Journal Description
Vaccines
Vaccines
is an international, peer-reviewed, open access journal published monthly online by MDPI. The American Society for Virology (ASV) is affiliated with Vaccines and their members receive a discount on the article processing charges.
- Open Access— free for readers, with article processing charges (APC) paid by authors or their institutions.
- High Visibility: indexed within Scopus, SCIE (Web of Science), PubMed, PMC, Embase, CAPlus / SciFinder, and many other databases.
- Journal Rank: JCR - Q2 (Immunology)
- Rapid Publication: manuscripts are peer-reviewed and a first decision provided to authors approximately 14.6 days after submission; acceptance to publication is undertaken in 3.8 days (median values for papers published in this journal in the first half of 2021).
- Recognition of Reviewers: reviewers who provide timely, thorough peer-review reports receive vouchers entitling them to a discount on the APC of their next publication in any MDPI journal, in appreciation of the work done.
Impact Factor:
4.422 (2020)
;
5-Year Impact Factor:
5.513 (2020)
Latest Articles
A Therapeutic Hepatitis B Virus DNA Vaccine Induces Specific Immune Responses in Mice and Non-Human Primates
Vaccines 2021, 9(9), 969; https://doi.org/10.3390/vaccines9090969 (registering DOI) - 29 Aug 2021
Abstract
Despite the availability of an effective prophylactic vaccine for more than 30 years, nearly 300 million people worldwide are chronically infected with the hepatitis B virus (HBV), leading to 1 death every 30 s mainly from viral hepatitis-related cirrhosis and liver cancer. Chronic
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Despite the availability of an effective prophylactic vaccine for more than 30 years, nearly 300 million people worldwide are chronically infected with the hepatitis B virus (HBV), leading to 1 death every 30 s mainly from viral hepatitis-related cirrhosis and liver cancer. Chronic HBV patients exhibit weak, transient, or dysfunctional CD8+ T-cell responses to HBV, which contrasts with high CD8+ T-cell responses seen for resolvers of acute HBV infection. Therefore, a therapeutic DNA vaccine was designed, expressing both HBV core and polymerase proteins, and was sequence optimized to ensure high protein expression and secretion. Although the vaccine, administered intramuscularly via electroporation, had no effect on plasma viral parameters in a mouse model of persistent HBV infection, it did induce robust HBV-specific immune responses in healthy and adeno-associated hepatitis B virus (AAV-HBV) infected mice as well as in healthy non-human primates.
Full article
(This article belongs to the Section Hepatitis Virus Vaccines)
Open AccessEditorial
Towards a Prophylactic Vaccine for the Prevention of HCMV Infection
Vaccines 2021, 9(9), 968; https://doi.org/10.3390/vaccines9090968 (registering DOI) - 29 Aug 2021
Abstract
Human cytomegalovirus (HCMV) or human herpesvirus 5, is a ubiquitous human herpesvirus, which can cause severe disease in immunocompromised patients (AIDS patients and solid organ transplant or hematopoietic stem cell transplant recipients) [...]
Full article
(This article belongs to the Special Issue Human Cytomegalovirus: Recent Advances, Novel Targets and Vaccines)
Open AccessArticle
Predictors of Willingness to Receive the COVID-19 Vaccine after Emergency Use Authorization: The Role of Coping Appraisal
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, , , , , , , , , and
Vaccines 2021, 9(9), 967; https://doi.org/10.3390/vaccines9090967 (registering DOI) - 29 Aug 2021
Abstract
The current study aims to identify psychosocial factors based on protection motivation theory (PMT) influencing Chinese adults’ willingness to receive the COVID-19 vaccine after the emergency use authorization of the New Coronavirus Inactivated Vaccine in China. A cross-sectional online survey was conducted among
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The current study aims to identify psychosocial factors based on protection motivation theory (PMT) influencing Chinese adults’ willingness to receive the COVID-19 vaccine after the emergency use authorization of the New Coronavirus Inactivated Vaccine in China. A cross-sectional online survey was conducted among Chinese residents aged 18–59 years, and 2528 respondents from 31 provinces and autonomous regions were included in the current study. Based on PMT, threat appraisals and coping appraisals were measured. Hierarchical multiple regressions and multivariate logistic regressions were used to identify the relationships between the PMT constructs and vaccination willingness after other covariates were controlled for. A total of 1411 (55.8%) respondents reported being willing to receive the COVID-19 vaccine. The PMT model explained 26.6% (p < 0.001) of the variance in the vaccine willingness. The coping appraisals, including response efficacy, self-efficacy, and response costs, were significantly correlated with the willingness to receive the COVID-19 vaccine, and response efficacy was the strongest influencing factor (adjusted OR = 2.93, 95% CI: 2.42–3.54). In conclusion, the coping appraisals for vaccination, instead of threat appraisals regarding the pandemic itself, mainly influenced people’s willingness to get vaccinated after the emergency use authorization of the COVID-19 vaccine in China. These findings are helpful for developing education and interventions to promote vaccination willingness and enhance public health outcomes during a pandemic.
