SARS-CoV-2 and Other Vaccines: Immunogenicity Parameters and Protection

A special issue of Viruses (ISSN 1999-4915). This special issue belongs to the section "SARS-CoV-2 and COVID-19".

Deadline for manuscript submissions: closed (31 July 2022) | Viewed by 47355

Special Issue Editor

Special Issue Information

Dear Colleagues,

During the assessment and licensing of novel vaccines, and in the post-licensure follow up, it is critical to have reliable immunogenicity-testing methods that relate well to protection. The need for reliable immunogenicity criteria became apparent in preparation for the potential pandemic threat posed by influenza A H5N1 in 2006, when great intra- and interlaboratory variations were seen for hemagglutinin inhibition and microneutralization tests, and the need for a centralized standard was acknowledged by the WHO and NIBSC.

In the case of SARS-CoV-2, this remains a critical issue, as many different antibody tests have been developed urgently, but with unknown correlation to real-world protection. Therefore, collaboration among different laboratories and health authorities is essential to establish standards and to reduce interlaboratory variations, and to establish immunogenicity correlates that can be used for licensing as well as patient care. In this Special Issue, we seek papers discussing the development of reliable immunogenicity tests that correlate with the real-world protection of SARS-CoV-2 and other novel vaccines.

Sub-topics: antibody levels; cellular immunity; correlates of protection; rapid vs laboratory antibody kits; the role of ELISA

Dr. Zoltan Vajo
Guest Editor

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Keywords

  • SARS-CoV-2
  • serology
  • cellular immune response
  • protection
  • vaccines

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Published Papers (15 papers)

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Editorial

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2 pages, 169 KiB  
Editorial
Developing Immunity Testing for SARS-CoV-2 and Other Novel Vaccines—Correlates of Immunogenicity Parameters with Protection
by Zoltan Vajo
Viruses 2022, 14(2), 196; https://doi.org/10.3390/v14020196 - 20 Jan 2022
Viewed by 1601
Abstract
During the assessment and licensing of novel vaccines, as well as post licensure follow up, it is critical to have reliable immunogenicity testing methods that relate well to real life protection [...] Full article

