Vaccines

19 pages, 4867 KiB

Open AccessArticle

Vaccine Potency and Structure of Yeast-Produced Polio Type 2 Stabilized Virus-like Particles

by Qin Hong, Shuxia Wang, Xiaoli Wang, Wenyu Han, Tian Chen, Yan Liu, Fei Cheng, Song Qin, Shengtao Zhao, Qingwei Liu, Yao Cong and Zhong Huang

Vaccines 2024, 12(9), 1077; https://doi.org/10.3390/vaccines12091077 (registering DOI) - 20 Sep 2024

Abstract

Poliovirus (PV) is on the brink of eradication due to global vaccination programs utilizing live-attenuated oral and inactivated polio vaccines. Recombinant PV virus-like particles (VLPs) are emerging as a safe next-generation vaccine candidate for the impending polio-free era. In this study, we investigate [...] Read more.

Poliovirus (PV) is on the brink of eradication due to global vaccination programs utilizing live-attenuated oral and inactivated polio vaccines. Recombinant PV virus-like particles (VLPs) are emerging as a safe next-generation vaccine candidate for the impending polio-free era. In this study, we investigate the production, antigenicity, thermostability, immunogenicity, and structures of VLPs derived from PV serotype 2 (PV2) wildtype strain and thermally stabilized mutant (wtVLP and sVLP, respectively). Both PV2 wtVLP and sVLP are efficiently produced in Pichia pastoris yeast. The PV2 sVLP displays higher levels of D-antigen and significantly enhanced thermostability than the wtVLP. Unlike the wtVLP, the sVLP elicits neutralizing antibodies in mice at levels comparable to those induced by inactivated polio vaccine. The addition of an aluminum hydroxide adjuvant to sVLP results in faster induction and a higher magnitude of neutralizing antibodies. Furthermore, our cryo-EM structural study of both sVLP and wtVLP reveals a native conformation for the sVLP and a non-native expanded conformation for the wtVLP. Our work not only validates the yeast-produced PV2 sVLP as a promising vaccine candidate with high production potential but also sheds light on the structural mechanisms that underpin the assembly and immunogenicity of the PV2 sVLP. These findings may expedite the development of sVLP-based PV vaccines. Full article

(This article belongs to the Special Issue The 3rd Edition: Development of Vaccines Based on Virus-Like Particles)

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16 pages, 752 KiB

Open AccessArticle

SMS-Based Active Surveillance of Adverse Events following Immunization in Children: The VigiVax Study

by Laura Augusta Gonella, Francesca Moretti, Annalisa Capuano, Caterina De Sarro, Lorenza Ferrara, Elisabetta Geninatti, Greta Guarnieri, Xhikjana Hysolakoj, Margherita Lalli, Olivia Leoni, Antea Maria Pia Mangano, Patrizia Marani Toro, Viviana Mecchia, Maria Caterina Merlano, Caterina Palleria, Anna Maria Potenza, Paola Rossi, Marco Rossi, Francesca Sanità, Ester Sapigni, Cristina Scavone, Claudia Sommaro, Marco Tuccori, Giovanna Zanoni, Ugo Moretti and VigiVax Working Group Show full author list Hide full author list

Vaccines 2024, 12(9), 1076; https://doi.org/10.3390/vaccines12091076 (registering DOI) - 20 Sep 2024

Abstract

Underreporting is the main limitation of spontaneous reporting systems. This cohort-event monitoring study aims to examine the potential of short message service (SMS)-based surveillance compared to traditional surveillance systems. Using VigiVax software, parents of vaccinated children aged two years or younger, in the [...] Read more.

Underreporting is the main limitation of spontaneous reporting systems. This cohort-event monitoring study aims to examine the potential of short message service (SMS)-based surveillance compared to traditional surveillance systems. Using VigiVax software, parents of vaccinated children aged two years or younger, in the period March 2021–May 2022, received a single SMS inquiry about adverse events following immunization (AEFI). Responses were collected, validated by health operators and integrated with the information on electronic immunization registries. AEFI reports were automatically submitted to the Italian Pharmacovigilance system. Among 254,160 SMS messages sent, corresponding to 451,656 administered doses (AD), 71,643 responses were collected (28.2% response rate), and 21,231 of them (8.3%) reported AEFI. After a seriousness assessment based on clinical criteria, 50 reports (0.24%) were classified as serious. Among these, a causality assessment identified 31 reports at least potentially related to the vaccination (RR: 6.86/100,000 AD). Febrile seizures following MMRV (measles, mumps, rubella, varicella) vaccination accounted for 11 of these 31 cases, with an incidence of 32 per 100,000 AD. No fatal outcomes were reported. Our findings support the highly favorable risk profile of pediatric vaccinations and the possibility to improve spontaneous reporting through the integration of digital technologies. Full article

(This article belongs to the Special Issue Impact of Immunization Safety Monitoring on Vaccine Coverage)

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24 pages, 2652 KiB

Open AccessArticle

An Application of an Initial Full Value of Vaccine Assessment Methodology to Measles-Rubella MAPs for Use in Low- and Middle-Income Countries

by Melissa Ko, Collrane Frivold, Mercy Mvundura, Adam Soble, Christopher Gregory, Hans Christiansen, Mateusz Hasso-Agopsowicz, Han Fu, Mark Jit, Shan Hsu, Jessica Joyce Mistilis, Tiziana Scarna, Kristen Earle, Marion Menozzi-Arnaud, Birgitte Giersing, Courtney Jarrahian, Ahmadu Yakubu, Stefano Malvolti and Jean-Pierre Amorij

Vaccines 2024, 12(9), 1075; https://doi.org/10.3390/vaccines12091075 - 19 Sep 2024

Abstract

Measles and rubella micro-array patches (MR-MAPs) are a promising innovation to address limitations of the current needle and syringe (N&S) presentation due to their single-dose presentation, ease of use, and improved thermostability. To direct and accelerate further research and interventions, an initial full [...] Read more.