Full article
Open AccessCommunication
Compulsory Vaccination for Healthcare Workers in Italy for the Prevention of SARS-CoV-2 Infection
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, , , , and
Vaccines 2021, 9(9), 966; https://doi.org/10.3390/vaccines9090966 (registering DOI) - 29 Aug 2021
Abstract
The European Convention on Human Rights (ECHR) judgement no. 116(2021) of 8 April 2021 establishes the principle of mandatory vaccination, indicating the criteria that national legislation must comply with, following the principle of non-interference in the private life of the individual. Vaccination for
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The European Convention on Human Rights (ECHR) judgement no. 116(2021) of 8 April 2021 establishes the principle of mandatory vaccination, indicating the criteria that national legislation must comply with, following the principle of non-interference in the private life of the individual. Vaccination for the prevention of SARS-CoV-2 infection appears to be an essential requirement for providing healthcare assistance. The European experience with compulsory vaccinations, offers a composite panorama, as the strategy of some European countries is to make vaccinations compulsory, including financial penalties for non-compliance. As in other countries, there is a clear need for Italy to impose compulsory vaccination for healthcare workers, in response to a pressing social need to protect individual and public health, and above all as a defense for vulnerable subjects or patients, for whom health workers have a specific position of guarantee and trust. The Italian Republic provided for mandatory vaccinations for health professionals by Decree-Law of 1 April 2021 no. 44, to guarantee public health and adequate safety conditions. As stated by ECHR, the Italian State, despite having initially opted for recommendation as regards to SARS-CoV-2 vaccination, had to adopt the mandatory system to achieve the highest possible degree of vaccination coverage among health professionals to guarantee the safety of treatments and protection of patients’ health. We present the Italian situation on vaccine hesitation in healthcare workers, with updated epidemiological data as well as the doctrinaire, social, and political debate that is raging in Italy and Europe.
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(This article belongs to the Special Issue Safety Concerns, Sources of Liability, Compensation Strategies and the Right to Be Informed: Ethical and Legal Issues of COVID-19 Vaccination)
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Open AccessReview
An Update on mRNA-Based Viral Vaccines
Vaccines 2021, 9(9), 965; https://doi.org/10.3390/vaccines9090965 (registering DOI) - 29 Aug 2021
Abstract
With the success of COVID-19 vaccines, newly created mRNA vaccines against other infectious diseases are beginning to emerge. Here, we review the structural elements required for designing mRNA vaccine constructs for effective in vitro synthetic transcription reactions. The unprecedently speedy development of mRNA
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With the success of COVID-19 vaccines, newly created mRNA vaccines against other infectious diseases are beginning to emerge. Here, we review the structural elements required for designing mRNA vaccine constructs for effective in vitro synthetic transcription reactions. The unprecedently speedy development of mRNA vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was enabled with previous innovations in nucleoside modifications during in vitro transcription and lipid nanoparticle delivery materials of mRNA. Recent updates are briefly described in the status of mRNA vaccines against SARS-CoV-2, influenza virus, and other viral pathogens. Unique features of mRNA vaccine platforms and future perspectives are discussed.
Full article
(This article belongs to the Special Issue Vaccines against Infectious Diseases)
Open AccessArticle
Simultaneous Immunization with Multiple Diverse Immunogens Alters Development of Antigen-Specific Antibody-Mediated Immunity
Vaccines 2021, 9(9), 964; https://doi.org/10.3390/vaccines9090964 (registering DOI) - 28 Aug 2021
Abstract
Vaccination remains one of the most successful medical interventions in history, significantly decreasing morbidity and mortality associated with, or even eradicating, numerous infectious diseases. Although traditional immunization strategies have recently proven insufficient in the face of many highly mutable and emerging pathogens, modern
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Vaccination remains one of the most successful medical interventions in history, significantly decreasing morbidity and mortality associated with, or even eradicating, numerous infectious diseases. Although traditional immunization strategies have recently proven insufficient in the face of many highly mutable and emerging pathogens, modern strategies aim to rationally engineer a single antigen or cocktail of antigens to generate a focused, protective immune response. However, the effect of cocktail vaccination (simultaneous immunization with multiple immunogens) on the antibody response to each individual antigen within the combination, remains largely unstudied. To investigate whether immunization with a cocktail of diverse antigens would result in decreased antibody titer against each unique antigen in the cocktail compared to immunization with each antigen alone, we immunized mice with surface proteins from uropathogenic Escherichia coli, Mycobacterium tuberculosis, and Neisseria meningitides, and monitored the development of antigen-specific IgG antibody responses. We found that antigen-specific endpoint antibody titers were comparable across immunization groups by study conclusion (day 70). Further, we discovered that although cocktail-immunized mice initially elicited more robust antibody responses, the rate of titer development decreases significantly over time compared to single antigen-immunized mice. Investigating the basic properties that govern the development of antigen-specific antibody responses will help inform the design of future combination immunization regimens.