Research

Jump to: Editorial, Other

17 pages, 698 KiB  
Article
COVID-19 Vaccine Hesitancy among Pregnant Women Attending Antenatal Clinics in Pakistan: A Multicentric, Prospective, Survey-Based Study
by Zia Ul Mustafa, Shazma Bashir, Arfah Shahid, Iqra Raees, Muhammad Salman, Hamid A. Merchant, Mamoon A. Aldeyab, Chia Siang Kow and Syed Shahzad Hasan
Viruses 2022, 14(11), 2344; https://doi.org/10.3390/v14112344 - 25 Oct 2022
Cited by 10 | Viewed by 2590
Abstract
This study aimed to assess the vaccination status and factors contributing to vaccine hesitancy among pregnant women in the largest province of Pakistan. A multicentric, prospective, survey-based study using an interviewer-administered tool was conducted among pregnant women attending antenatal clinics between 1 December [...] Read more.
This study aimed to assess the vaccination status and factors contributing to vaccine hesitancy among pregnant women in the largest province of Pakistan. A multicentric, prospective, survey-based study using an interviewer-administered tool was conducted among pregnant women attending antenatal clinics between 1 December 2021 through 30 January 2022 across seven hospitals in Pakistan. The healthcare professionals providing care at the participating hospitals administered the survey. Four hundred and five pregnant women fully consented and completed the study. The majority of the study participants (70.6%, n = 286) were aged between 25 and 34 and had a previous successful pregnancy history. More than half of the study participants (56.0%, n = 227) did not receive COVID-19 vaccination at the time of data collection despite their family members (93.9%, n = 372) had already received at least one dose of COVID-19 vaccine. Among those who received COVID-19 vaccination (n = 173), vaccine efficacy, protection for the foetus, and risk of COVID-19-associated hospitalisation were the main driving factors for vaccine hesitancy. The majority of the unvaccinated women (77.8%, n = 182) had no intention of receiving the vaccine. However, more than two-thirds (85.7%, n = 342) consulted the doctor about COVID-19 vaccines, and most were recommended to receive COVID-19 vaccines by the doctors (80.7%, n = 280). Women were significantly more likely to be vaccinated if they had employment (odds ratio [OR] 4.47, 95% confidence interval [CI]: 2.31–8.64) compared with their counterparts who were homemakers, consulted their doctors (OR 0.12, 95% CI: 0.04–0.35), and if they did not have pregnancy-related issues (OR 6.02, 95% CI: 2.36–15.33). In this study, vaccine hesitancy was prevalent, and vaccine uptake was low among pregnant women. Education and employment did impact COVID vaccination uptake, emphasising the need for more targeted efforts to enhance the trust in vaccines. Full article
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15 pages, 1927 KiB  
Article
Protective Immunity of COVID-19 Vaccination with ChAdOx1 nCoV-19 Following Previous SARS-CoV-2 Infection: A Humoral and Cellular Investigation
by Tamiris Azamor, Ingrid Siciliano Horbach, Danielle Brito e Cunha, Juliana Gil Melgaço, Andréa Marques Vieira da Silva, Luciana Neves Tubarão, Adriana de Souza Azevedo, Renata Tourinho Santos, Nathalia dos Santos Alves, Thiago Lazari Machado, Jane Silva, Alessandro Fonseca de Souza, Camilla Bayma, Vanessa Pimenta Rocha, Ana Beatriz Teixeira Frederico, Brenda de Moura Dias, Bruno Pimenta Setatino, Caio Bidueira Denani, Samir Pereira da Costa Campos, Waleska Dias Schwarcz, Michel Vergne Sucupira, Edinea Pastro Mendes, Edimilson Domingos da Silva, Sheila Maria Barbosa de Lima, Ana Paula Dinis Ano Bom and Sotiris Missailidisadd Show full author list remove Hide full author list
Viruses 2022, 14(9), 1916; https://doi.org/10.3390/v14091916 - 30 Aug 2022
Cited by 12 | Viewed by 2731
Abstract
Infections caused by SARS-CoV-2 induce a severe acute respiratory syndrome called COVID-19 and have led to more than six million deaths worldwide. Vaccination is the most effective preventative measure, and cellular and humoral immunity is crucial to developing individual protection. Here, we aim [...] Read more.
Infections caused by SARS-CoV-2 induce a severe acute respiratory syndrome called COVID-19 and have led to more than six million deaths worldwide. Vaccination is the most effective preventative measure, and cellular and humoral immunity is crucial to developing individual protection. Here, we aim to investigate hybrid immunity against SARS-CoV-2 triggered by the ChAadOx1 nCoV-19 vaccine in a Brazilian cohort. We investigated the immune response from ChAadOx1 nCoV-19 vaccination in naïve (noCOVID-19) and previously infected individuals (COVID-19) by analyzing levels of D-dimers, total IgG, neutralizing antibodies (Nabs), IFN-γ (interferon-γ) secretion, and immunophenotyping of memory lymphocytes. No significant differences in D-dimer levels were observed 7 or 15 days after vaccination (DAV). All vaccinated individuals presented higher levels of total IgG or Nabs with a positive correlation (R = 0.88). Individuals in the COVID-19 group showed higher levels of antibody and memory B cells, with a faster antibody response starting at 7 DAV compared to noCOVID-19 at 15 DAV. Further, ChAadOx1 nCoV-19 vaccination led to enhanced IFN-γ production (15 DAV) and an increase in activated T CD4+ naïve cells in noCOVID-19 individuals in contrast with COVID-19 individuals. Hence, our data support that hybrid immunity triggered by ChAadOx1 nCoV-19 vaccination is associated with enhanced humoral response, together with a balanced cellular response. Full article
