown to be a good indicator of antibody immune response boosting. So far, limited data have been reported from Africa including in Central Africa. The objective of this study was to provide data on anti-S1 spike total IgG and neutralizing antibodies in vaccinated and non-vaccinated including naturally infected Congolese population during B.1.214.1 and B.1.617.2 variant waves.

Methods

Recruited patients were divided into 4 groups: (1) Naturally infected by the B.1.214.1 variant on January 2021 and followed up until September 2021. These patients have been vaccinated at month 07 and then followed up for 2 months post vaccination; (2) Naturally infected by the B.1.617.2 variant from June 2021; (3) unvaccinated SARS-CoV-2 individuals with no history of prior SARS-CoV-2 infection; (4) fully vaccinated individuals with sinopharm/BBIP-CorV or Janssen/Ad26.COV2.S. SARS-CoV-2 was detected by qRT-PCR and sequenced using Next-Generation Sequencing. ELISA method was used for detecting IgG, and neutralizing Antibody against SARS-CoV-2 antigens using commercial neutralizing assay.

Results

Individuals infected by the B.1214.1 variant elicited consistently high IgG titers at 02, 03 and 06 months. Two months post vaccination with BBIP-CorV, participants showed a significant increase by × 2.5 fold (p < 0.0001) of total IgG and X1.5 fold for neutralizing antibody capacity. This study showed that natural infection with B1.617.2 (delta) variant was more immunogenic compared to those being infected with B1.214.2 variant.

We found a significantly higher concentration in anti-SARS-CoV-2 IgG (p < 0.0002) and antibodies neutralization capacity (P < 0.0001) in fully vaccinated compared to unvaccinated participants. Two months post vaccination, individuals who received Janssen/Ad26.COV2.S presented higher (p = 0.01) total IgG to spike protein compared to BBIP-CorV.

Conclusion

Both natural infection and vaccination with BBIP-CorV and Janssen/Ad26.COV2.S induced antibody response in Congolese population. In addition, Janssen/Ad26.COV2.S was more immunogenic than Sinopharm/BBIP-CorV. There is a need to investigate the duration of these antibodies both in previously infected and naive vaccinated Congolese to allow public heath stakeholders to make evidence-based decision on vaccine schedule for the Congolese population.

Safety and Adverse Events Related to COVID-19 mRNA Vaccines; a Systematic Review

Introduction:

Knowledge of vaccine-related adverse events is crucial as they are among the most ‎important factors ‎that cause hesitation in receiving vaccines. Therefore, we aimed to systematically ‎review the adverse events ‎related to the mRNA vaccines reported in the literature.‎

Method:

A systematic literature search was carried out in the databases of Scopus, PubMed, ‎Cochrane, and Web ‎of Science. We selected original studies that explored the side effects of ‎mRNA ‎COVID-19 vaccines using a two-phase (title/abstract and full-text) screening process.‎

Results:

Cardiac ‎complications were the most commonly reported severe adverse events. It appeared that ‎systemic adverse reactions are more ‎common after the second dose of vaccines. The number of ‎adverse effects reported after the Pfizer vaccine was ‎higher than other vaccines, mostly due to its ‎earlier approval and more widespread use throughout the world. Cardiac adverse events had a ‎‎higher prevalence but no significant association has been found between COVID-19 mRNA vaccines ‎and cardiac ‎adverse events except for myopericarditis. ‎

Conclusion:

Vaccines ‎play a crucial role in controlling the COVID-19 pandemic and decreasing ‎mortalities and the results of the present ‎review acknowledge the fact that the benefits outweigh the ‎adverse events of these vaccines.‎

Adequacy of Hemodialysis Serves as an Independent Predictor of Humoral Response to ChAdOx1 Prime-Boost Vaccination in Hemodialysis Patients