Full article
Open AccessCommunication
Risk Factors for Herpes Zoster in Patients with Chronic Kidney Disease: A Case-Control Study
Vaccines 2021, 9(9), 963; https://doi.org/10.3390/vaccines9090963 (registering DOI) - 28 Aug 2021
Abstract
(1) Background: Chronic kidney disease (CKD) increases the susceptibility to the presence of herpes zoster (HZ). Little is known about the risk factors of HZ in CKD patients; (2) Methods: This is a case-control study. CKD patients diagnosed with HZ between January 2015
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(1) Background: Chronic kidney disease (CKD) increases the susceptibility to the presence of herpes zoster (HZ). Little is known about the risk factors of HZ in CKD patients; (2) Methods: This is a case-control study. CKD patients diagnosed with HZ between January 2015 and June 2021 in a tertiary hospital were identified. One age- and gender- matched control was paired for each case, matched to the date of initial HZ diagnosis. Conditional multiple logistic regression was used to evaluate the risk factors associated with the presence of HZ; (3) Results: Forty-seven HZ patients and controls were identified. In general, about 73.40% (69 out of 94) patients were classified at IV to V stages of CKD. Immunosuppressive agents (p = 0.0012) and dialysis therapy (p = 0.021) were reported more frequently in the HZ cohort. Compared with the control group, the total white cell count and lymphocyte count were significantly lower in the HZ group (p value of 0.032 and 0.003, respectively). The conditional logistics regression model revealed that previous immunosuppressants administration (odds ratio: 10.861, 95% CI: 2.092~56.392, p = 0.005) and dialysis therapy (odds ratio: 3.293, 95% CI: 1.047~10.355, p = 0.041) were independent risk factors of HZ in the CKD population; (4) Conclusions: Dialysis and immunosuppressants therapy were associated with greater risk of HZ disease in CKD patients. Further guideline may highlight the necessity of zoster vaccine for patients with CKD, who undertake associated treatment.
Full article
(This article belongs to the Special Issue Herpesvirus-Specific Immunomonitoring in Patient Groups of Increased Risk)
Open AccessArticle
Effectiveness of a Multifaceted Informational-Based and Text Message Reminders on Pneumococcal and Influenza Vaccinations in Hospital Emergency Departments: A Cluster-Randomized Controlled Trial
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, , , , , , , , , , , , , , , , , , and
Vaccines 2021, 9(9), 962; https://doi.org/10.3390/vaccines9090962 (registering DOI) - 28 Aug 2021
Abstract
Objectives. We aimed to evaluate the effectiveness of a multifaceted procedure in improving pneumococcal and influenza vaccinations 6 months after an emergency department (ED) visit among patients aged 65 years and older. Methods. We conducted a cluster-randomized, controlled, parallel-group, open-label implementation trial in
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Objectives. We aimed to evaluate the effectiveness of a multifaceted procedure in improving pneumococcal and influenza vaccinations 6 months after an emergency department (ED) visit among patients aged 65 years and older. Methods. We conducted a cluster-randomized, controlled, parallel-group, open-label implementation trial in 18 EDs in France and Monaco. Participants were recruited from November 2015 to September 2016. EDs were randomly assigned with a 1:1 ratio to provide either a multifaceted procedure that combined structured information about pneumococcal and influenza vaccines and three text message reminders sent to patients every two weeks (intervention arm) or nonstructured information only (control arm). The outcomes were self-reported pneumococcal vaccination and influenza vaccination rates within 6 months of enrollment. Results. A total of 9 EDs were randomized to the intervention arm (n = 780 patients) and 9 to the control arm (n = 695 patients). The median age for all enrolled patients was 74 years (25–75th percentiles, 69 to 82): 50.1% were male, 34.9% had at least one underlying condition, and 30.7% were at risk for invasive pneumococcal infection. In the intention-to-treat analysis, the multifaceted intervention did not alter the pneumococcal vaccination rate (6.4% versus 4.6%, absolute difference: 1.8; 95% CI: [−0.9 to 4.4]; p = 0.19), whereas it improved the influenza vaccination rate (52.1% versus 40.0%, absolute difference: 12.1; 95% CI: [2.4 to 21.8]; p = 0.01). At 12 months, mortality did not differ between the intervention (9.7%) and control (11.2%) arms (p = 0.35). Conclusions. A multifaceted intervention based on text message reminders provides an opportunity to increase anti-influenza vaccination among elderly patients visiting the ED. Efforts are warranted to provide better information on pneumococcal diseases and the benefits of pneumococcal vaccines, especially in the elderly.