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23 pages, 3180 KiB  
Article
A Systematic Review and Meta-Analysis of Serologic Response following Coronavirus Disease 2019 (COVID-19) Vaccination in Solid Organ Transplant Recipients
by Atsushi Sakuraba, Alexander Luna and Dejan Micic
Viruses 2022, 14(8), 1822; https://doi.org/10.3390/v14081822 - 19 Aug 2022
Cited by 31 | Viewed by 3486
Abstract
Solid organ transplant (SOT) recipients are at greater risk of coronavirus disease 2019 (COVID-19) and have attenuated response to vaccinations. In the present meta-analysis, we aimed to evaluate the serologic response to the COVID-19 vaccine in SOT recipients. A search of electronic databases [...] Read more.
Solid organ transplant (SOT) recipients are at greater risk of coronavirus disease 2019 (COVID-19) and have attenuated response to vaccinations. In the present meta-analysis, we aimed to evaluate the serologic response to the COVID-19 vaccine in SOT recipients. A search of electronic databases was conducted to identify SOT studies that reported the serologic response to COVID-19 vaccination. We analyzed 44 observational studies including 6158 SOT recipients. Most studies were on mRNA vaccination (mRNA-1273 or BNT162b2). After a single and two doses of vaccine, serologic response rates were 8.6% (95% CI 6.8–11.0) and 34.2% (95% CI 30.1–38.7), respectively. Compared to controls, response rates were lower after a single and two doses of vaccine (OR 0.0049 [95% CI 0.0021–0.012] and 0.0057 [95% CI 0.0030–0.011], respectively). A third dose improved the rate to 65.6% (95% CI 60.4–70.2), but in a subset of patients who had not achieved a response after two doses, it remained low at 35.7% (95% CI 21.2–53.3). In summary, only a small proportion of SOT recipients achieved serologic response to the COVID-19 mRNA vaccine, and that even the third dose had an insufficient response. Alternative strategies for prophylaxis in SOT patients need to be developed. Key Contribution: In this meta-analysis that included 6158 solid organ transplant recipients, the serologic response to the COVID-19 vaccine was extremely low after one (8.6%) and two doses (34.2%). The third dose of the vaccine improved the rate only to 66%, and in the subset of patients who had not achieved a response after two doses, it remained low at 36%. The results of our study suggest that a significant proportion of solid organ transplant recipients are unable to achieve a sufficient serologic response after completing not only the two series of vaccination but also the third booster dose. There is an urgent need to develop strategies for prophylaxis including modified vaccine schedules or the use of monoclonal antibodies in this vulnerable patient population. Full article
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10 pages, 921 KiB  
Article
Development and Validation of Indirect Enzyme-Linked Immunosorbent Assays for Detecting Antibodies to SARS-CoV-2 in Cattle, Swine, and Chicken
by Abhinay Gontu, Erika A. Marlin, Santhamani Ramasamy, Sabarinath Neerukonda, Gayatri Anil, Jasmine Morgan, Meysoon Quraishi, Chen Chen, Veda Sheersh Boorla, Ruth H. Nissly, Padmaja Jakka, Shubhada K. Chothe, Abirami Ravichandran, Nishitha Kodali, Saranya Amirthalingam, Lindsey LaBella, Kathleen Kelly, Pazhanivel Natesan, Allen M. Minns, Randall M. Rossi, Jacob R. Werner, Ernest Hovingh, Scott E. Lindner, Deepanker Tewari, Vivek Kapur, Kurt J. Vandegrift, Costas D. Maranas, Meera Surendran Nair and Suresh V. Kuchipudiadd Show full author list remove Hide full author list
Viruses 2022, 14(7), 1358; https://doi.org/10.3390/v14071358 - 22 Jun 2022
Cited by 2 | Viewed by 3831
Abstract
Multiple domestic and wild animal species are susceptible to SARS-CoV-2 infection. Cattle and swine are susceptible to experimental SARS-CoV-2 infection. The unchecked transmission of SARS-CoV-2 in animal hosts could lead to virus adaptation and the emergence of novel variants. In addition, the spillover [...] Read more.
