Common Vaccine Research Articles

COVID-19 Vaccine Preferences in General Populations in Canada, Germany, the United Kingdom, and the United States: Discrete Choice Experiment.

Despite strong evidence supporting COVID-19 vaccine efficacy and safety, a proportion of the population remains hesitant to receive immunization. Discrete choice experiments (DCEs) can help assess preferences and decision-making drivers. We aim to (1) elicit preferences for COVID-19 vaccines in Canada, Germany, the United Kingdom, and the United States; (2) understand which vaccine attributes people there value; and (3) gain insight into the choices that different population subgroups make regarding COVID-19 vaccines. Participants in the 2019nCoV-408 study were aged ≥18 years; self-reported antivaccinationists were excluded. A DCE with a series of 2 hypothetical vaccine options was embedded into a survey to determine participant treatment preferences (primary objective). Survey questions covered vaccine preference, previous COVID-19 experiences, and demographics, which were summarized using descriptive statistics to understand the study participants' backgrounds. In the DCE, participants were provided choice pairs: 1 set with and 1 without an "opt-out" option. Each participant viewed 11 unique vaccine profiles. Vaccine attributes consisted of type (messenger RNA or protein), level of protection against any or severe COVID-19, risk of side effects (common and serious), and potential coadministration of COVID-19 and influenza vaccines. Attribute level selections were included for protection and safety (degree of effectiveness and side effect risk, respectively). Participants were stratified by vaccination status (unvaccinated, or partially or fully vaccinated) and disease risk group (high-risk or non-high-risk). A conditional logit model was used to analyze DCE data to estimate preferences of vaccine attributes, with the percentage relative importance calculated to allow for its ranking. Each model was run twice to account for sets with and without the opt-out options. The mean age of participants (N=2000) was 48 (SD 18.8) years, and 51.25% (1025/2000) were male. The DCE revealed that the most important COVID-19 vaccine attributes were protection against severe COVID-19 or any severity of COVID-19 and common side effects. Protection against severe COVID-19 was the most important attribute for fully vaccinated participants, which significantly differed from the unvaccinated or partially vaccinated subgroup (relative importance 34.8% vs 30.6%; P=.049). Avoiding serious vaccine side effects was a significantly higher priority for the unvaccinated or partially versus fully vaccinated subgroup (relative importance 10.7% vs 8.2%; P=.044). Attributes with significant differences in the relative importance between the high-risk versus non-high-risk subgroups were protection against severe COVID-19 (38.2% vs 31.5%; P<.000), avoiding common vaccine side effects (12% vs 20.5%; P<.000), and avoiding serious vaccine side effects (9.7% vs 7.5%; P=.002). This DCE identified COVID-19 vaccine attributes, such as protection against severe COVID-19, that may influence preference and drive choice and can inform vaccine strategies. The high ranking of common and serious vaccine side effects suggests that, when the efficacy of 2 vaccines is comparable, safety is a key decision-making factor.

A mathematical model simulating the adaptive immune response in various vaccines and vaccination strategies

Vaccination has been widely recognized as an effective measure for preventing infectious diseases. To facilitate quantitative research into the activation of adaptive immune responses in the human body by vaccines, it is important to develop an appropriate mathematical model, which can provide valuable guidance for vaccine development. In this study, we constructed a novel mathematical model to simulate the dynamics of antibody levels following vaccination, based on principles from immunology. Our model offers a concise and accurate representation of the kinetics of antibody response. We conducted a comparative analysis of antibody dynamics within the body after administering several common vaccines, including traditional inactivated vaccines, mRNA vaccines, and future attenuated vaccines based on defective interfering viral particles (DVG). Our findings suggest that booster shots play a crucial role in enhancing Immunoglobulin G (IgG) antibody levels, and we provide a detailed discussion on the advantages and disadvantages of different vaccine types. From a mathematical standpoint, our model proposes four essential approaches to guide vaccine design: enhancing antigenic T-cell immunogenicity, directing the production of high-affinity antibodies, reducing the rate of IgG decay, and lowering the peak level of vaccine antigen-antibody complexes. Our study contributes to the understanding of vaccine design and its application by explaining various phenomena and providing guidance in comprehending the interactions between antibodies and antigens during the immune process.

Mobile Apps for Vaccination Services: Content Analysis and Quality Assessment.