Background: Immune response assessed by the quantification of neutralizing antibodies (nAbs) and predictors associated with immunogenicity after the prime-boost ChAdOx1 (Oxford−AstraZeneca) COVID-19 vaccine in hemodialysis (HD) patients remains unclear. Methods: This prospective study enrolled 174 HD patients and 67 healthy subjects to evaluate antibodies against the spike protein 1 and receptor-binding domain of severe acute respiratory syndrome coronavirus type 2 after prime-booster vaccination, by using enzyme-linked immunosorbent assay and applied spline-based generalized additive model regression analysis to predict 50% neutralization titer (NT50). The correlation between HD parameters and NT50 was analyzed. Results: NT50 was lower in HD patients compared with healthy controls after the prime-boost dose (p < 0.001). The geometric mean titer ratios were higher in first-dose seronegative than in the seropositive subgroup in HD patients and healthy controls (6.96 vs. 2.36, p = 0.002, and 9.28 vs. 1.26, p = 0.011, respectively). After two doses of ChAdOx1, one-way ANOVA showed that Ca × P was positively associated with NT50 (p trend = 0.043) and multiple linear regression showed the similar results (p = 0.021). Kt/V (a quantification of dialysis adequacy) (OR = 20.295, p = 0.005) could independently predict seroconversion (NT50 ≥ 35.13 IU/mL). Conclusion: Adequacy of hemodialysis could independently predict seroconversion in HD subjects vaccinated with prime-boost doses of ChAdOx1.

Distinct immune cell dynamics correlate with the immunogenicity and reactogenicity of SARS-CoV-2 mRNA vaccine

Two doses of Pfizer/BioNTech BNT162b2 mRNA vaccine elicit robust severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-neutralizing antibodies with frequent adverse events. Here, by applying a high-dimensional immune profiling on 92 vaccinees, we identify six vaccine-induced immune dynamics that correlate with the amounts of neutralizing antibodies, the severity of adverse events, or both. The early dynamics of natural killer (NK)/monocyte subsets (CD16+ NK cells, CD56high NK cells, and non-classical monocytes), dendritic cell (DC) subsets (DC3s and CD11c- Axl+ Siglec-6+ [AS]-DCs), and NKT-like cells are revealed as the distinct cell correlates for neutralizing-antibody titers, severity of adverse events, and both, respectively. The cell correlates for neutralizing antibodies or adverse events are consistently associated with elevation of interferon gamma (IFN-γ)-inducible chemokines, but the chemokine receptors CCR2 and CXCR3 are expressed in distinct manners between the two correlates: vaccine-induced expression on the neutralizing-antibody correlate and constitutive expression on the adverse-event correlate. The finding may guide vaccine strategies that balance immunogenicity and reactogenicity.

Anti-SARS-CoV-2S Antibody Levels in Healthcare Workers 10 Months after the Administration of Two BNT162b2 Vaccine Doses in View of Demographic Characteristic and Previous COVID-19 Infection

Antibody levels that confer full protection against SARS-CoV-2 infection after the administration of different vaccine brands as well as the factors influencing the humoral immune response have been analyzed extensively ever since the vaccination program was launched in late 2020. The aim of this study was to determine anti-SARS-CoV-2S antibody titers in 100 healthcare workers 10 months after the administration of two BNT162b2 vaccine doses, and to investigate the influence of demographic characteristics, the presence of comorbidities and history of COVID-19 infection. The results were compared with antibody levels that were determined eight months after the administration of two BNT162b2 vaccine doses in our previous study. Antibody levels in venous blood serum were measured by the ECLIA method with the use of the Roche Cobas e411 analyzer. In all tested subjects, antibody titers remained high 10 months after vaccination, particularly in recovered COVID-19 patients, and only a minor decrease was observed relative to the values noted two months earlier.

A Third Dose of an Inactivated Vaccine Dramatically Increased the Levels and Decay Times of Anti-SARS-CoV-2 Antibodies, but Disappointingly Declined Again: A Prospective, Longitudinal, Cohort Study at 18 Serial Time Points Over 368 Days

Background

Due to anti-SARS-CoV-2 antibody decay and SARS-CoV-2 variants, vaccine booster doses are a constant concern. It was focused on whether the third dose can quickly evoke and activate immunity and produce a sufficient and durable immune protection.

Objectives

To evaluate the responses and durations of five subsets of anti-SARS-CoV-2 antibodies and their predictive values for protection after the administration of a three-dose inactivated SARS-CoV-2 vaccines regimens.

Methods

A prospective cohort study of five subsets of anti-SARS-CoV-2 antibodies (neutralizing antibody, anti-RBD total antibody, anti-Spike IgG, anti-Spike IgM, and anti-Spike IgA) was carried out to evaluate the efficacies and immune characteristics of a three-dose inactivated SARS-CoV-2 vaccines regimen in 32 volunteers. The dynamic response and immune decay were longitudinally profiled at 18 serial time points over 368 days.