Full article
(This article belongs to the Special Issue Vaccines against Pneumococcal Infection)
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Open AccessReview
Bringing Preventive RSV Monoclonal Antibodies to Infants in Low- and Middle-Income Countries: Challenges and Opportunities
Vaccines 2021, 9(9), 961; https://doi.org/10.3390/vaccines9090961 (registering DOI) - 28 Aug 2021
Abstract
Respiratory syncytial virus (RSV) is the leading cause of acute lower respiratory tract infections (LRTIs) in infants. Most deaths occur in infants under 3 months old, and those living in low and middle-income countries (LMICs). There are no maternal or infant RSV vaccines
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Respiratory syncytial virus (RSV) is the leading cause of acute lower respiratory tract infections (LRTIs) in infants. Most deaths occur in infants under 3 months old, and those living in low and middle-income countries (LMICs). There are no maternal or infant RSV vaccines currently approved. An RSV monoclonal antibody (mAb) could fill the gap until vaccines are available. It could also be used when a vaccine is not given, or when there is insufficient time to vaccinate and generate an antibody response. The only currently approved RSV mAb, palivizumab, is too costly and needs monthly administration, which is not possible in LMICs. It is imperative that a safe, effective, and affordable mAb to prevent severe RSV LRTI be developed for infants in LMICs. Next generation, half-life extended mAbs in clinical development, such as nirsevimab, show promise in protecting infants against RSV LRTI. Given that a single dose could cover an entire 5-month season, there is an opportunity to make RSV mAbs affordable for LMICs by investing in improvements in manufacturing efficiency. The challenges of using RSV mAbs in LMICs are the complexities of integrating them into existing healthcare delivery programs and surveillance systems, both of which are needed to define seasonal patterns, and monitor for escape mutants. Collaboration with key stakeholders such as the World Health Organization and Gavi, the Vaccine Alliance, will be essential for achieving this goal.
Full article
(This article belongs to the Special Issue Novel Prophylactic and Therapeutic Strategies against Respiratory Viral Pathogens for Human and Animal Health)
Open AccessArticle
Vaccination against the Protozoan Parasite Histomonas meleagridis Primes the Activation of Toll-Like Receptors in Turkeys and Chickens Determined by a Set of Newly Developed Multiplex RT-qPCRs
Vaccines 2021, 9(9), 960; https://doi.org/10.3390/vaccines9090960 (registering DOI) - 27 Aug 2021
Abstract
Histomonosis in turkeys and chickens is caused by the extracellular parasite Histomonas meleagridis, but the outcome of the disease varies depending on the host species. So far, studies on the immune response against histomonosis focus mainly on different traits of the adaptive immune
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Histomonosis in turkeys and chickens is caused by the extracellular parasite Histomonas meleagridis, but the outcome of the disease varies depending on the host species. So far, studies on the immune response against histomonosis focus mainly on different traits of the adaptive immune system. Activation of toll like receptors (TLR) leads to the interplay between cells of innate and adaptive immunity with consequences on B and T cell clonal expansion. Therefore, the present investigation focused on the interaction of virulent and/or attenuated histomonads with the innate immune system of turkeys and chickens at 4, 10, 21 days post inoculation. The expression of TLRs (TLR1A, 1B, 2A, 2B, 3, 4, 5, 6(Tu), 7, 13(Tu) and 21(Ch)) and pro-inflammatory cytokines (IL1β and IL6) were analysed in caecum and spleen samples by RT-qPCR. Most frequent significant changes in expression levels of TLRs were observed in the caecum following infection with virulent parasites, an effect noticed to a lower degree in tissue samples from birds vaccinated with attenuated parasites. TLR1B, 2B and 4 showed a continuous up-regulation in the caecum of both species during infection or vaccination, followed by challenge with virulent parasites. Vaccinated birds of both species showed a significant earlier change in TLR expression following challenge than birds kept non-vaccinated but challenged. Expression of TLRs and pro-inflammatory cytokines were associated with severe inflammation of diseased birds in the local organ caecum. In the spleen, changes in TLRs and pro-inflammatory cytokines were less prominent and mainly observed in turkey samples. In conclusion, a detailed comparison of TLRs and pro-inflammatory cytokines of the innate immune system following inoculation with attenuated and/or virulent H. meleagridis of two avian host species provides an insight into regulative mechanisms of TLRs in the development of protection and limitation of the disease.