Multiple domestic and wild animal species are susceptible to SARS-CoV-2 infection. Cattle and swine are susceptible to experimental SARS-CoV-2 infection. The unchecked transmission of SARS-CoV-2 in animal hosts could lead to virus adaptation and the emergence of novel variants. In addition, the spillover and subsequent adaptation of SARS-CoV-2 in livestock could significantly impact food security as well as animal and public health. Therefore, it is essential to monitor livestock species for SARS-CoV-2 spillover. We developed and optimized species-specific indirect ELISAs (iELISAs) to detect anti-SARS-CoV-2 antibodies in cattle, swine, and chickens using the spike protein receptor-binding domain (RBD) antigen. Serum samples collected prior to the COVID-19 pandemic were used to determine the cut-off threshold. RBD hyperimmunized sera from cattle (n = 3), swine (n = 6), and chicken (n = 3) were used as the positive controls. The iELISAs were evaluated compared to a live virus neutralization test using cattle (n = 150), swine (n = 150), and chicken (n = 150) serum samples collected during the COVID-19 pandemic. The iELISAs for cattle, swine, and chicken were found to have 100% sensitivity and specificity. These tools facilitate the surveillance that is necessary to quickly identify spillovers into the three most important agricultural species worldwide. Full article
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20 pages, 4590 KiB  
Article
Systemic Neutralizing Antibodies and Local Immune Responses Are Critical for the Control of SARS-CoV-2
by Shaswath S. Chandrasekar, Yashdeep Phanse, Mariah Riel, Rachel E. Hildebrand, Mostafa Hanafy, Jorge E. Osorio, Sherein S. Abdelgayed and Adel M. Talaat
Viruses 2022, 14(6), 1262; https://doi.org/10.3390/v14061262 - 10 Jun 2022
Cited by 1 | Viewed by 2419
Abstract
Antibody measurements are primarily used to evaluate experimental and approved COVID-19 vaccines, which is unilateral considering our immune responses’ complex nature. Previously, we showed that nanoparticle plasmid DNA adjuvant system, QAC, and MVA based vaccines were immunogenic against SARS-CoV-2. Here, we report on [...] Read more.
Antibody measurements are primarily used to evaluate experimental and approved COVID-19 vaccines, which is unilateral considering our immune responses’ complex nature. Previously, we showed that nanoparticle plasmid DNA adjuvant system, QAC, and MVA based vaccines were immunogenic against SARS-CoV-2. Here, we report on the protective efficacy of systemic humoral and mucosal cell-mediated immune responses in transgenic mice models against SARS-CoV-2 following nanoparticle immunization. Parenteral, intramuscular administration of QAC-based plasmid DNA vaccine-encoding SARS-CoV-2 S and N led to the induction of significant serum neutralizing humoral responses, which reduced viral burden in the lungs and prevented viral dissemination to the brain. In contrast, the mucosal, intranasal administration of a heterologous vaccine elicited significant mucosal cell-mediated immune responses in the lungs that limited lung viral replication. The presented results demonstrate that serum neutralizing humoral and local lung T-cell immune responses are critical for the control of SARS-CoV-2 replication. Full article
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14 pages, 2966 KiB  
Article
Characterization of Immune Response Diversity in Rodents Vaccinated with a Vesicular Stomatitis Virus Vectored COVID-19 Vaccine
by Shen Wang, Cheng Zhang, Bo Liang, Weiqi Wang, Na Feng, Yongkun Zhao, Tiecheng Wang, Zhendong Guo, Feihu Yan, Songtao Yang and Xianzhu Xia
Viruses 2022, 14(6), 1127; https://doi.org/10.3390/v14061127 - 24 May 2022
Cited by 11 | Viewed by 2188
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has emerged as the prime challenge facing public health safety since 2019. Correspondingly, coronavirus disease 2019 (COVID-19) vaccines have been developed and administered worldwide, varying in design strategies, delivery routes, immunogenicity and protective efficacy. Here, a [...] Read more.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has emerged as the prime challenge facing public health safety since 2019. Correspondingly, coronavirus disease 2019 (COVID-19) vaccines have been developed and administered worldwide, varying in design strategies, delivery routes, immunogenicity and protective efficacy. Here, a replication-competent vesicular stomatitis virus (VSV) vectored recombinant COVID-19 vaccine was constructed and evaluated in BALB/c mice and Syrian golden hamsters. In BALB/c mice, intramuscular (i.m.) inoculation of recombinant vaccine induced significantly higher humoral immune response than that of the intranasal (i.n.) inoculation group. Analyses of cellular immunity revealed that a Th1-biased cellular immune response was induced in i.n. inoculation group while both Th1 and Th2 T cells were activated in i.m. inoculation group. In golden hamsters, i.n. inoculation of the recombinant vaccine triggered robust humoral immune response and conferred prominent protective efficacy post-SARS-CoV-2 challenge, indicating a better protective immunity in the i.n. inoculation group than that of the i.m. inoculation group. This study provides an effective i.n.-delivered recombinant COVID-19 vaccine candidate and elucidates a route-dependent manner of this vaccine candidate in two most frequently applied small animal models. Moreover, the golden hamster is presented as an economical and convenient small animal model that precisely reflects the immune response and protective efficacy induced by replication-competent COVID-19 vaccine candidates in other SARS-CoV-2 susceptible animals and human beings, especially in the exploration of i.n. immunization. Full article