Vaccination services are increasingly in demand by the public, and mobile apps are an effective tool to meet that demand. However, the characteristics and quality of these apps are unknown. Commonly used vaccination service apps on the market were surveyed with regard to quality, service content, and user experience to evaluate and guide users. The Qimai Data mobile app data analytics platform was used to search for common vaccination service apps by keyword, and the WeChat and Alipay platforms were searched for apps. The apps included in the study were independently evaluated by two reviewers using the Mobile Application Rating Scale, and the service content and user experience of the apps were analyzed. The intragroup correlation coefficient between raters was used to measure interrater reliability. In the app stores of the four major Android platforms and the iOS app store, 1092 and 207 apps were found, respectively; 189 WeChat applets and 30 Alipay applets were also found. A total of 29 apps was ultimately included in this study according to the inclusion criteria, including 21 independent apps, 4 WeChat applets, and 4 Alipay applets. Significant differences were found between independent apps and applets in terms of the quality score (t449.57=-5.301; P<.001) and the subjective quality score (z=-4.753; P<.001). No significant differences were found between iOS and Android platforms in terms of the quality score (t1404=-2.55; P=.80) and the subjective quality score (z=-0.137; P=.89). There was good intragroup consistency among the raters. In this study, independent apps and nonindependent apps that rely on social and payment platforms for implementation were included in the vaccination services category. The overall quality of these apps was acceptable. Nonindependent running apps were found to have slightly lower scores and showed room for improvement, and scores for the participatory apps were found to be generally low overall.

Neutralizing antibody titers after COVID-19 vaccination

BackgroundMonitoring COVID-19 and evaluating the effectiveness of prevention and control strategies are considered critical priorities in public health. As a result, the administration of COVID-19 vaccines has been widely approved around the world. In the current study, we investigated the level of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) neutralizing antibody (NAb) among individuals who received different COVID-19 vaccines. MethodsThis cross-sectional study recorded demographical data and clinical characteristics of 168 individuals who received COVID-19 vaccines from 2021 to 2022. Vaccination data of participants, including type and times of vaccine and any complications and symptoms after vaccination, were also recorded. SARS-CoV-2 NAb level was assessed by performing an ELISA test, and all data was analyzed using SPSS version 21. The significant level was set at 0.05. ResultsThe mean age of the participants was 40.4 ± 16 years, and 109 were females. About 18.4% of participants had the underlying diseases, of which thyroid diseases were the most frequent. The mean SARS-CoV-2 NAb level was 31.6 ± 39.78 ng/ml. Sinopharm was the common vaccine in our population, and AstraZeneca represented a high level of Nab 47.18 ng/ml. Among the participants, 96 had mild to severe complications after vaccination, with the most complaining of arm pain. Significant differences of NAb levele were observed only between types of vaccine and gender (P<0.05). ConclusionDue to our findings, all employed vaccines demonstrated efficacy in generating NAb. The levels of Nab were different among genders, age groups, and different types of vaccine receivers.

Surveillance of adverse events following varicella vaccine immunization in Jiangsu province, China from 2017 to 2023

To assess the safety of varicella vaccine (VarV) by conducting post-marketing surveillance on adverse events following immunization (AEFI) in Jiangsu Province, China.MethodsWe utilized the AEFI Information System of mainland China to monitor and categorize adverse reactions associated with VarV.ResultsThe incidence rate of AEFI was significantly higher after the first dose (48.79/100,000 doses) compared to the second dose (45.18/100,000 doses) (χ2 = 4.63, P = 0.031). Regional variations in AEFI incidence were observed within Jiangsu Province. Common reactions comprised 90.96% of AEFIs, while rare reactions and coincidental events accounted for 6.59% and 0.51%, respectively. Notably, there were no adverse events linked to vaccine quality, program errors, psychogenic reactions, or fatalities. Over 96% of AEFIs occurred within three days of VarV administration, with redness at the injection site (2.6 cm to 5 cm in diameter) being the most frequently observed symptom.ConclusionVarV demonstrates a commendable safety profile. Although there was a slight increase in AEFI incidence between 2022 and 2023, common vaccine reactions were predominantly observed, and the rates of rare reactions remained very low.

Vaccines and allergy: Back to the right places.