Measles and rubella micro-array patches (MR-MAPs) are a promising innovation to address limitations of the current needle and syringe (N&S) presentation due to their single-dose presentation, ease of use, and improved thermostability. To direct and accelerate further research and interventions, an initial full value vaccine assessment (iFVVA) was initiated prior to MR-MAPs entering phase I trials to quantify their value and identify key data gaps and challenges. The iFVVA utilized a mixed-methods approach with rapid assessment of literature, stakeholder interviews and surveys, and quantitative data analyses to (i) assess global need for improved MR vaccines and how MR-MAPs could address MR problem statements; (ii) estimate costs and benefits of MR-MAPs; (iii) identify the best pathway from development to delivery; and (iv) identify outstanding areas of need where stakeholder intervention can be helpful. These analyses found that if MR-MAPs are broadly deployed, they can potentially reach an additional 80 million children compared to the N&S presentation between 2030–2040. MR-MAPs can avert up to 37 million measles cases, 400,000 measles deaths, and 26 million disability-adjusted life years (DALYs). MR-MAPs with the most optimal product characteristics of low price, controlled temperature chain (CTC) properties, and small cold chain volumes were shown to be cost saving for routine immunization (RI) in low- and middle-income countries (LMICs) compared to N&S. Uncertainties about price and future vaccine coverage impact the potential cost-effectiveness of introducing MR-MAPs in LMICs, indicating that it could be cost-effective in 16–81% of LMICs. Furthermore, this iFVVA highlighted the importance of upfront donor investment in manufacturing set-up and clinical studies and the critical influence of an appropriate price to ensure country and manufacturer financial sustainability. To ensure that MR-MAPs achieve the greatest public health benefit, MAP developers, vaccine manufacturers, donors, financiers, and policy- and decision-makers will need close collaboration and open communications. Full article

(This article belongs to the Special Issue Estimating Vaccines' Value and Impact)

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16 pages, 2175 KiB

Open AccessArticle

Immune Response after Vaccination against Tick-Borne Encephalitis Virus (TBEV) in Horses

by Dana Kälin, Angela Becsek, Helen Stürmer, Claudia Bachofen, Denise Siegrist, Hulda R. Jonsdottir and Angelika Schoster

Vaccines 2024, 12(9), 1074; https://doi.org/10.3390/vaccines12091074 - 19 Sep 2024

Abstract

(1) Background: Horses infected by a tick-borne encephalitis virus (TBEV) can develop clinically apparent infections. In humans, vaccination is the most effective preventive measure, while a vaccine is not available for horses. The objective of this study was to describe the immune response [...] Read more.

(1) Background: Horses infected by a tick-borne encephalitis virus (TBEV) can develop clinically apparent infections. In humans, vaccination is the most effective preventive measure, while a vaccine is not available for horses. The objective of this study was to describe the immune response in horses after a TBEV vaccination with a human vaccine. (2) Materials and Methods: Seven healthy horses were randomised to a treatment or a control group in a stratified fashion based on TBEV–IgG concentrations on day −4. The treatment group (n = 4) was intramuscularly vaccinated using an inactivated human TBEV vaccine on days 0 and 28; the control group (n = 3) did not receive an injection. A clinical examination and blood sampling were performed on day –4, 0, 2, 4, 6, 8, 10, 14, 28, 30, 32, 34, 36, 38, 43, 56, 84, and 373. A linear mixed model analysis was used to compare IgG and IgM concentrations, neutralising antibody (nAb) titres, leucocyte count, serum amyloid A (SAA), and fibrinogen and globulin concentrations between the groups and time points. (3) Results: The clinical examination was normal in all horses at all time points. There were no significant changes in SAA, globulin, and fibrinogen concentrations and leucocyte count between the groups or time points (all p > 0.05). There was no significant increase in IgG, IgM, or nAb titres in the control group over time (all p > 0.05). In the vaccination group, there was a significant increase in IgG concentration and nAb titres after the second vaccination (p < 0.0001). There was no significant increase in IgM antibodies after the TBEV vaccination (all p > 0.05). One horse in the vaccination group had an IgM concentration above the laboratory reference on day 10. (4) Conclusions: The human TBEV vaccine did not have side effects when used in healthy horses in this study. A significant rise in TBEV-specific IgG antibodies and nAbs after the second vaccination was observed. However, IgG and nAb titres have been shown to decrease within 1 year after vaccination. The results of this study indicate that a vaccination with a human vaccine only induces a mild rise in IgM antibodies and only in previously naive horses. With no significant changes to inflammatory parameters in the vaccinated horses, it remains unclear whether vaccination with the human vaccine leads to protective immunity. Full article

(This article belongs to the Section Veterinary Vaccines)

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13 pages, 547 KiB

Open AccessArticle

Are HPV Vaccines Well Accepted among Parents of Adolescent Girls in China? Trends, Obstacles, and Practical Implications for Further Interventions: A Five-Year Follow-Up Study

by Yu Huang, Jie Ling, Xiang Zhao, Qiaohong Lv, Lei Wang, Qingqing Wu, Shuiyang Xu and Xuehai Zhang

Vaccines 2024, 12(9), 1073; https://doi.org/10.3390/vaccines12091073 - 19 Sep 2024

Abstract

Background: In 2020, the WHO proposed the global strategic goal of accelerating the elimination of cervical cancer (CC). One of the key strategies is that, by 2030, 90% of girls will complete HPV vaccination by age 15. In 2017, HPV vaccines were first [...] Read more.