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15 pages, 2314 KiB  
Article
The E484K Substitution in a SARS-CoV-2 Spike Protein Subunit Vaccine Resulted in Limited Cross-Reactive Neutralizing Antibody Responses in Mice
by Longbo Hu, Yuhua Xu, Liping Wu, Jin Feng, Lu Zhang, Yongjie Tang, Xiang Zhao, Runming Mai, Liyun Chen, Lingling Mei, Yuanzhen Tan, Yingying Du, Yanping Zhen, Wenhan Su and Tao Peng
Viruses 2022, 14(5), 854; https://doi.org/10.3390/v14050854 - 21 Apr 2022
Cited by 11 | Viewed by 2793
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), especially emerging variants, poses an increased threat to global public health. The significant reduction in neutralization activity against the variants such as B.1.351 in the serum of convalescent patients and vaccinated people calls for the design [...] Read more.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), especially emerging variants, poses an increased threat to global public health. The significant reduction in neutralization activity against the variants such as B.1.351 in the serum of convalescent patients and vaccinated people calls for the design of new potent vaccines targeting the emerging variant. However, since most vaccines approved and in clinical trials are based on the sequence of the original SARS-CoV-2 strain, the immunogenicity and protective efficacy of vaccines based on the B.1.351 variant remain largely unknown. In this study, we evaluated the immunogenicity, induced neutralization activity, and protective efficacy of wild-type spike protein nanoparticle (S-2P) and mutant spike protein nanoparticle (S-4M-2P) carrying characteristic mutations of B.1.351 variant in mice. Although there was no significant difference in the induction of spike-specific IgG responses in S-2P- and S-4M-2P-immunized mice, neutralizing antibodies elicited by S-4M-2P exhibited noteworthy, narrower breadth of reactivity with SARS-CoV-2 variants compared with neutralizing antibodies elicited by S-2P. Furthermore, the decrease of induced neutralizing antibody breadth at least partly resulted from the amino acid substitution at position 484. Moreover, S-4M-2P vaccination conferred insufficient protection against live SARS-CoV-2 virus infection, while S-2P vaccination gave definite protection against SARS-CoV-2 challenge in mice. Together, our study provides direct evidence that the E484K substitution in a SARS-CoV-2 subunit protein vaccine limited the cross-reactive neutralizing antibody breadth in mice and, more importantly, draws attention to the unfavorable impact of this mutation in spike protein of SARS-CoV-2 variants on the induction of potent neutralizing antibody responses. Full article
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15 pages, 2481 KiB  
Article
Developing an Effective Peptide-Based Vaccine for COVID-19: Preliminary Studies in Mice Models
by Haiqiang Yang, Jessica Cao, Xiaoyang Lin, Jingwen Yue, Tarek Zieneldien, Janice Kim, Lianchun Wang, Jianmin Fang, Ruo-Pan Huang, Yun Bai, Kevin Sneed and Chuanhai Cao
Viruses 2022, 14(3), 449; https://doi.org/10.3390/v14030449 - 22 Feb 2022
Cited by 11 | Viewed by 3110
Abstract
Coronavirus disease 2019 (COVID-19) has caused massive health and economic disasters worldwide. Although several vaccines have effectively slowed the spread of the virus, their long-term protection and effectiveness against viral variants are still uncertain. To address these potential shortcomings, this study proposes a [...] Read more.
Coronavirus disease 2019 (COVID-19) has caused massive health and economic disasters worldwide. Although several vaccines have effectively slowed the spread of the virus, their long-term protection and effectiveness against viral variants are still uncertain. To address these potential shortcomings, this study proposes a peptide-based vaccine to prevent COVID-19. A total of 15 B cell epitopes of the wild-type severe acute respiratory coronavirus 2 (SARS-CoV-2) spike (S) protein were selected, and their HLA affinities predicted in silico. Peptides were divided into two groups and tested in C57BL/6 mice with either QS21 or Al(OH)3 as the adjuvant. Our results demonstrated that the peptide-based vaccine stimulated high and durable antibody responses in mice, with the T and B cell responses differing based on the type of adjuvant employed. Using epitope mapping, we showed that our peptide-based vaccine produced antibody patterns similar to those in COVID-19 convalescent individuals. Moreover, plasma from vaccinated mice and recovered COVID-19 humans had the same neutralizing activity when tested with a pseudo particle assay. Our data indicate that this adjuvant peptide-based vaccine can generate sustainable and effective B and T cell responses. Thus, we believe that our peptide-based vaccine can be a safe and effective vaccine against COVID-19, particularly because of the flexibility of including new peptides to prevent emerging SARS-CoV-2 variants and avoiding unwanted autoimmune responses. Full article