Hypersensitivity reactions represent one of the most common causes of hesitancy for adherence to national vaccination programs. The majority of hypersensitivity reactions after vaccination are mild, and anaphylaxis is reported to be rare, although it remains challenging to estimate the frequency attributed to each single vaccine, either because of the lower number of administered doses of less common vaccines, or the administration of simultaneous vaccine in most of the vaccination programs. Although literature remains scattered, international consensus guides clinicians in identifying patients who might need the administration of vaccines in protected environments due to demonstrated hypersensitivity to vaccine components or adjuvants. Here we provide the current guidance on hypersensitivity reactions to vaccines and on vaccination of children with allergy disorders.

Vaccination status of patients with primary immunodeficiencies in Germany-amulticentric epidemiologic analysis.

Vaccinations represent an easily accessible, safe, and important method for preventing infections. Patients with primary immunodeficiencies (PID) are more susceptible to infections and should receive an extended spectrum of immunizations in many countries. Between January 2019 and May 2020, vaccination certificates of 70patients with PID from the regions of Würzburg and Hanover in Germany were evaluated. The patients were additionally surveyed regarding their attitude towards vaccinations and the communication with their physicians. Medical records were analyzed. Of the 70patients, 54(77%) suffered from common variable immunodeficiency, 30 (43%) were diagnosed with accompanying autoimmunity, 62(89%) had an increased susceptibility to infections, and 56 (80%) were on immunoglobulin substitution therapy. Seven patients (10%) had neither avaccination certificate nor were they able to recollect of their last vaccination. Only55 (79%) and43 (61%) patients stated that their rheumatologist or immunologist had recommended an influenza and apneumococcal vaccination, respectively. When asked about their overall trust in vaccinations on ascale of 0 to 10 (0 = very low, 10 = very high), the mean value was7.8. The most common vaccination was against tetanus in 63 (90%) patients, 49 (70%) had received vaccination against pneumococci, and 39 (56%) had received an influenza vaccination. Interestingly, 26patients (37%) were vaccinated against measles, even though this is contraindicated in most PID patients. Our data suggest that vaccination rates in this at-risk population are insufficient. Healthcare providers should emphasize vaccinations routinely when caring for these patients.

Conceptualizing vaccine champions from an implementation science perspective: Findings from a national survey of primary care health professionals

ObjectiveClinical champions are healthcare professionals who help their colleagues improve the delivery of evidence-based care. Because little is known about champions working in the context of adolescent vaccination, we sought to identify vaccine champion roles among primary care health professionals (PCHPs). MethodsIn 2022, we surveyed 2527 US PCHPs who serve adolescents. The survey assessed the extent to which respondents identified as vaccine champions and the activities they performed. Guided by the Consolidated Framework for Implementation Research, we used these data to categorize PCHPs as: champions who led projects to increase vaccination rates (“implementation leaders”); facilitating champions who more generally shared vaccination data, information, and encouragement (“facilitators”); or non-champions. We used multinomial logistic regression to identify correlates of being a leader or facilitator as opposed to a non-champion. ResultsAbout one-fifth (21%) of PCHPs were implementation leaders, one-quarter (25%) were facilitators, and the remainder (54%) were non-champions. Leaders were more common among PCHPs with medium or high versus low practice experience (31% and 36% versus 20%, both p < .01) and adolescent patient volume (29% and 39% versus 17%, both p < .01). Being a facilitator was also associated with higher practice experience and patient volume. Leaders and facilitators reported a similar number of barriers to their work (mean = 1.8 and 1.9, respectively), with time and competing quality metrics being most common. ConclusionsOur findings suggest that both implementation leaders and facilitators are common vaccine champions in adolescent primary care. These champions are more often found among PCHPs with higher experience and patient volume.

Post-Marketing Surveillance of Adverse Events Following Immunization with Haemophilus Influenzae Type b Conjugate Vaccine - China, 2010-2021.