Full article
(This article belongs to the Special Issue Poultry Vaccines)
Open AccessArticle
Enhancement of the HIV-1-Specific Immune Response Induced by an mRNA Vaccine through Boosting with a Poxvirus MVA Vector Expressing the Same Antigen
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Vaccines 2021, 9(9), 959; https://doi.org/10.3390/vaccines9090959 (registering DOI) - 27 Aug 2021
Abstract
Development of a vaccine against HIV remains a major target goal in the field. The recent success of mRNA vaccines against the coronavirus SARS-CoV-2 is pointing out a new era of vaccine designs against pathogens. Here, we have generated two types of mRNA
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Development of a vaccine against HIV remains a major target goal in the field. The recent success of mRNA vaccines against the coronavirus SARS-CoV-2 is pointing out a new era of vaccine designs against pathogens. Here, we have generated two types of mRNA vaccine candidates against HIV-1; one based on unmodified vectors and the other on 1-methyl-3’-pseudouridylyl modified vectors expressing a T cell multiepitopic construct including protective conserved epitopes from HIV-1 Gag, Pol and Nef proteins (referred to as RNA-TMEP and RNA-TMEPmod, respectively) and defined their biological and immunological properties in cultured cells and in mice. In cultured cells, both mRNA vectors expressed the corresponding protein, with higher levels observed in the unmodified mRNA, leading to activated macrophages with differential induction of innate immune molecules. In mice, intranodal administration of the mRNAs induced the activation of specific T cell (CD4 and CD8) responses, and the levels were markedly enhanced after a booster immunization with the poxvirus vector MVA-TMEP expressing the same antigen. This immune activation was maintained even three months later. These findings revealed a potent combined immunization regimen able to enhance the HIV-1-specific immune responses induced by an mRNA vaccine that might be applicable to human vaccination programs with mRNA and MVA vectors.
Full article
(This article belongs to the Special Issue HIV Pathogenesis, Vaccine and Eradication Strategies)
Open AccessReview
Interests of the Non-Human Primate Models for HIV Cure Research
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Vaccines 2021, 9(9), 958; https://doi.org/10.3390/vaccines9090958 (registering DOI) - 27 Aug 2021
Abstract
Non-human primate (NHP) models are important for vaccine development and also contribute to HIV cure research. Although none of the animal models are perfect, NHPs enable the exploration of important questions about tissue viral reservoirs and the development of intervention strategies. In this
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Non-human primate (NHP) models are important for vaccine development and also contribute to HIV cure research. Although none of the animal models are perfect, NHPs enable the exploration of important questions about tissue viral reservoirs and the development of intervention strategies. In this review, we describe recent advances in the use of these models for HIV cure research and highlight the progress that has been made as well as limitations using these models. The main NHP models used are (i) the macaque, in which simian immunodeficiency virus (SIVmac) infection displays similar replication profiles as to HIV in humans, and (ii) the macaque infected by a recombinant virus (SHIV) consisting of SIVmac expressing the HIV envelope gene serving for studies analyzing the impact of anti-HIV Env broadly neutralizing antibodies. Lessons for HIV cure that can be learned from studying the natural host of SIV are also presented here. An overview of the most promising and less well explored HIV cure strategies tested in NHP models will be given.
Full article
(This article belongs to the Special Issue Non-human Primate Research in Immune Modulation and Drug Discovery)
Open AccessArticle
COVID-19 Subunit Vaccine with a Combination of TLR1/2 and TLR3 Agonists Induces Robust and Protective Immunity
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Vaccines 2021, 9(9), 957; https://doi.org/10.3390/vaccines9090957 (registering DOI) - 27 Aug 2021
Abstract
The development of COVID-19 vaccines is critical in controlling global health issues under the COVID-19 pandemic. The subunit vaccines are the safest and most widely used vaccine platform and highly effective against a multitude of infectious diseases. An adjuvant is essential for subunit
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The development of COVID-19 vaccines is critical in controlling global health issues under the COVID-19 pandemic. The subunit vaccines are the safest and most widely used vaccine platform and highly effective against a multitude of infectious diseases. An adjuvant is essential for subunit vaccines to enhance the magnitude and durability of immune responses. In this study, we determined whether a combination of toll-like receptor (TLR)1/2 and TLR3 agonists (L-pampo) can be a potent adjuvant for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) subunit vaccine. We measured a neutralizing antibody (nAb) and an angiotensin-converting enzyme 2 (ACE2) receptor-blocking antibody against SARS-CoV-2 receptor-binding domain (RBD). We also detected interferon-gamma (IFN-γ) production by using ELISPOT and ELISA assays. By employing a ferret model, we detected nAbs and IFN-γ producing cells and measured viral load in nasal wash after the challenge of SARS-CoV-2. We found that SARS-CoV-2 antigens with L-pampo stimulated robust humoral and cellular immune responses. The efficacy of L-pampo was higher than the other adjuvants. Furthermore, in the ferret model, SARS-CoV-2 antigens with L-pampo elicited nAb response and antigen-specific cellular immune response against SARS-CoV-2, resulting in substantially decreased viral load in their nasal wash. Our study suggests that SARS-CoV-2 antigens formulated with TLR agonists, L-pampo, can be a potent subunit vaccine to promote sufficient protective immunity against SARS-CoV-2.