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12 pages, 277 KiB  
Article
Risk of Vaccine Breakthrough SARS-CoV-2 Infection and Associated Factors in Healthcare Workers of Trieste Teaching Hospitals (North-Eastern Italy)
by Paolo Basso, Corrado Negro, Luca Cegolon and Francesca Larese Filon
Viruses 2022, 14(2), 336; https://doi.org/10.3390/v14020336 - 7 Feb 2022
Cited by 33 | Viewed by 3426
Abstract
Background: Healthcare workers (HCWs) are particularly exposed to biological risk, including SARS-CoV-2 infection. In order to contrast the current pandemic and alleviate the burden of the disease on the healthcare system, a mass vaccination campaign against COVID-19 has been launched worldwide. Aim To [...] Read more.
Background: Healthcare workers (HCWs) are particularly exposed to biological risk, including SARS-CoV-2 infection. In order to contrast the current pandemic and alleviate the burden of the disease on the healthcare system, a mass vaccination campaign against COVID-19 has been launched worldwide. Aim To evaluate the impact of COVID-19 vaccination in HCWs exposed to SARS-CoV-2, to describe the clinical presentation of COVID-19 in infected HCWs, and to investigate clinical and occupational risk factors for breakthrough infection. Design: Retrospective cohort study. Methods: The cohort of HCWs of Trieste Hospitals were followed up from 1 March 2020, to 30 November 2021 (21 months). All HCWs were periodically screened for SARS-CoV-2 infection by real-time PCR (RT–PCR) analysis. Clinical data were obtained through routine medical surveillance records. Risk factors for SARS-CoV-2 infection were investigated by univariable as well as multivariable logistic regression analysis. Results: Among 4394 HCWs routinely screened for SARS-CoV-2 by PCR on nasopharyngeal swab, a total of 800 incident cases were identified during the entire study period (1 March 2020 to 30 November 2021). Five hundred and sixty-four cases occurred before, and 236 after the start of the vaccination campaign against COVID-19, of whom 155 received a complete vaccination scheme before SARS-CoV-2 infection. Breakthrough infection was featured by mild or no symptoms and was significantly associated with the male sex, BMI > 25, and diabetes mellitus. Some categories of HCWs (physicians and nurse aids/auxiliary personnel) were at a higher risk of breakthrough infection. Conclusions: Fully vaccinated HCWs were less likely to acquire symptomatic as well as asymptomatic SARS-CoV-2 infection. Risk factors for SARS-CoV-2 infection after a full COVID-19 vaccination scheme included the male gender, diabetes mellitus, and overweight. HCWs with higher exposure to COVID-19 patients were at higher risk of breakthrough infection. Full article
10 pages, 966 KiB  
Article
Immunogenicity Following Administration of BNT162b2 and Ad26.COV2.S COVID-19 Vaccines in the Pregnant Population during the Third Trimester
by Ioana Mihaela Citu, Cosmin Citu, Florin Gorun, Ioan Sas, Larisa Tomescu, Radu Neamtu, Andrei Motoc, Oana Maria Gorun, Bogdan Burlea, Felix Bratosin and Daniel Malita
Viruses 2022, 14(2), 307; https://doi.org/10.3390/v14020307 - 2 Feb 2022
Cited by 33 | Viewed by 3596
Abstract
Globally, COVID-19 vaccines are currently being used to prevent transmission and to reduce morbidity and death associated with SARS-CoV-2 infection. Current research reveals that vaccines such as BNT162b2 and Ad26.COV2.S are highly immunogenic and have high short-term effectiveness for most of the known [...] Read more.
Globally, COVID-19 vaccines are currently being used to prevent transmission and to reduce morbidity and death associated with SARS-CoV-2 infection. Current research reveals that vaccines such as BNT162b2 and Ad26.COV2.S are highly immunogenic and have high short-term effectiveness for most of the known viral variants. Clinical trials showed satisfying results in the general population, but the reluctance in testing and vaccinating pregnant women left this category with little evidence regarding the safety, efficacy, and immunogenicity following COVID-19 vaccination. With the worldwide incidence of COVID-19 remaining high and the possibility of new transmissible SARS-CoV-2 mutations, data on vaccination effectiveness and antibody dynamics in pregnant patients are critical for determining the need for special care or further booster doses. An observational study was developed to evaluate pregnant women receiving the complete COVID-19 vaccination scheme using the BNT162b2 and Ad26.COV2.S, and determine pregnancy-related outcomes in the mothers and their newborns, as well as determining adverse events after vaccination and immunogenicity of vaccines during four months. There were no abnormal findings in pregnancy and newborn characteristics comparing vaccinated versus unvaccinated pregnant women. COVID-19 seropositive pregnant women had significantly higher spike antibody titers than seronegative patients with similar characteristics, although they were more likely to develop fever and lymphadenopathy following vaccination. The same group of pregnant women showed no statistically significant differences in antibody titers during a 4-month period when compared with case-matched non-pregnant women. The BNT162b2 and Ad26.COV2.S vaccines are safe to administer during the third trimester of pregnancy, while their safety, efficacy, and immunogenicity remain similar to those of the general population. Full article