The Haemophilus influenzae type b (Hib) conjugate vaccine is widely administered in China. We extracted data on Hib vaccine doses administered and adverse events following immunization (AEFI) reported between 2010 and 2021 from the Chinese National Immunization Information System (CNIIS). A descriptive analysis was conducted to examine the characteristics and incidence rates of AEFI with the Hib vaccine. In China, between 2010 and 2021, a total of 52,910 AEFIs with the Hib vaccine were reported, resulting in an overall AEFI reporting rate of 38.10 per 100,000 doses. Common (typically minor) and rare (potentially serious) vaccine reactions occurred at rates of 34.71 and 2.78 per 100,000 doses, respectively. Among the common vaccine reactions, the incidences of fever (axillary temperature ≥38.6 ℃), injection site redness and swelling (>2.5 cm in diameter), and injection site induration (>2.5 cm in diameter) were 11.93, 9.69, and 3.38 per 100,000 doses, respectively. Rare vaccine reactions included anaphylactic rash, angioedema, and febrile convulsion with reported incidences of 2.42, 0.10, and 0.05 per 100,000 doses, respectively. The incidence of serious rare vaccine reactions was 0.16 per 100,000 doses. The reported incidence of AEFI with the Hib vaccine was low, with the occurrence of serious rare adverse reactions also being markedly low throughout the period 2010-2021 in China.

Pathogenicity and molecular characterization of a GI-19 infectious bronchitis virus isolated from East China.

Infectious bronchitis virus (IBV) is responsible for avian infectious bronchitis, a disease prevalent in countries with intensive poultry farming practices. Given the presence of multiple genotypic strains in China, identifying the regionally dominant genotypes is crucial for the implementation of effective prevention and control measures. This study focuses on the IBV strain CK/CH/WJ/215, isolated from a diseased commercial chicken flock in China in 2021. The CK/CH/WJ/215 isolate was genetically characterized through complete S1 sequence analysis. Phylogenetic comparisons were made with prevalent vaccine strains (H120, LDT3-A, and 4/91). Glycosylation patterns in the S1 protein were also analyzed. Pathogenicity was assessed in 7-day-old specific-pathogen-free chicks, monitoring morbidity, mortality, and tissue tropisms. Phylogenetic analysis clustered the CK/CH/WJ/215 isolate within the GI-19 lineage. Identity with the vaccination strains H120, LDT3-A, and 4/91 was low (75.7%, 78.6%, and 77.5% respectively). Novel glycosylation sites at positions 138 and 530 were identified compared to H120 and LDT-A. The isolate demonstrated nephropathogenic characteristics, causing 100% morbidity and 73.3% mortality in SPF chicks, with broader tropisms in tissues including trachea, lungs, kidneys, and bursa of Fabricius. Comprehensive genetic and pathological investigations revealed significant differences between the CK/CH/WJ/215 isolate and common vaccine strains, including novel glycosylation sites and a strong multiorgan infective capability. These findings are crucial for understanding the evolutionary dynamics of IBV and developing more effective prevention and control strategies.

Inequality in Childhood Immunization Coverage: A Scoping Review of Data Sources, Analyses, and Reporting Methods.

Immunization through vaccines among children has contributed to improved childhood survival and health outcomes globally. However, vaccine coverage among children is unevenly distributed across settings and populations. The measurement of inequalities is essential for understanding gaps in vaccine coverage affecting certain sub-populations and monitoring progress towards achieving equity. Our study aimed to characterize the methods of reporting inequalities in childhood vaccine coverage, inclusive of the settings, data source types, analytical methods, and reporting modalities used to quantify and communicate inequality. We conducted a scoping review of publications in academic journals which included analyses of inequalities in vaccination among children. Literature searches were conducted in PubMed and Web of Science and included relevant articles published between 8 December 2013 and 7 December 2023. Overall, 242 publications were identified, including 204 assessing inequalities in a single country and 38 assessing inequalities across more than one country. We observed that analyses on inequalities in childhood vaccine coverage rely heavily on Demographic Health Survey (DHS) or Multiple Indicator Cluster Surveys (MICS) data (39.3%), and papers leveraging these data had increased in the last decade. Additionally, about half of the single-country studies were conducted in low- and middle-income countries. We found that few studies analyzed and reported inequalities using summary measures of health inequality and largely used the odds ratio resulting from logistic regression models for analyses. The most analyzed dimensions of inequality were economic status and maternal education, and the most common vaccine outcome indicator was full vaccination with the recommended vaccine schedule. However, the definition and construction of both dimensions of inequality and vaccine coverage measures varied across studies, and a variety of approaches were used to study inequalities in vaccine coverage across contexts. Overall, harmonizing methods for selecting and categorizing dimensions of inequalities as well as methods for analyzing and reporting inequalities can improve our ability to assess the magnitude and patterns of inequality in vaccine coverage and compare those inequalities across settings and time.