Results

The neutralizing antibody, anti-RBD total antibody, anti-Spike IgG and anti-Spike IgA levels rapidly increased to 773.60 (380.90-1273.00) IU/mL, 639.30 (399.60-878.60) AU/mL, 34.48 (16.83-44.68) S/CO and 0.91 (0.35-1.14) S/CO, respectively, after the administration of the third dose. Compared to the peak value after the second dose, these values were increased by 4.22-fold, 3.71-fold, 1.01-fold and 0.92-fold. On the other hand, the half-lives of the neutralizing antibody, anti-RBD total antibody, and anti-Spike IgG were 56.26 (95% CI, 46.81 to 70.49) days, 66.37 (95% CI, 54.90 to 83.88) days, and 82.91 (95% CI, 63.65 to 118.89) days, respectively. Compared to the half-lives after the second dose, these values were increased by 1.71-fold, 2.00-fold, and 2.93-fold, respectively. Nevertheless, the positive conversion rate of anti-Spike IgM was decreased to 9.38% (3/32), which was much lower than that after the second dose (65.63% (21/32)).

Conclusions

Compared to the second dose, the third dose dramatically increased the antibody levels and decay times. However, the half-life of neutralizing antibody remained unsatisfactory. Due to decay, a fourth dose, and even annual revaccination, might be considered in the SARS-CoV-2 vaccination management strategy.

Headache onset after vaccination against SARS-CoV-2: a systematic literature review and meta-analysis

Background

Vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are used to reduce the risk of developing Coronavirus Disease 2019 (COVID-19). Despite the significant benefits in terms of reduced risk of hospitalization and death, different adverse events may present after vaccination: among them, headache is one of the most common, but nowadays there is no summary presentation of its incidence and no description of its main features.

Methods

We searched PubMed and EMBASE covering the period between January 1^st 2020 and August 6^th, 2021, looking for record in English and with an abstract and using three main search terms (with specific variations): COVID-19/SARS-CoV-2; Vaccination; headache/adverse events. We selected manuscript including information on subjects developing headache after injection, and such information had to be derived from a structured form (i.e. no free reporting). Pooled estimates and 95% confidence intervals were calculated. Analyses were carried out by vaccine vs. placebo, by first vs. second dose, and by mRNA-based vs. “traditional” vaccines; finally, we addressed the impact of age and gender on post-vaccine headache onset.

Results

Out of 9338 records, 84 papers were included in the review, accounting for 1.57 million participants, 94% of whom received BNT162b2 or ChAdOx1. Headache was generally the third most common AE: it was detected in 22% (95% CI 18–27%) of subjects after the first dose of vaccine and in 29% (95% CI 23–35%) after the second, with an extreme heterogeneity. Those receiving placebo reported headache in 10–12% of cases. No differences were detected across different vaccines or by mRNA-based vs. “traditional” ones. None of the studies reported information on headache features. A lower prevalence of headache after the first injection of BNT162b2 among older participants was shown.

Conclusions

Our results show that vaccines are associated to a two-fold risk of developing headache within 7 days from injection, and the lack of difference between vaccine types enable to hypothesize that headache is secondary to systemic immunological reaction than to a vaccine-type specific reaction. Some descriptions report onset within the first 24 h and that in around one-third of the cases, headache has migraine-like features with pulsating quality, phono and photophobia; in 40–60% of the cases aggravation with activity is observed. The majority of patients used some medication to treat headache, the one perceived as the most effective being acetylsalicylic acid.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-022-01400-4.

Fever after Vaccination against SARS-CoV-2 with mRNA-Based Vaccine Associated with Higher Antibody Levels during 6 Months Follow-Up

Background: The effect of post-vaccination adverse events on immunogenicity is unknown. We aimed to explore relationship between post-vaccination adverse reactions and antibody levels during 6-month follow-up. Methods: Blood was serially drawn from healthcare workers after the second dose of BNT162b2 mRNA vaccine (Day 12, 30, 60, 90, 120, 150, and 180) and anti-SARS-CoV-2 spike IgG (S-IgG) levels were measured. Following each vaccine dose, volunteers completed a questionnaire regarding adverse reactions (symptomatic vs. asymptomatic groups). Results: A total of 395 subjects received the second dose of the vaccine. The main results were as follows: (i) fever after the 2nd dose was independently associated with the median S-IgG level at all follow-up time points; (ii) significantly higher S-IgG levels were observed in the symptomatic group of patients without prior COVID-19 infection throughout the entire follow-up period; (iii) prior COVID-19 positivity resulted in higher S-IgG levels only in the asymptomatic group from Day 90 of the follow-up period; (iv) both prior COVID-19 disease with asymptomatic status and symptomatic status without prior COVID-19 infection resulted in similar S-IgG antibody levels; (v) significantly lower serum S-IgG levels were observed in smokers. Conclusion: Fever may play an important role in the post-vaccination immune response in the long term.