Full article
(This article belongs to the Collection COVID-19 Vaccines and Vaccination)
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Open AccessBrief Report
Rhabdomyolysis Following Ad26.COV2.S COVID-19 Vaccination
Vaccines 2021, 9(9), 956; https://doi.org/10.3390/vaccines9090956 (registering DOI) - 27 Aug 2021
Abstract
We report the case of a 19-year-old male who complained of myalgia, muscle weakness, and darkened urine two days after receiving his Ad26.COV2.S (Johnson & Johnson, New Brunswick, New Jersey, United States) COVID-19 vaccination. Blood examination revealed an increased creatine kinase (CK) level,
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We report the case of a 19-year-old male who complained of myalgia, muscle weakness, and darkened urine two days after receiving his Ad26.COV2.S (Johnson & Johnson, New Brunswick, New Jersey, United States) COVID-19 vaccination. Blood examination revealed an increased creatine kinase (CK) level, and his urinary dipstick tested positive for blood, indicative of acute rhabdomyolysis. Serum creatinine levels were normal. Rhabdomyolysis due to strenuous physical activity was ruled out and further diagnostics excluded an autoimmune cause. Under repeated treatment with intravenous fluid resuscitation (outpatient treatment), his symptoms resolved and peak CK levels of 44,180 U/L returned to almost normal levels within two weeks. Rhabdomyolysis is a rare, potentially fatal vaccine-induced reaction. Further research is needed to better understand the underlying pathomechanism and to investigate whether subcutaneous injection of vaccines may be able to prevent rhabdomyolysis.
Full article
(This article belongs to the Collection COVID-19 Vaccines and Vaccination)
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Open AccessArticle
Descriptive Observational Study of Tdap Vaccination Adhesion in Pregnant Women in the Florentine Area (Tuscany, Italy) in 2019 and 2020
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Vaccines 2021, 9(9), 955; https://doi.org/10.3390/vaccines9090955 (registering DOI) - 26 Aug 2021
Abstract
Background: Tdap (Tetanus-Diphtheria-acellular Pertussis) vaccination is nowadays a worldwide-recommended practice to immunize pregnant women. The vaccine administration at the third trimester of pregnancy (as recommended by the WHO) would ensure antibody protection to both the mother and the newborn and has contributed
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Background: Tdap (Tetanus-Diphtheria-acellular Pertussis) vaccination is nowadays a worldwide-recommended practice to immunize pregnant women. The vaccine administration at the third trimester of pregnancy (as recommended by the WHO) would ensure antibody protection to both the mother and the newborn and has contributed to the significant drop of pertussis cases in infants. The aim of this observational study was to describe for the first time the socio-demographic characteristics and determinants of Tdap vaccination adhesion of pregnant women in the Florentine area. Methods: Information about parents’ vaccination status, their citizenship, employment type and mothers’ previous pregnancies and/or abortions were collected at the time of birth through the assistance birth certificates (CedAP) both for the years 2019 and 2020. This archive and the regional SISPC (Collective Prevention Healthcare Information System) linked using an anonymous unique personal identifier to retrieve the mother’s vaccination status. Results: We found an overall Tdap vaccination adhesion of 43% in 2019 and 47.3% in 2020. Several socio-demographic parameters would determine an increased vaccination adhesion, including parents’ geographical origin, mothers’ age and educational background, as well as the number of previous deliveries, abortions or voluntary termination of pregnancy. Conclusions: Since not much data are available on this topic in Italy, this study may constitute the baseline information for Tdap vaccination adhesion in pregnant women in the Florentine area (Italy). Thus, future successful vaccination strategies may be designed accordingly.