Background: In 2020, the WHO proposed the global strategic goal of accelerating the elimination of cervical cancer (CC). One of the key strategies is that, by 2030, 90% of girls will complete HPV vaccination by age 15. In 2017, HPV vaccines were first marketed in China. Objectives: This study aimed to explore the changes in parents’ knowledge about CC, HPV, HPV vaccines, and acceptance of HPV vaccination 5 years after the introduction of HPV vaccines into China. Associated factors and reasons for refusal by parents were also explored. Methods: A school-based follow-up study was conducted among parents in China from May 2018 to May 2023. Comparison using Chi-square tests was performed to measure the changes. Univariate and multivariate analyses were used to explore factors associated with HPV vaccination among teenage girls. Results: The overall cognitive level in terms of CC- and HPV-related knowledge among parents increased, and they expressed more willingness to vaccinate their daughter (35.4% in 2018 vs. 56.6% in 2023). The HPV vaccination rate among teenage girls remained at a low level (4.4% in 2018, 9.8% in 2023). The main obstacles reported by parents were limited knowledge (42.0%), scarcity of the HPV vaccine (29.2%), waiting until their daughter was older (27.5%), safety concerns (14.7%), high cost (9.0%), and effectiveness concerns (4.6%). Parents who are elderly, local residents, have received HPV vaccines themselves, have had experience of vaccinating their children with influenza vaccines, and have a higher knowledge level of CC, HPV and HPV vaccines are more likely to vaccinate their children with HPV vaccines. Conclusions: Although we observed an increment in parents’ knowledge level in terms of CC, HPV, HPV vaccines, and HPV vaccine uptake over the past 5 years, the HPV vaccine coverage among girls still falls short of the WHO’s 2030 target. Comprehensive intervention strategies, including tailored health education among adolescents and their parents, doctor recommendations, and providing financial subsidies or free HPV vaccines are needed in China. Full article

(This article belongs to the Special Issue Advancing the Science on Vaccine Hesitancy to Inform Interventions)

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18 pages, 1975 KiB

Open AccessReview

Navigating the Evolving Landscape of COVID-19: Strategies to Increase Vaccine Confidence and Improve Vaccination Rates in the United States

by James A. Mansi, Heather R. Hensler, Rachel Dawson, Reed Tuckson and Todd Wolynn

Vaccines 2024, 12(9), 1072; https://doi.org/10.3390/vaccines12091072 - 19 Sep 2024

Abstract

The COVID-19 pandemic has had a significant impact on every individual in the United States. The launch of the COVID-19 vaccines is estimated to have averted millions of deaths and reduced over 18 million COVID-19-related hospitalizations. In September 2023, the updated 2023–2024 COVID-19 [...] Read more.

The COVID-19 pandemic has had a significant impact on every individual in the United States. The launch of the COVID-19 vaccines is estimated to have averted millions of deaths and reduced over 18 million COVID-19-related hospitalizations. In September 2023, the updated 2023–2024 COVID-19 vaccine, which includes a monovalent component that corresponds to the omicron variant XBB.1.5, reflecting the predominant circulating variant at the time of strain selection, was approved and was recommended for use in all people ≥ 6 months of age. Despite this recommendation, the US uptake of the updated COVID-19 vaccines over the 2023–2024 season has been far from optimal, placing many people at unnecessary risk of severe COVID-19 outcomes. This paper provides an overview of the current state of COVID-19 in 2023–2024 and barriers to vaccine uptake. With the continued evolution of the virus, the potential for more virulent variants, reduced public acceptance of vaccination, and the potential barriers that contributed to low vaccine uptake are explored to provide solutions for improving COVID-19 protection for future seasons. Full article

(This article belongs to the Special Issue Advance Public Health through Vaccination)

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29 pages, 1137 KiB

Open AccessReview

Virulence and Immune Evasion Strategies of FMDV: Implications for Vaccine Design

by Gisselle N. Medina and Fayna Diaz San Segundo

Vaccines 2024, 12(9), 1071; https://doi.org/10.3390/vaccines12091071 - 19 Sep 2024

Abstract

Foot-and-mouth disease (FMD) is globally recognized as a highly economically devastating and prioritized viral disease affecting livestock. Vaccination remains a crucial preventive measure against FMD. The improvement of current vaccine platforms could help control outbreaks, leading to the potential eradication of the disease. [...] Read more.