Risk factors associated with short-term adverse events after SARS-CoV-2 vaccination in patients with immune-mediated inflammatory diseases

BACKGROUND

Studies have suggested incremental short-term adverse events (AE) after repeated vaccination. In this report, we assessed occurrence and risk factors for short-term AEs following repeated SARS-CoV-2 vaccination in patients with various immune-mediated inflammatory diseases (IMIDs).

METHODS

Self-reported daily questionnaires on AEs during the first 7 days after vaccination were obtained of 2259 individuals (2081 patients and 178 controls) participating in an ongoing prospective multicenter cohort study on SARS-CoV-2 vaccination in patients with various IMIDs in the Netherlands (T2B-COVID). Relative risks were calculated for potential risk factors associated with clinically relevant AE (rAE), defined as AE lasting longer than 2 days or impacting daily life.

RESULTS

In total, 5454 vaccinations were recorded (1737 first, 1992 second and 1478 third vaccinations). Multiple sclerosis, Crohn's disease and rheumatoid arthritis were the largest disease groups. rAEs were reported by 57.3% (95% CI 54.8-59.8) of patients after the first vaccination, 61.5% (95% CI 59.2-63.7) after the second vaccination and 58% (95% CI 55.3-60.6) after the third vaccination. At day 7 after the first, second and third vaccination, respectively, 7.6% (95% CI 6.3-9.1), 7.4% (95% CI 6.2-8.7) and 6.8% (95% CI 5.4-8.3) of patients still reported AEs impacting daily life. Hospital admissions and allergic reactions were uncommon (<0.7%). Female sex (aRR 1.43, 95% CI 1.32-1.56), age below 50 (aRR 1.14, 95% CI 1.06-1.23), a preceding SARS-CoV-2 infection (aRR 1.14, 95% CI 1.01-1.29) and having an IMID (aRR 1.16, 95% CI 1.01-1.34) were associated with increased risk of rAEs following a vaccination. Compared to the second vaccination, the first vaccination was associated with a lower risk of rAEs (aRR 0.92, 95% CI 0.84-0.99) while a third vaccination was not associated with increased risk on rAEs (aRR 0.93, 95% CI 0.84-1.02). BNT162b2 vaccines were associated with lower risk on rAEs compared to CX-024414 (aRR 0.86, 95% CI 0.80-0.93).

CONCLUSIONS

A third SARS-CoV-2 vaccination was not associated with increased risk of rAEs in IMID patients compared to the second vaccination. Patients with an IMID have a modestly increased risk of rAEs after vaccination when compared to controls. Most AEs are resolved within 7 days; hospital admissions and allergic reactions were uncommon.

TRIAL REGISTRATION

NL74974.018.20 , Trial ID: NL8900. Registered on 9 September 2020.

Metrics from Wearable Devices as Candidate Predictors of Antibody Response following Vaccination against COVID-19: Data from the Second TemPredict Study

There is significant variability in neutralizing antibody responses (which correlate with immune protection) after COVID-19 vaccination, but only limited information is available about predictors of these responses. We investigated whether device-generated summaries of physiological metrics collected by a wearable device correlated with post-vaccination levels of antibodies to the SARS-CoV-2 receptor-binding domain (RBD), the target of neutralizing antibodies generated by existing COVID-19 vaccines. One thousand, one hundred and seventy-nine participants wore an off-the-shelf wearable device (Oura Ring), reported dates of COVID-19 vaccinations, and completed testing for antibodies to the SARS-CoV-2 RBD during the U.S. COVID-19 vaccination rollout. We found that on the night immediately following the second mRNA injection (Moderna-NIAID and Pfizer-BioNTech) increases in dermal temperature deviation and resting heart rate, and decreases in heart rate variability (a measure of sympathetic nervous system activation) and deep sleep were each statistically significantly correlated with greater RBD antibody responses. These associations were stronger in models using metrics adjusted for the pre-vaccination baseline period. Greater temperature deviation emerged as the strongest independent predictor of greater RBD antibody responses in multivariable models. In contrast to data on certain other vaccines, we did not find clear associations between increased sleep surrounding vaccination and antibody responses.