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9 pages, 446 KiB  
Article
Timeline of SARS-CoV-2 Spread in Italy: Results from an Independent Serological Retesting
by Emanuele Montomoli, Giovanni Apolone, Alessandro Manenti, Mattia Boeri, Paola Suatoni, Federica Sabia, Alfonso Marchianò, Valentina Bollati, Ugo Pastorino and Gabriella Sozzi
Viruses 2022, 14(1), 61; https://doi.org/10.3390/v14010061 - 30 Dec 2021
Cited by 11 | Viewed by 3686
Abstract
The massive emergence of COVID-19 cases in the first phase of pandemic within an extremely short period of time suggest that an undetected earlier circulation of SARS-CoV-2 might have occurred. Given the importance of this evidence, an independent evaluation was recommended by the [...] Read more.
The massive emergence of COVID-19 cases in the first phase of pandemic within an extremely short period of time suggest that an undetected earlier circulation of SARS-CoV-2 might have occurred. Given the importance of this evidence, an independent evaluation was recommended by the World Health Organization (WHO) to test a subset of samples selected on the level of positivity in ELISA assays (positive, low positive, negative) detected in our previous study of prepandemic samples collected in Italy. SARS-CoV-2 antibodies were blindly retested by two independent centers in 29 blood samples collected in the prepandemic period in Italy, 29 samples collected one year before and 11 COVID-19 control samples. The methodologies used included IgG-RBD/IgM-RBD ELISA assays, a qualitative micro-neutralization CPE-based assay, a multiplex IgG protein array, an ELISA IgM kit (Wantai), and a plaque-reduction neutralization test. The results suggest the presence of SARS-CoV-2 antibodies in some samples collected in the prepandemic period, with the oldest samples found to be positive for IgM by both laboratories collected on 10 October 2019 (Lombardy), 11 November 2019 (Lombardy) and 5 February 2020 (Lazio), the latter with neutralizing antibodies. The detection of IgM and/or IgG binding and neutralizing antibodies was strongly dependent on the different serological assays and thresholds employed, and they were not detected in control samples collected one year before. These findings, although gathered in a small and selected set of samples, highlight the importance of harmonizing serological assays for testing the spread of the SARS-CoV-2 virus and may contribute to a better understanding of future virus dynamics. Full article
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16 pages, 5567 KiB  
Article
Protective Immunity against Gamma and Zeta Variants after Inactivated SARS-CoV-2 Virus Immunization
by Marcilio Jorge Fumagalli, Luiza Antunes Castro-Jorge, Thais Fernanda de Campos Fraga-Silva, Patrick Orestes de Azevedo, Carlos Fabiano Capato, Bruna Amanda Cruz Rattis, Natália Satchiko Hojo-Souza, Vitor Gonçalves Floriano, Julia Teixeira de Castro, Simone Gusmão Ramos, Benedito Antônio Lopes da Fonseca, Vânia Luiza Deperon Bonato, Ricardo Tostes Gazzinelli and Luiz Tadeu Moraes Figueiredo
Viruses 2021, 13(12), 2440; https://doi.org/10.3390/v13122440 - 4 Dec 2021
Cited by 6 | Viewed by 4077
Abstract
The persistent circulation of SARS-CoV-2 represents an ongoing global threat due to the emergence of new viral variants that can sometimes evade the immune system of previously exposed or vaccinated individuals. We conducted a follow-up study of adult individuals that had received an [...] Read more.
The persistent circulation of SARS-CoV-2 represents an ongoing global threat due to the emergence of new viral variants that can sometimes evade the immune system of previously exposed or vaccinated individuals. We conducted a follow-up study of adult individuals that had received an inactivated SARS-CoV-2 vaccine, evaluating antibody production and neutralizing activity over a period of 6 months. In addition, we performed mice immunization with inactivated SARS-CoV-2, and evaluated the immune response and pathological outcomes against Gamma and Zeta variant infection. Vaccinated individuals produced high levels of antibodies with robust neutralizing activity, which was significantly reduced against Gamma and Zeta variants. Production of IgG anti-S antibodies and neutralizing activity robustly reduced after 6 months of vaccination. Immunized mice demonstrated cellular response against Gamma and Zeta variants, and after viral infection, reduced viral loads, IL-6 expression, and histopathological outcome in the lungs. TNF levels were unchanged in immunized or not immunized mice after infection with the Gamma variant. Furthermore, serum neutralization activity rapidly increases after infection with the Gamma and Zeta variants. Our data suggest that immunization with inactivated WT SARS-CoV-2 induces a promptly responsive cross-reactive immunity response against the Gamma and Zeta variants, reducing COVID-19 pathological outcomes. Full article