Foot-and-mouth disease (FMD) is globally recognized as a highly economically devastating and prioritized viral disease affecting livestock. Vaccination remains a crucial preventive measure against FMD. The improvement of current vaccine platforms could help control outbreaks, leading to the potential eradication of the disease. In this review, we describe the variances in virulence and immune responses among FMD-susceptible host species, specifically bovines and pigs, highlighting the details of host–pathogen interactions and their impact on the severity of the disease. This knowledge serves as an important foundation for translating our insights into the rational design of vaccines and countermeasure strategies, including the use of interferon as a biotherapeutic agent. Ultimately, in this review, we aim to bridge the gap between our understanding of FMDV biology and the practical approaches to control and potentially eradicate FMD. Full article

(This article belongs to the Special Issue Interplay between Host and Pathogen: Effects of Infection and Immune Responses)

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12 pages, 1475 KiB

Open AccessArticle

Humoral Immunity and Antibody Responses against Diphtheria, Tetanus, and Pneumococcus after Immune Effector Cell Therapies: A Prospective Study

by Georgios Angelidakis, Roy F. Chemaly, Pranoti V. Sahasrabhojane, Oscar Morado-Aramburo, Ying Jiang, Micah M. Bhatti, Elizabeth Shpall, Chitra Hosing, Preetesh Jain, Kris Michael Mahadeo, Fareed Khawaja, Peter Elhajj, Jennifer A. Wargo, Robert R. Jenq, Nadim J. Ajami, Partow Kebriaei and Ella J. Ariza-Heredia

Vaccines 2024, 12(9), 1070; https://doi.org/10.3390/vaccines12091070 - 19 Sep 2024

Abstract

Patients undergoing immune effector cell therapy (IECT) are at high risk for infections. We assessed seropositivity against pneumococcus, tetanus, and diphtheria in patients before and after IECT and the patients’ response to vaccination. We enrolled patients who underwent IECT from January 2020 to [...] Read more.

Patients undergoing immune effector cell therapy (IECT) are at high risk for infections. We assessed seropositivity against pneumococcus, tetanus, and diphtheria in patients before and after IECT and the patients’ response to vaccination. We enrolled patients who underwent IECT from January 2020 to March 2022. Antibody levels for diphtheria, tetanus, and pneumococcus were measured before IECT, at 1 month, and 3–6 months after. Eligible patients were vaccinated after IECT. In non-seroprotected patients, we discontinued testing. Before IECT, most patients had seroprotective antibody levels against tetanus (68/69, 99%) and diphtheria (65/69, 94%), but fewer did against pneumococcus (24/67, 36%). After IECT, all patients had seroprotective antibody levels for tetanus at 1 month (68/68) and 3–6 months (56/56). For diphtheria, 65/65 patients (100%) had seroprotective antibody levels at 1 month, and 48/53 (91%) did at 3–6 months. For pneumococcus, seroprotective antibody levels were identified in 91% (21/23) of patients at 1 month and 79% (15/19) at 3–6 months following IECT. Fifteen patients received a pneumococcal vaccine after IECT, but none achieved seroprotective response. One patient received the tetanus-diphtheria vaccine and had a seroprotective antibody response. Because some patients experience loss of immunity after IECT, studies evaluating vaccination strategies post-IECT are needed. Full article

(This article belongs to the Special Issue Advances in Vaccines against Infectious Diseases)

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10 pages, 386 KiB

Open AccessArticle

Progress with the Second Dose Measles Vaccine Introduction and Coverage in the WHO African Region

by Balcha G. Masresha, Messeret E. Shibeshi, Gavin B. Grant, Cynthia Hatcher and Charles S. Wiysonge

Vaccines 2024, 12(9), 1069; https://doi.org/10.3390/vaccines12091069 - 18 Sep 2024

Abstract

Introduction: To achieve global and regional measles elimination objectives, the World Health Organization (WHO) recommends coverage of 95% or higher with two doses of measles-containing vaccine. A second dose of measles-containing vaccine (MCV) is typically administered in the second year of life after [...] Read more.

Introduction: To achieve global and regional measles elimination objectives, the World Health Organization (WHO) recommends coverage of 95% or higher with two doses of measles-containing vaccine. A second dose of measles-containing vaccine (MCV) is typically administered in the second year of life after 12 months of age. Methods: We reviewed WHO-UNICEF estimates of national coverage (WUENIC) for the first and second doses of MCV (MCV1 and MCV2, respectively) and calculated drop-out rates between MCV1 and MCV2 for countries in the WHO African Region. Results: From 2013 to 2023, estimated regional MCV2 coverage increased from 7% to 49%, and at the end of 2023, 43 (91%) countries had introduced MCV2 into their routine immunization programs. Countries with more antigens provided in the second year of life had higher mean and median MCV2 coverage levels, and lower drop-out rates between MCV1 and MCV2, as compared to countries providing only MCV2. Discussion: Despite substantial progress, MCV2 coverage remains below the required levels to achieve and sustain elimination, and many countries have high drop-out rates between MCV1 and MCV2 coverage, indicating challenges in reaching children over 12 months of age. Increasing coverage of MCV2 and other vaccines in the second year of life is essential to achieving higher and equitable routine immunization coverage. This will require continued efforts to understand and mitigate barriers to reaching children after 12 months of age and accelerated implementation of available tools. Full article

(This article belongs to the Special Issue A World without Measles and Rubella: Meeting the Regional Elimination Targets on the Path to Global Eradication)

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23 pages, 6419 KiB

Open AccessArticle

Adjuvant Use of the Invariant-Natural-Killer-T-Cell Agonist α-Galactosylceramide Leads to Vaccine-Associated Enhanced Respiratory Disease in Influenza-Vaccinated Pigs

by Bianca L. Artiaga, Daniel Madden, Taeyong Kwon, Chester McDowell, Cassidy Keating, Velmurugan Balaraman, Darling Melany de Carvahlo Madrid, Laurie Touchard, Jamie Henningson, Philip Meade, Florian Krammer, Igor Morozov, Juergen A. Richt and John P. Driver

Vaccines 2024, 12(9), 1068; https://doi.org/10.3390/vaccines12091068 - 18 Sep 2024

Abstract

Invariant natural killer T (iNKT) cells are glycolipid-reactive T cells with potent immunoregulatory properties. iNKT cells activated with the marine-sponge-derived glycolipid, α-galactosylceramide (αGC), provide a universal source of T-cell help that has shown considerable promise for a wide array of therapeutic applications. This [...] Read more.