Tolerability of the BNT162b2 COVID-19 Vaccine during Pregnancy among Polish Healthcare Professionals

The tolerance and safety of vaccination in pregnancy should be assessed in local populations based on ethnic differences across countries. Therefore, this study aimed to determine the tolerability of the BNT162b2 mRNA vaccination in pregnancy in a Polish population. An online questionnaire enquiring about the safety and tolerability of the BNT162b2 mRNA vaccine was distributed to pregnant and non-pregnant female healthcare professionals who had voluntarily received one or two doses of the COVID-19 vaccine in Poland. The two groups were compared simultaneously considering the COVID-19 infection status before vaccination. Compared with that noted in the control group, pregnant women in the COVID-19-free group were less likely to have fever (p = 0.002) or gastrointestinal symptoms (p = 0.009) after the second dose. In the COVID-19-exposed group, pregnant women were less likely to experience local skin reactions (p = 0.009), and myalgia (p = 0.003) after the first dose. After the second dose, the only noticeable difference was a lower incidence of myalgia (p = 0.001) in pregnant women. The tolerability of the BNT162b2 mRNA COVID-19 vaccine was similar in both the groups. No severe local, generalised, or pregnancy complications related to mother or foetus were observed. Good tolerability of the BNT162b2 mRNA COVID-19 vaccine in pregnancy in the Polish population may facilitate the decision to vaccinate pregnant women against COVID-19.

SARS-CoV-2 mRNA Vaccine Breakthrough Infections in Fully Vaccinated Healthcare Personnel: A Systematic Review

The number of people vaccinated against COVID-19 increases worldwide every day; however, it is important to study the risk of breakthrough infections in vaccinated individuals at high risk of exposure such as healthcare personnel (HCP). A systematic literature review (SLR) applying the PRISMA declaration and the PECOS format using the following entry terms was used: "Health Personnel OR Healthcare Worker OR Healthcare Provider OR Healthcare Personnel AND breakthrough OR infection after vaccine*". The research was carried out utilizing the following databases: SCOPUS, PubMed, Embase, and Web of Sciences. An overall very low incidence of post-vaccination breakthrough infections was found, ranging from 0.011 to 0.001 (per 100 individuals at risk). Our findings further support the published high effectiveness rates of mRNA vaccines in preventing SARS-CoV-2 infections among fully vaccinated HCP. Additional studies are needed to define the duration of the vaccine-induced protection among HCP.

Response and Duration of Serum Anti-SARS-CoV-2 Antibodies After Inactivated Vaccination Within 160 Days

Background

A vaccine against coronavirus disease 2019 (COVID-19) with highly effective protection is urgently needed. The anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody response and duration after vaccination are crucial predictive indicators.

Objectives

To evaluate the response and duration for 5 subsets of anti-SARS-CoV-2 antibodies after vaccination and their predictive value for protection.

Methods

We determined the response and duration for 5 subsets of anti-SARS-CoV-2 antibodies (neutralizing antibody, anti-RBD total antibody, anti-Spike IgG, anti-Spike IgM, and anti-Spike IgA) in 61 volunteers within 160 days after the CoronaVac vaccine. A logistic regression model was used to determine the predictors of the persistence of neutralizing antibody persistence.

Results

The seropositivity rates of neutralizing antibody, anti-RBD total antibody, anti-Spike IgG, anti-Spike IgM, and anti-Spike IgA were only 4.92%, 27.87%, 21.31%, 3.28% and 0.00%, respectively, at the end of the first dose (28 days). After the second dose, the seropositivity rates reached peaks of 95.08%, 100.00%, 100.00%, 59.02% and 31.15% in two weeks (42 days). Their decay was obvious and the seropositivity rate remained at 19.67%, 54.10%, 50.82%, 3.28% and 0.00% on day 160, respectively. The level of neutralizing antibody reached a peak of 149.40 (101.00-244.60) IU/mL two weeks after the second dose (42 days) and dropped to 14.23 (7.62-30.73) IU/mL at 160 days, with a half-life of 35.61(95% CI, 32.68 to 39.12) days. Younger participants (≤31 years) had 6.179 times more persistent neutralizing antibodies than older participants (>31 years) (P<0.05). Participants with anti-Spike IgA seropositivity had 4.314 times greater persistence of neutralizing antibodies than participants without anti-Spike IgA seroconversion (P<0.05).