Full article
(This article belongs to the Special Issue Measure to Improve Vaccination Coverage In at Risk Categories: Pregnant Women, Healthcare Workers and Patients with Chronic Diseases)
Open AccessArticle
Predictors of Willingness to Receive COVID-19 Vaccine: Cross-Sectional Study of Palestinian Dental Students
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Vaccines 2021, 9(9), 954; https://doi.org/10.3390/vaccines9090954 (registering DOI) - 26 Aug 2021
Abstract
The overarching aim of this study was to assess the predictors related to the willingness of Palestinian dental students to receive the COVID-19 vaccine when it becomes available. A cross-sectional study was conducted among a universal sample of dental students in the Palestinian
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The overarching aim of this study was to assess the predictors related to the willingness of Palestinian dental students to receive the COVID-19 vaccine when it becomes available. A cross-sectional study was conducted among a universal sample of dental students in the Palestinian territories. Willingness to get the COVID-19 vaccine was related to the following factors: Demographic characteristics, COVID-19-related experiences, beliefs and knowledge about the vaccine, attitudes toward vaccinations in general, and other factors outlined by the WHO SAGE Vaccination Hesitancy Questionnaire. Four hundred and seventeen students completed the questionnaire (response rate = 41.7%). In general, 57.8% (n = 241) were willing to take the COVID-19 vaccine when it became available to them, 27% (n = 114) were hesitant, and 14.9% (n = 62) were not willing to get vaccinated. The final regression model explained 46% of the variation in the willingness to receive the COVID-19 vaccine as follows: Attitudes towards new vaccines (β = 6.23, p < 0.001), believing in a favorable risk–benefit ratio (β = 5.64, p < 0.001), trust in the pharmaceutical industry (β = 5.92, p = 0.001), believing that natural immunity is better than being vaccinated (β = −4.24, p < 0.001), and having enough information about the vaccine (β = 4.12, p < 0.001). Adequate information about vaccines, their risk–benefit ratios, and natural and acquired immunity are important to build trust and favorable attitudes towards vaccines among future dentists.
Full article
(This article belongs to the Special Issue Human Consciousness and Behavior towards Infectious Diseases and Vaccines 2.0)
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Open AccessFeature PaperArticle
A Novel Recombinant Newcastle Disease Vaccine Improves Post- In Ovo Vaccination Survival with Sustained Protection against Virulent Challenge
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Vaccines 2021, 9(9), 953; https://doi.org/10.3390/vaccines9090953 (registering DOI) - 26 Aug 2021
Abstract
In ovo vaccination has been employed by the poultry industry for over 20 years to control numerous avian diseases. Unfortunately, in ovo live vaccines against Newcastle disease have significant limitations, including high embryo mortality and the inability to induce full protection during the
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In ovo vaccination has been employed by the poultry industry for over 20 years to control numerous avian diseases. Unfortunately, in ovo live vaccines against Newcastle disease have significant limitations, including high embryo mortality and the inability to induce full protection during the first two weeks of life. In this study, a recombinant live attenuated Newcastle disease virus vaccine containing the antisense sequence of chicken interleukin 4 (IL-4), rZJ1*L-IL4R, was used. The rZJ1*L-IL4R vaccine was administered in ovo to naïve specific pathogen free embryonated chicken eggs (ECEs) and evaluated against a homologous challenge. Controls included a live attenuated recombinant genotype VII vaccine based on the virus ZJ1 (rZJ1*L) backbone, the LaSota vaccine and diluent alone. In the first of two experiments, ECEs were vaccinated at 18 days of embryonation (DOE) with either 104.5 or 103.5 50% embryo infectious dose (EID50/egg) and chickens were challenged at 21 days post-hatch (DPH). In the second experiment, 103.5 EID50/egg of each vaccine was administered at 19 DOE, and chickens were challenged at 14 DPH. Chickens vaccinated with 103.5 EID50/egg of rZJ1*L-IL4R had hatch rates comparable to the group that received diluent alone, whereas other groups had significantly lower hatch rates. All vaccinated chickens survived challenge without displaying clinical disease, had protective hemagglutination inhibition titers, and shed comparable levels of challenge virus. The recombinant rZJ1*L-IL4R vaccine yielded lower post-vaccination mortality rates compared with the other in ovo NDV live vaccine candidates as well as provided strong protection post-challenge.
Full article
(This article belongs to the Special Issue Vaccine Research against Significant Viral Diseases of Poultry)
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Open AccessArticle
COVID-19 Vaccine Intention among Rural Residents in Mexico: Validation of a Questionnaire
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, , , , , , , , and
Vaccines 2021, 9(9), 952; https://doi.org/10.3390/vaccines9090952 (registering DOI) - 26 Aug 2021
Abstract
The COVID-19 pandemic forced the scientific community and the pharmaceutical industry to develop new vaccines, in an attempt to reach herd immunity and stop the SARS-CoV-2 from spreading. However, to ensure vaccination among the general population, COVID-19 vaccine intention must be measured. So
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The COVID-19 pandemic forced the scientific community and the pharmaceutical industry to develop new vaccines, in an attempt to reach herd immunity and stop the SARS-CoV-2 from spreading. However, to ensure vaccination among the general population, COVID-19 vaccine intention must be measured. So far, no studies have focused on rural residents in Latin America, which represent approximately 20% of the population of this geographical region. In this study, we present the validation of a self-developed questionnaire, which was validated in a pilot study with 40 Spanish-speaking Mexican rural residents in the state of Guerrero, Mexico. In this study, we describe the chronological validation of the questionnaire, including the assessment of its internal consistency and temporal reliability, which we measured with the Cronbach’s alpha and Spearman’s rank correlation coefficient, respectively. After the psychometrical analysis, we were able to validate a 20-item questionnaire, which intends to assess vaccine intention among the rural population. Aiming to develop a comprehensive policy and vaccination strategies, we hope this instrument provides valuable insight regarding COVID-19 vaccination willingness across rural communities in Mexico and Latin America. Finally, if we want to reach worldwide herd immunity, it is important to understand rural residents’ position towards COVID-19 vaccination.