Invariant natural killer T (iNKT) cells are glycolipid-reactive T cells with potent immunoregulatory properties. iNKT cells activated with the marine-sponge-derived glycolipid, α-galactosylceramide (αGC), provide a universal source of T-cell help that has shown considerable promise for a wide array of therapeutic applications. This includes harnessing iNKT-cell-mediated immune responses to adjuvant whole inactivated influenza virus (WIV) vaccines. An important concern with WIV vaccines is that under certain circumstances, they are capable of triggering vaccine-associated enhanced respiratory disease (VAERD). This immunopathological phenomenon can arise after immunization with an oil-in-water (OIW) adjuvanted WIV vaccine, followed by infection with a hemagglutinin and neuraminidase mismatched challenge virus. This elicits antibodies (Abs) that bind immunodominant epitopes in the HA2 region of the heterologous virus, which purportedly causes enhanced virus fusion activity to the host cell and increased infection. Here, we show that αGC can induce severe VAERD in pigs. However, instead of stimulating high concentrations of HA2 Abs, αGC elicits high concentrations of interferon (IFN)-γ-secreting cells both in the lungs and systemically. Additionally, we found that VAERD mediated by iNKT cells results in distinct cytokine profiles and altered adaptation of the challenge virus following infection compared to an OIW adjuvant. Overall, these results provide a cautionary note about considering the formulation of WIV vaccines with iNKT-cell agonists as a potential strategy to modulate antigen-specific immunity. Full article

(This article belongs to the Special Issue Immunity to Influenza Viruses and Vaccines)

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18 pages, 1729 KiB

Open AccessSystematic Review

The Evolution of Vaccines Development across Salmonella Serovars among Animal Hosts: A Systematic Review

by Abubakar Siddique, Zining Wang, Haiyang Zhou, Linlin Huang, Chenghao Jia, Baikui Wang, Abdelaziz Ed-Dra, Lin Teng, Yan Li and Min Yue

Vaccines 2024, 12(9), 1067; https://doi.org/10.3390/vaccines12091067 - 18 Sep 2024

Abstract

Salmonella is a significant zoonotic foodborne pathogen, and the global spread of multidrug-resistant (MDR) strains poses substantial challenges, necessitating alternatives to antibiotics. Among these alternatives, vaccines protect the community against infectious diseases effectively. This review aims to summarize the efficacy of developed Salmonella [...] Read more.

Salmonella is a significant zoonotic foodborne pathogen, and the global spread of multidrug-resistant (MDR) strains poses substantial challenges, necessitating alternatives to antibiotics. Among these alternatives, vaccines protect the community against infectious diseases effectively. This review aims to summarize the efficacy of developed Salmonella vaccines evaluated in various animal hosts and highlight key transitions for future vaccine studies. A total of 3221 studies retrieved from Web of Science, Google Scholar, and PubMed/Medline databases between 1970 and 2023 were evaluated. One hundred twenty-seven qualified studies discussed the vaccine efficacy against typhoidal and nontyphoidal serovars, including live-attenuated vaccines, killed inactivated vaccines, outer membrane vesicles, outer membrane complexes, conjugate vaccines, subunit vaccines, and the reverse vaccinology approach in different animal hosts. The most efficacious vaccine antigen candidate found was recombinant heat shock protein (rHsp60) with an incomplete Freund’s adjuvant evaluated in a murine model. Overall, bacterial ghost vaccine candidates demonstrated the highest efficacy at 91.25% (95% CI = 83.69–96.67), followed by the reverse vaccinology approach at 83.46% (95% CI = 68.21–94.1) across animal hosts. More than 70% of vaccine studies showed significant production of immune responses, including humoral and cellular, against Salmonella infection. Collectively, the use of innovative methods rather than traditional approaches for the development of new effective vaccines is crucial and warrants in-depth studies. Full article

(This article belongs to the Special Issue Animal Vaccines)

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26 pages, 4463 KiB

Open AccessArticle

Messaging to Reduce Booster Hesitancy among the Fully Vaccinated

by Chao Qin, Susan Joslyn, Jee Hoon Han, Sonia Savelli and Nidhi Agrawal

Vaccines 2024, 12(9), 1066; https://doi.org/10.3390/vaccines12091066 - 18 Sep 2024

Abstract

Vaccine hesitancy was a serious problem in the United States throughout the COVID-19 pandemic, due in part to the reduction in public trust in science that accompanied the pandemic. Now we are facing a new, similar but more extensive problem: booster hesitancy. Even [...] Read more.