Conclusions

Antibody response for the CoronaVac vaccine was intense and comprehensive with 95.08% neutralizing seropositivity rate, while decay was also obvious after 160 days. Therefore, booster doses should be considered in the vaccine strategies.

Neutralization Assessments Reveal High Cardiothoracic Ratio and Old Age as Independent Predictors of Low Neutralizing Antibody Titers in Hemodialysis Patients Receiving a Single Dose of COVID-19 Vaccine

Background: Data are lacking regarding predictors of quantification of neutralizing antibodies (nAbs) based on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) 50% neutralization titer (NT₅₀) after a single dose of COVID-19 vaccine in hemodialysis (HD) patients. Methods: This prospective single-center study enrolled 200 HD patients and 82 healthy subjects to estimate antibodies against the SARS-CoV-2 viral spike protein 1 and receptor-binding domain after a first dose of a COVID-19 vaccine (ChAdOx1 or mRNA-1273), measured by enzyme-linked immunosorbent assay and applied spline-based generalized additive model regression analysis to predict NT₅₀ converted to international units. Results: After the first dose of ChAdOx1, multiple linear regression showed that age (p = 0.011) and cardiothoracic ratio (p = 0.002) were negatively associated with NT₅₀. Older age (OR = 0.958, p = 0.052) and higher cardiothoracic ratio (OR < 0.001, p = 0.037) could predict negative humoral response (NT₅₀ < 35.13 IU/mL). NT₅₀ was lower in HD patients compared with healthy controls receiving ChAdOx1 (10.68 vs. 43.01 IU/m, p < 0.001) or mRNA-1273 (36.39 vs. 262.2 IU/mL, p < 0.001). ChAdOx1 elicited lower GMTs than mRNA-1273 in the HD cohort (10.68 vs. 36.39 IU/mL, p < 0.001) and in healthy controls (43.01 vs. 262.22 IU/mL, p < 0.001). Conclusion: High cardiothoracic ratio and old age could independently predict a decline in nAb titers in an HD cohort vaccinated with a single dose of ChAdOx1.

Assessment of Post-Vaccination Antibody Response Eight Months after the Administration of BNT1622b2 Vaccine to Healthcare Workers with Particular Emphasis on the Impact of Previous COVID-19 Infection

At the end of 2020, COVID-19 vaccination programs were initiated in many countries, including Poland. The first vaccine approved in Poland was the BNT162b2 mRNA preparation (Pfizer/BioNTech), and the first vaccinated group were healthcare workers. The aim of the present study was to evaluate post-vaccine antibody titers 8 months after the second vaccine dose had been administered to a group of employees of the Hospital of the Ministry of the Interior and Administration in Olsztyn (Poland). The employees were divided into two groups: persons who had COVID-19 in the fourth quarter of 2020 and were vaccinated in January-February 2021, and persons without a history of COVID-19 who were vaccinated during the same period. The analyzed material was venous blood serum collected from 100 hospital employees on 23-28 September 2021. The level of anti-SARS-CoV-2 S antibodies was measured with a Roche Cobas e411 analyzer using the electrochemiluminescence (ECLIA) method. The study demonstrated that persons with a history of SARS-CoV-2 infection had significantly higher antibody levels (taking into account gender, age, type of work performed, and severity of post-vaccination symptoms) than employees without a history of COVID-19. The study also revealed that the type of work, age, gender, and the course of SARS-CoV-2 infection can influence the humoral immune response. The presented results may prove helpful in the context of administering additional vaccine doses.

Overview of Neutralizing Antibodies and Their Potential in COVID-19

The antibody response to respiratory syndrome coronavirus 2 (SARS-CoV-2) has been a major focus of COVID-19 research due to its clinical relevance and importance in vaccine and therapeutic development. Neutralizing antibody (NAb) evaluations are useful for the determination of individual or herd immunity against SARS-CoV-2, vaccine efficacy, and humoral protective response longevity, as well as supporting donor selection criteria for convalescent plasma therapy. In the current manuscript, we review the essential concepts of NAbs, examining their concept, mechanisms of action, production, and the techniques used for their detection; as well as presenting an overview of the clinical use of antibodies in COVID-19.