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(This article belongs to the Special Issue Vaccination and Public Health Version II: COVID-19 Vaccination)
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Open AccessCommunication
Willingness to Get the COVID-19 Vaccine among Residents of Slum Settlements
by
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Vaccines 2021, 9(9), 951; https://doi.org/10.3390/vaccines9090951 (registering DOI) - 26 Aug 2021
Abstract
Slum residents are more vulnerable to COVID-19 infection. Without a specific treatment, vaccination became the main strategy against COVID-19. In this study, we determined the rate and factors associated with the willingness to get vaccinated against COVID-19 among slum residents and their main
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Slum residents are more vulnerable to COVID-19 infection. Without a specific treatment, vaccination became the main strategy against COVID-19. In this study, we determined the rate and factors associated with the willingness to get vaccinated against COVID-19 among slum residents and their main reasons associated with the vaccine intention. The study was conducted in Pau da Lima, a slum community in Salvador Brazil. In total, 985 residents were interviewed. Among them 66.0% (650/985) were willing to get vaccinated, 26.1% (257/985) were hesitant to take the vaccine and 7.9% (78/285) were not sure. The main reasons cited for vaccine hesitancy or being unsure were concerns about vaccine efficacy and potential side effects. In contrast, the main reasons cited for wanting the vaccine were the high incidence of COVID-19 cases and participants’ self-perception of their own health history. Multivariate analysis identified that COVID-19 vaccine hesitancy was associated with younger age and low social capital, summarized as low perceived importance of vaccination to protect one’s family, friends and community. Slum residents have been less willing to vaccinate than the general population. Social capital presents a critical opportunity in the design of communication campaigns to increase COVID-19 vaccine acceptance in slum settings.
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(This article belongs to the Special Issue COVID-19 Vaccine Acceptance and Uptake: Insights from Behavioural and Social Sciences)
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Open AccessArticle
Qualitative Assessment of Early Adverse Effects of Pfizer–BioNTech and Sinopharm COVID-19 Vaccines by Telephone Interviews
by
, , , , , , , , , , , , , , , and
Vaccines 2021, 9(9), 950; https://doi.org/10.3390/vaccines9090950 (registering DOI) - 26 Aug 2021
Abstract
Vaccines are considered the best approach for countering the COVID-19 pandemic. In this study, we compared early side effects associated with vaccination with the Sinopharm and Pfizer–BioNTech COVID-19 vaccines. Participants of this observational cohort were interviewed based on semi-structured telephone interviews, with enquiries
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Vaccines are considered the best approach for countering the COVID-19 pandemic. In this study, we compared early side effects associated with vaccination with the Sinopharm and Pfizer–BioNTech COVID-19 vaccines. Participants of this observational cohort were interviewed based on semi-structured telephone interviews, with enquiries about side effects that developed after vaccination with each dose of these vaccines. Overall, 1004 participants were enrolled, of which 51.1% received Sinopharm vaccine and 48.9% received the Pfizer–BioNTech vaccine. After the first dose, 46.3% of participants had an adverse reaction, with injection site pain most commonly being reported (33.2%). Participants who received the Pfizer–BioNTech vaccine had significantly higher frequencies of all types of adverse reactions (p < 0.01), with no significant differences in the duration of adverse reactions between the two vaccines. Regarding the second dose, 48.6% of participants had adverse reactions, with injection site pain being most commonly reported (29%). Those who received the Pfizer vaccine reported higher frequencies of all adverse reactions (p < 0.01). However, a longer duration of adverse reactions was seen among Sinopharm vaccine recipients as compared to Pfizer–BioNTech vaccine recipients (p = 0.01). In conclusion, early adverse effects are reported following all types of vaccines but these are more likely to be encountered following the administration of new-generation vaccines. These side effects are mostly mild and treatable.
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(This article belongs to the Section COVID-19 Vaccines and Vaccination)
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