Vaccine hesitancy was a serious problem in the United States throughout the COVID-19 pandemic, due in part to the reduction in public trust in science that accompanied the pandemic. Now we are facing a new, similar but more extensive problem: booster hesitancy. Even fewer Americans are current on the mRNA booster. We present the results of an experiment with residents of the US who received all initial doses of the mRNA vaccine but who were not up to date on the booster. Participants read a scientific explanation describing either the safety or the effectiveness of the boosters or nothing in the control group. The explanations significantly increased (compared to the control) participants’ perceptions of the safety and effectiveness of the mRNA booster, as well as their willingness to get boosted. Explanations also improved emotions and attitudes toward the booster. Furthermore, although liberals were significantly more willing to get boosted than were conservatives, improvement due to the explanations was similar across political ideology groups. However, when interactions were observed, conservatives increased to a greater degree. Importantly, the explanations increased participants’ perception of scientists’ expertise and knowledge, as well as participants’ trust in scientists and the vaccine technology. Full article

(This article belongs to the Special Issue Acceptance and Hesitancy in Vaccine Uptake)

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11 pages, 3063 KiB

Open AccessArticle

Enhanced Antimicrobial Peptide Response Following Bacillus Calmette–Guerin Vaccination in Elderly Individuals

by Arul Nancy Pandiarajan, Nathella Pavan Kumar, Anuradha Rajamanickam, Perumal Kannabiran Bhavani, Bharathi Jeyadeepa, Nandhini Selvaraj, Dinesh Asokan, Srikanth Tripathy, Chandrasekharan Padmapriyadarsini and Subash Babu

Vaccines 2024, 12(9), 1065; https://doi.org/10.3390/vaccines12091065 - 18 Sep 2024

Abstract

Background: Antimicrobial peptides are an important component of host defense against Mycobacterium tuberculosis. However, the ability of BCG to induce AMPs as part of its mechanism of action has not been investigated in detail. Methods: We investigated the impact of Bacillus Calmette–Guerin (BCG) [...] Read more.

Background: Antimicrobial peptides are an important component of host defense against Mycobacterium tuberculosis. However, the ability of BCG to induce AMPs as part of its mechanism of action has not been investigated in detail. Methods: We investigated the impact of Bacillus Calmette–Guerin (BCG) vaccination on circulating plasma levels and TB-antigen stimulated plasma levels of AMPs in a healthy elderly population. We assessed the association of AMPs, including Human Beta Defensin 2 (HBD-2), Human Neutrophil Peptide 1-3 (HNP1-3), Granulysin, and Cathelicidin (LL37), in circulating plasma and TB-antigen stimulated plasma (using IGRA supernatants) at baseline (pre-vaccination) and at Month 1 and Month 6 post vaccination. Results: Post BCG vaccination, both circulating plasma levels and TB-antigen stimulated plasma levels of AMPs significantly increased at Month 1 and Month 6 compared to pre-vaccination levels in the elderly population. However, the association of AMP levels with latent TB (LTB) status did not exhibit statistical significance. Conclusion: Our findings indicate that BCG vaccination is linked to heightened circulating levels of AMPs in the elderly population, which are also TB-antigen-specific. This suggests a potential mechanism underlying the immune effects of BCG in enhancing host defense against TB. Full article

(This article belongs to the Special Issue Research Progress of New Tuberculosis Vaccines and Vaccine Design)

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13 pages, 1180 KiB

Open AccessSystematic Review

Effectiveness of COVID-19 Vaccines in People with Severe Mental Illness: A Systematic Review and Meta-Analysis

by Wen Dang, Iman Long, Yiwei Zhao, Yu-Tao Xiang and Robert David Smith

Vaccines 2024, 12(9), 1064; https://doi.org/10.3390/vaccines12091064 - 18 Sep 2024

Abstract

Prior to the introduction of COVID-19 vaccines, patients with severe mental illness (SMI) were at greater risk of COVID-19-related outcomes than the general population. It is not yet clear whether COVID-19 vaccines have reduced the risk gap. We systematically searched nine international databases [...] Read more.

Prior to the introduction of COVID-19 vaccines, patients with severe mental illness (SMI) were at greater risk of COVID-19-related outcomes than the general population. It is not yet clear whether COVID-19 vaccines have reduced the risk gap. We systematically searched nine international databases and three Chinese databases to identify relevant studies from December 2020 to December 2023 to compare the risk of COVID-19-related outcomes for SMI patients to those without SMI after vaccination. Random effects meta-analysis was performed to estimate the pooled odds ratio (OR) with 95% confidence intervals (CI). Subgroup analysis, sensitivity analysis, and publication bias analysis were conducted with R software 4.3.0. A total of 11 observational studies were included. Compared with controls, SMI patients were associated with a slightly increased risk of infection (pooled OR = 1.10, 95% CI, 1.03–1.17, I² = 43.4%), while showing a 2-fold higher risk of hospitalization (pooled OR = 2.66, 95% CI, 1.13–6.22, I² = 99.6%), even after both groups have received COVID-19 vaccines. Limited evidence suggests a higher mortality risk among SMI patients compared to controls post vaccination, but the findings did not reach statistical significance. SMI patients remain at increased risk compared to their peers in COVID-19-related outcomes even after vaccination. Vaccination appears an effective approach to prevent severe COVID-19 illness in SMI patients, and actions should be taken by healthcare providers to improve vaccination coverage in these vulnerable groups. Full article

(This article belongs to the Section COVID-19 Vaccines and Vaccination)

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21 pages, 4894 KiB

Open AccessArticle

Development of a Two-Component Nanoparticle Vaccine Displaying an HIV-1 Envelope Glycoprotein that Elicits Tier 2 Neutralising Antibodies

by Kegomoditswe Malebo, Jeremy Woodward, Phindile Ximba, Qiniso Mkhize, Sanele Cingo, Thandeka Moyo-Gwete, Penny L. Moore, Anna-Lise Williamson and Rosamund Chapman

Vaccines 2024, 12(9), 1063; https://doi.org/10.3390/vaccines12091063 - 18 Sep 2024

Abstract

Despite treatment and other interventions, an effective prophylactic HIV vaccine is still an essential goal in the control of HIV. Inducing robust and long-lasting antibody responses is one of the main targets of an HIV vaccine. The delivery of HIV envelope glycoproteins (Env) [...] Read more.