Counting on COVID-19 Vaccine: Insights into the Current Strategies, Progress and Future Challenges

The emergence of a novel coronavirus viz., severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in late 2019 and its subsequent substantial spread produced the coronavirus disease 2019 (COVID-19) pandemic worldwide. Given its unprecedented infectivity and pathogenicity, the COVID-19 pandemic had a devastating impact on human health, and its clinical management has been a great challenge, which has led to the development and speedy trials of several vaccine candidates against SARS-CoV-2 at an exceptional pace. As a result, several COVID-19 vaccines were made commercially available in the first half of 2021. Although several COVID-19 vaccines showed promising results, crucial insights into their epidemiology, protective mechanisms, and the propensities of reinfection are not largely reviewed. In the present report, we provided insights into the prospects of vaccination against COVID-19 and assessed diverse vaccination strategies including DNA, mRNA, protein subunits, vector-based, live attenuated, and inactivated whole/viral particle-based vaccines. Next, we reviewed major aspects of various available vaccines approved by the World Health Organization and by the local administrations to use against COVID-19. Moreover, we comprehensively assessed the success of these approved vaccines and also their untoward effects, including the possibility of reinfection. We also provided an update on the vaccines that are under development and could be promising candidates in the future. Conclusively, we provided insights into the COVID-19 vaccine epidemiology, their potency, and propensity for SARS-CoV-2 reinfection, while a careful review of their current status, strategies, success, and future challenges was also presented.

Effect of BCG Revaccination on Occupationally Exposed Medical Personnel Vaccinated against SARS-CoV-2

The production of specific neutralizing antibodies by individuals is thought to be the best option for reducing the number of patients with severe COVID-19, which is the reason why multiple vaccines are currently being administered worldwide. We aimed to explore the effect of revaccination with BCG, on the response to a subsequent anti-SARS-CoV-2 vaccine, in persons occupationally exposed to COVID-19 patients. Two groups of 30 randomized participants were selected: one group received a BCG revaccination, and the other group received a placebo. Subsequently, both groups were vaccinated against SARS-CoV-2. After each round of vaccination, the serum concentration of Th1/Th2 cytokines was determined. At the end of the protocol, neutralizing antibodies were determined and the HLA-DRB loci were genotyped. The participants from the BCG group and anti-SARS-CoV-2 vaccine group had increased serum cytokine concentrations (i.e., IL-1β, IL-4, IL-6, IL-12p70, IL-13, IL-18, GM-CSF, INF-γ, and TNF-α) and higher neutralizing antibody titers, compared to the group with Placebo–anti-SARS-CoV-2. Twelve HLA-DRB1 alleles were identified in the Placebo–anti-SARS-CoV-2 group, and only nine in the group revaccinated with BCG. The DRB1*04 allele exhibited increased frequency in the Placebo–anti-SARS-CoV-2 group; however, no confounding effects were found with this allele. We conclude that revaccination with BCG synergizes with subsequent vaccination against SARS-CoV-2 in occupationally exposed personnel.

A Local Health Situation Room for COVID-19: Recommendations for Decision-Making From a Higher Education Institution in Mexico

Introduction: The Situation Room is a physical or virtual space where experts systematically analyze information to characterize a health situation, especially during emergencies. Decision-making processes are made toward solving health needs and promoting collaboration among institutions and social sectors. This paper presents the context and circumstances that led the University of Guadalajara (UdeG) to install a local health situation room (HSR) to address the COVID-19 pandemic at this institution based in the state of Jalisco, Mexico, a narrative is also made of its working processes and some of its results.

Methods: The design of this situation room for COVID-19 was based on the methodology established by the Pan American Health Organization (PAHO)/WHO. This local-type situation room was installed on February 12, 2020. The health problem was characterized, and strategic lines, objectives, and goals were established; the first analysis was derived from an action plan deployed at the UdeG. The strategic lines were situational diagnosis, preventive actions, and containment strategies.

Results: The situation room influenced the activities of the UdeG before the epidemic cases started in the state. One of the actions with the greatest impact was developing a mathematical model for predicting COVID-19 cases. Subsequently, new models have been developed according to the epidemiological evolution of the disease, helping manage the epidemic in the state. Another important result was the early closing of face-to-face university activities, reducing contagion risks and the mobility of more than 310,000 students, faculty, and administrative personnel throughout Jalisco.