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5 pages, 1229 KiB  
Brief Report
T Cell Response following Anti-COVID-19 BNT162b2 Vaccination Is Maintained against the SARS-CoV-2 Omicron B.1.1.529 Variant of Concern
by Hila Cohen, Shahar Rotem, Uri Elia, Gal Bilinsky, Itzchak Levy, Theodor Chitlaru and Erez Bar-Haim
Viruses 2022, 14(2), 347; https://doi.org/10.3390/v14020347 - 8 Feb 2022
Cited by 15 | Viewed by 3030
Abstract
The progression of the COVID-19 pandemic has led to the emergence of variants of concern (VOC), which may compromise the efficacy of the currently administered vaccines. Antigenic drift can potentially bring about reduced protective T cell immunity and, consequently, more severe disease manifestations. [...] Read more.
The progression of the COVID-19 pandemic has led to the emergence of variants of concern (VOC), which may compromise the efficacy of the currently administered vaccines. Antigenic drift can potentially bring about reduced protective T cell immunity and, consequently, more severe disease manifestations. To assess this possibility, the T cell responses to the wild-type Wuhan-1 SARS-CoV-2 ancestral spike protein and the Omicron B.1.1.529 spike protein were compared. Accordingly, peripheral blood mononuclear cells (PBMC) were collected from eight healthy volunteers 4–5 months following a third vaccination with BNT162b2, and stimulated with overlapping peptide libraries representing the spike of either the ancestral or the Omicron SARS-CoV-2 virus variants. Quantification of the specific T cells was carried out by a fluorescent ELISPOT assay, monitoring cells secreting interferon-gamma (IFNg), interleukin-10 (IL-10) and interleukin-4 (IL-4). For all the examined individuals, comparable levels of reactivity to both forms of spike protein were determined. In addition, a dominant Th1 response was observed, manifested mainly by IFNg-secreting cells and only limited numbers of IL-10- and IL-4-secreting cells. The data demonstrate stable T cell activity in response to the emerging Omicron variant in the tested individuals; therefore, the protective immunity to the variant following BNT162b2 vaccination is not significantly affected. Full article
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8 pages, 874 KiB  
Brief Report
Antibody Responses after SARS-CoV-2 Vaccination in Patients with Liver Diseases
by Athanasios-Dimitrios Bakasis, Kleopatra Bitzogli, Dimitrios Mouziouras, Abraham Pouliakis, Maria Roumpoutsou, Andreas V. Goules and Theodoros Androutsakos
Viruses 2022, 14(2), 207; https://doi.org/10.3390/v14020207 - 21 Jan 2022
Cited by 33 | Viewed by 3166
Abstract
The novel mRNA-based vaccines against SARS-CoV-2 display encouraging safety and efficacy profiles. However, there is a paucity of data regarding their immunogenicity and safety in patients with liver diseases (PWLD), especially in those with cirrhosis. We prospectively assessed anti-SARS-CoV-2 S-spike IgG antibodies and [...] Read more.
The novel mRNA-based vaccines against SARS-CoV-2 display encouraging safety and efficacy profiles. However, there is a paucity of data regarding their immunogenicity and safety in patients with liver diseases (PWLD), especially in those with cirrhosis. We prospectively assessed anti-SARS-CoV-2 S-spike IgG antibodies and neutralizing activity in fully vaccinated PWLD (n = 87) and controls (n = 40). Seroconversion rates were 97.4% (37/38) in cirrhotic PWLD, 87.8% (43/49) in non-cirrhotic PWLD and 100% (40/40) in controls. Adequate neutralizing activity was detected in 92.1% (35/38), 87.8% (43/49) and 100% (40/40) of cirrhotics, non-cirrhotics and controls, respectively. On multivariable analysis, immunosuppressive treatment was negatively correlated with anti-SARS-CoV-2 antibody titers (coefficient (SE): −2.716 (0.634), p < 0.001) and neutralizing activity (coefficient (SE): −24.379 (4.582), p < 0.001), while age was negatively correlated only with neutralizing activity (coefficient (SE): −0.31(0.14), p = 0.028). A total of 52 responder PWLD were reassessed approximately 3 months post-vaccination and no differences were detected in humoral responses between cirrhotic and non-cirrhotic PWLD. No significant side effects were noted post vaccination, while no symptomatic breakthrough infections were reported during a 6-month follow up. Overall, our study shows that m-RNA-based SARS-CoV-2 vaccines are safe and efficacious in PWLD. However, PWLD under immunosuppressive treatment and those of advanced age should probably be more closely monitored after vaccination. Full article
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