Despite treatment and other interventions, an effective prophylactic HIV vaccine is still an essential goal in the control of HIV. Inducing robust and long-lasting antibody responses is one of the main targets of an HIV vaccine. The delivery of HIV envelope glycoproteins (Env) using nanoparticle (NP) platforms has been shown to elicit better immunogenicity than soluble HIV Env. In this paper, we describe the development of a nanoparticle-based vaccine decorated with HIV Env using the SpyCatcher/SpyTag system. The Env utilised in this study, CAP255, was derived from a transmitted founder virus isolated from a patient who developed broadly neutralising antibodies. Negative stain and cryo-electron microscopy analyses confirmed the assembly and stability of the mi3 into uniform icosahedral NPs surrounded by regularly spaced CAP255 gp140 Env trimers. A three-dimensional reconstruction of CAP255 gp140 SpyTag–SpyCatcher mi3 clearly showed Env trimers projecting from the centre of each of the pentagonal dodecahedral faces of the NP. To our knowledge, this is the first study to report the formation of SpyCatcher pentamers on the dodecahedral faces of mi3 NPs. To investigate the immunogenicity, rabbits were primed with two doses of DNA vaccines expressing the CAP255 gp150 and a mosaic subtype C Gag and boosted with three doses of the NP-developed autologous Tier 2 CAP255 neutralising antibodies (Nabs) and low levels of heterologous CAP256SU NAbs. Full article

(This article belongs to the Special Issue Virus-Like Particle (VLP) Vaccines against Emerging Infectious Diseases)

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4 pages, 163 KiB

Open AccessEditorial

“Humanly Possible”: Geographies, Metrics and Methods to Address Immunization Inequalities

by Devaki Nambiar, Ahmad Reza Hosseinpoor, Nicole Bergen, M. Carolina Danovaro-Holliday, Ciara E. Sugerman and Hope L. Johnson

Vaccines 2024, 12(9), 1062; https://doi.org/10.3390/vaccines12091062 - 18 Sep 2024

Abstract

The year 2024 marks the 50th anniversary of the World Health Organization (WHO) Expanded Program on Immunization (EPI) [...] Full article

(This article belongs to the Special Issue Inequality in Immunization 2024)

10 pages, 224 KiB

Open AccessArticle

Methotrexate and Tumor Necrosis Factor Inhibitors Independently Decrease Neutralizing Antibodies after SARS-CoV-2 Vaccination: Updated Results from the SUCCEED Study

by Carol A Hitchon, Dawn M. E. Bowdish, Gilles Boire, Paul R. Fortin, Louis Flamand, Vinod Chandran, Roya M. Dayam, Anne-Claude Gingras, Catherine M. Card, Inés Colmegna, Maggie J. Larché, Gilaad G. Kaplan, Luck Lukusa, Jennifer L.F. Lee, Sasha Bernatsky and on behalf of the SUCCEED Investigative Team

Vaccines 2024, 12(9), 1061; https://doi.org/10.3390/vaccines12091061 - 17 Sep 2024

Abstract

Objective: SARS-CoV-2 remains the third most common cause of death in North America. We studied the effects of methotrexate and tumor necrosis factor inhibitor (TNFi) on neutralization responses after COVID-19 vaccination in immune-mediated inflammatory disease (IMID). Methods: Prospective data and sera of adults [...] Read more.

Objective: SARS-CoV-2 remains the third most common cause of death in North America. We studied the effects of methotrexate and tumor necrosis factor inhibitor (TNFi) on neutralization responses after COVID-19 vaccination in immune-mediated inflammatory disease (IMID). Methods: Prospective data and sera of adults with inflammatory bowel disease (IBD), rheumatoid arthritis (RA), spondyloarthritis (SpA), psoriatic arthritis (PsA), and systemic lupus (SLE) were collected at six academic centers in Alberta, Manitoba, Ontario, and Quebec between 2022 and 2023. Sera from two time points were evaluated for each subject. Neutralization studies were divided between five laboratories, and each lab’s results were analyzed separately using multivariate generalized logit models (ordinal outcomes: absent, low, medium, and high neutralization). Odds ratios (ORs) for the effects of methotrexate and TNFi were adjusted for demographics, IMID, other biologics and immunosuppressives, prednisone, COVID-19 vaccinations (number/type), and infections in the 6 months prior to sampling. The adjusted ORs for methotrexate and TNFi were then pooled in random-effects meta-analyses (separately for the ancestral strains and the Omicron BA1 and BA5 strains). Results: Of 479 individuals (958 samples), 292 (61%) were IBD, 141 (29.4%) were RA, and the remainder were PsA, SpA, and SLE. The mean age was 57 (62.2% female). For both the individual labs and the meta-analyses, the adjusted ORs suggested independent negative effects of TNFi and methotrexate on neutralization. The meta-analysis adjusted ORs for TNFi were 0.56 (95% confidence interval (CI) 0.39, 0.81) for the ancestral strain and 0.56 (95% CI 0.39, 0.81) for BA5. The meta-analysis adjusted OR for methotrexate was 0.39 (95% CI 0.19, 0.76) for BA1. Conclusions: SARS-CoV-2 neutralization in vaccinated IMID was diminished independently by TNFi and methotrexate. As SARS-CoV-2 circulation continues, ongoing vigilance regarding optimized vaccination is required. Full article