Conclusions: A consequence of the closure was that the confinement generated by the pandemic was the change to virtual meetings from April 2020 to date; but at the same time, this working format was a strength, since it influenced the decision of the university board to change all the academic activities to virtual format before other educational, economic, and social activities in the state did. By April 2020, the situation room transcended its institutional boundaries and was invited to participate at the Jalisco State's Health Committee. Its recommendations have helped to maintain the state with one of Mexico's lowest COVID-19 incidence and mortality rates.

A review: Antibody-dependent enhancement in COVID-19: The not so friendly side of antibodies

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), represents an unprecedented global public health emergency with economic and social consequences. One of the main concerns in the development of vaccines is the antibody-dependent enhancement phenomenon, better known as ADE. In this review, we provide an overview of SARS-CoV-2 infection as well as the immune response generated by the host. On the bases of this principle, we also describe what is known about the ADE phenomenon in various viral infections and its possible role as a limiting factor in the development of new vaccines and therapeutic strategies.

BNT162b2 mRNA COVID-19 Vaccine Effectiveness in the Prevention of SARS-CoV-2 Infection and Symptomatic Disease in Five-Month Follow-Up: A Retrospective Cohort Study

To combat the COVID-19 pandemic, a mass vaccination campaign was initiated in Italy on 27 December 2020. The vaccine available to immunize Italian healthcare workers (HCWs) was the BNT162b2 mRNA COVID-19 vaccine (Comirnaty). This study evaluated the effectiveness of the vaccine against documented SARS-CoV-2 infection and symptomatic diseases in the medium- to long-term. HCWs at Bari Policlinico University-Hospital (Italy) who completed the vaccination schedule were matched with HCWs who had refused vaccination; the two groups were followed-up for 5 months (January-May 2021). Vaccine effectiveness (VE) against infection was 97.7% (95.4-99.0%) at 14-34 days after the first dose, and 94.8% (87.0-97.8%), 83.0% (65.0-92.0%), and 81.0% (42.0-94.0%) at 14-41, 42-69, and >69 days, respectively, after the second dose. The estimated VE for documented symptomatic disease was 99.2% (96.4-99.8%) at 14-34 days after the first dose and 97.2% (90.3-99.2%), 85.0% (63.0-94.2%), and 88.0% (42.0-97.6%) at 14-41, 42-69, and >69 days, respectively, after the second dose. Efforts to increase vaccination rates should be strengthened, including mandatory vaccination for HCWs and greater incentives to increase vaccine acceptance by the general population.

Neutralizing Antibodies against SARS-CoV-2, Anti-Ad5 Antibodies, and Reactogenicity in Response to Ad5-nCoV (CanSino Biologics) Vaccine in Individuals with and without Prior SARS-CoV-2

This is the first study outside of clinical trials (phase I–III) evaluating the ability of the Ad5-nCoV vaccine to generate neutralizing antibodies and the factors associated with optimal or suboptimal response. In a longitudinal assay, 346 people (117 with prior COVID-19 and 229 without prior COVID-19) vaccinated with Ad5-nCoV were recruited. The percentage of neutralizing antibodies against SARS-CoV-2 (Surrogate Virus Neutralization Test) and antibodies against Ad5 (ADV-Ad5 IgG ELISA) were quantified pre and post-vaccination effects. The Ad5-nCoV vaccine induces higher neutralizing antibodies percentage in individuals with prior COVID-19 than those without prior COVID-19 (median [IQR]: 98% [97–98.1] vs. 72% [54–90], respectively; p < 0.0001). Furthermore, a natural infection (before vaccination) induces more neutralizing antibodies percentage than immunized individuals without prior COVID-19 (p < 0.01). No patient had vaccine-severe adverse effects. The age, antidepressant, and immunosuppressive treatments, reactogenicity, and history of COVID-19 are associated with impaired antibody production. The anti-Ad5 antibodies increased after 21 days of post-vaccination in all groups (p < 0.01). We recommend the application of a booster dose of Ad5-nCoV, especially for those individuals without previous COVID-19 infection. Finally, the induction of anti-Ad5 antibodies after vaccination should be considered if a booster with the same vaccine is planned.