(This article belongs to the Section Vaccine Efficacy and Safety)

12 pages, 239 KiB

Open AccessArticle

Pediatric Oncology Providers’ HPV Vaccine Knowledge, Attitude, Self-Efficacy, and Practice after Communication Training: A Comparison with a National Survey

by Rejane A. Teixeira, Allison Grimes, Leanne Embry, Christine Aguilar and L. Aubree Shay

Vaccines 2024, 12(9), 1060; https://doi.org/10.3390/vaccines12091060 - 17 Sep 2024

Abstract

Background/Objectives: Human papillomavirus (HPV) vaccinations prevent HPV infection and related cancers. Despite being at higher risk of secondary cancers linked to HPV, childhood cancer survivors (CCS) are undervaccinated. This study aimed to compare pediatric oncology providers’ knowledge, attitudes, self-efficacy, and practices regarding HPV [...] Read more.

Background/Objectives: Human papillomavirus (HPV) vaccinations prevent HPV infection and related cancers. Despite being at higher risk of secondary cancers linked to HPV, childhood cancer survivors (CCS) are undervaccinated. This study aimed to compare pediatric oncology providers’ knowledge, attitudes, self-efficacy, and practices regarding HPV vaccination among those who participated in a multilevel educational HPV vaccine program with those of a national sample of oncology providers. Methods: Between February and March 2023, 39 providers from five pediatric oncology clinics in Texas completed online surveys, assessing knowledge about CCS risk for HPV-related cancers, attitudes towards the HPV vaccine, and confidence in recommending the vaccine to CCS. The results were compared with a national survey of providers conducted in 2019 (n = 195). Results: The findings showed that providers who participated in our program had greater knowledge of CCS increased risk for HPV-related cancers (96% vs. 38%; p < 0.001); greater confidence in discussing and recommending the HPV vaccine (100% vs. 66%, p < 0.001) and addressing parental concerns (100% vs. 69%, p < 0.001); and a more positive attitude about oncology providers than general pediatricians, recommending (96% vs. 71%; p = 0.006) and administering the HPV vaccine to CCS (96% vs. 53%, p < 0.001). Conclusion: This study underscores the importance of educating oncology providers about the increased risk of CCS and improving their self-efficacy to recommend the HPV vaccine, promoting vaccination in the oncology setting. Full article

(This article belongs to the Special Issue Vaccine Strategies for HPV-Related Cancers)

17 pages, 2645 KiB

Open AccessArticle

Safety of COVID-19 Vaccines among People with History of Allergy: A European Active Surveillance Study

by Nicoletta Luxi, Francesco Ciccimarra, Chiara Bellitto, Monika Raethke, Florence van Hunsel, Thomas Lieber, Erik Mulder, Luca L’Abbate, Francisco Batel Marques, Fabiana Furci, Andreea Farcas, Janneke Giele-Eshuis, Kathryn Morton, Simona Sonderlichová, Nicolas H. Thurin, Felipe Villalobos, Fabio Riefolo, Miriam C. Sturkenboom and Gianluca Trifirò

Vaccines 2024, 12(9), 1059; https://doi.org/10.3390/vaccines12091059 - 17 Sep 2024

Abstract

Background: Conventional vaccines rarely cause severe allergic reactions. However, the rapid development and approval of COVID-19 vaccines left limited initial data on their adverse reactions, particularly in individuals with a history of allergy. The aim of this study was to assess and compare [...] Read more.

Background: Conventional vaccines rarely cause severe allergic reactions. However, the rapid development and approval of COVID-19 vaccines left limited initial data on their adverse reactions, particularly in individuals with a history of allergy. The aim of this study was to assess and compare the safety profile of different doses and brands of COVID-19 vaccines in subjects with a history of allergy vs. those without a history of allergy. Methods: From February 2021 to February 2023, a web-based prospective study gathered vaccinee-reported outcomes using electronic questionnaires across eleven European countries. Baseline and up to six follow-up questionnaires captured data on vaccinee demographics, as well as both solicited and unsolicited adverse reactions. Results: Overall, 3476 vaccinees with a history of allergy were matched with 13,872 vaccinees from the general population at the first vaccination cycle and were included in the analysis. A total of 825 vaccinees with a history of allergy who had received a booster dose, matched to 3297 vaccinees from the general population, were included in the analysis. Higher rates of ADRs occurred after the first vaccination cycle compared to after the booster dose (64–91% vs. 56–79%). However, most reported ADRs were solicited and not serious, and no case of anaphylaxis was reported. Women and vaccinees with a history of allergy reported ADRs more frequently than men and the matched controls, respectively. Compared to other COVID-19 vaccines, a higher proportion of vaccinees experiencing at least one ADR following their first vaccination cycle was observed with Comirnaty and Vaxzevria. Statistically significant differences were observed among the study cohorts for median TTO after the second dose, and for median TTR following the first vaccination cycle and booster dose (p < 0.001). Conclusions: Typically, any drug or vaccine use carries a risk of severe allergic reactions, yet the benefits of vaccination generally outweigh these potential risks, as shown with the COVID-19 vaccines. Full article

(This article belongs to the Section COVID-19 Vaccines and Vaccination)

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