Serological responses to vaccination in children exposed in utero to ustekinumab or vedolizumab: cross-sectional analysis of a prospective multicentre cohort

Evidence on serological responses to vaccination in children exposed to ustekinumab (UST) or vedolizumab (VDZ) in utero is lacking. This multicentre prospective study aimed to assess the impact of prenatal exposure to UST or VDZ due to maternal inflammatory bowel disease (IBD) on serological responses to vaccination and other immunological parameters in exposed children. Children aged ≥ 1 year who were exposed in utero to UST or VDZ and completed at least 1-year of mandatory vaccination were included. We assessed the serological response to vaccination (non-live: tetanus, diphtheria, and Haemophilus influenzae B; live: mumps, rubella, and measles), whole blood count, and immunoglobulin levels. The control group comprised unexposed children born to mothers without IBD. A total of 23 children (median age, 25 months) exposed to UST (n = 13) or VDZ (n = 10) and 10 controls (median age, 37 months) were included. The serological response to vaccination was comparable between the UST and VDZ groups and controls, with an adequate serological response rate of ≥ 80%. Only children exposed to UST showed a slightly reduced serological response to mumps (67% vs. 86% in controls), whereas all children exposed to VDZ showed an adequate response. The majority of the exposed children had normal levels of individual immunoglobulin classes, similar to the controls. No severe pathology was observed in any of the children.Conclusion: Despite the limited sample size, our findings suggest that in utero exposure to VDZ or UST does not significantly impair the vaccine response or broader immunological parameters in exposed children.What is known:• Treatment with anti-TNF inhibitors during pregnancy does not appear to affect serologic response to vaccination in exposed children.• Evidence on the efficacy of vaccination in children exposed to ustekinumab or vedolizumab in utero is almost lacking.What is new:• Our findings suggest that in utero exposure to ustekinumab or vedolizumab does not significantly affect the serological responses to common childhood non-live (tetanus, Haemophilus influenzae B, diphtheria) and live vaccines (measles, mumps, rubella).• No major adverse effects on overall immunological health were observed in children exposed in utero to ustekinumab or vedolizumab.

Sustained chronic inflammation and altered childhood vaccine responses in children exposed to Zika virus

Congenital Zika virus (ZIKV) infection leads to severe newborn abnormalities, but its long-term impact on childhood immunity is not well understood. This study aims to investigate the serum proteomics in children exposed to ZIKV during pregnancy to understand potential immunological consequences during early childhood. The study included ZIKV-exposed infants (ZEI) at birth (n=42) and children exposed to ZIKV (ZEC) at two years of age (n=20) exposed to ZIKV during pregnancy, as well as healthy controls. Serum proteomic analysis was performed on these groups to assess inflammation and immune profiles. Additionally, antibody titres against two common childhood vaccines, DTaP and MMR, were measured in healthy controls (n=50) and ZEC (n=92) to evaluate vaccine-induced immunity. Results showed elevated inflammation in ZEI with birth abnormalities. Among ZEC, despite most having normal clinical outcomes at two years, their serum proteomics indicated a bias towards Th1-mediated immune responses. Notably, ZEC displayed reduced anti-Diphtheria toxin and anti-Clostridium tetani IgG levels against DTaP and MMR vaccines. They also exhibited lower antibody titres particularly against Th2-biased DTaP vaccines, but not Th1-biased MMR vaccines. In conclusion, the study highlights the long-term immunological consequences of congenital ZIKV exposure. Heightened inflammation was observed in ZEI with abnormalities at birth, while ZEC maintained a chronic Th1-biased immune profile. The impaired response to Th2-biased vaccines raises concerns about lasting effects of ZIKV exposure on immune responses. Consequently, there is a need for continued longitudinal clinical monitoring to identify potential immune-related complications arising from prenatal exposure to ZIKV. This work was partially funded by the National Institute of Allergy and Infectious Diseases (NIAID) and National Institute of Dental and Craniofacial Research (NIDCR).

Determination of Deamidation in Adjuvanted Vaccine Antigens through Isoaspartic Acid Quantification.

Deamidation is a post-translational chemical modification that occurs within proteins and can be influenced by many factors, including temperature and pH. In vaccines, deamidation is considered undesirable as it may lead to changes in structure, function, stability, and immunogenicity. Detecting deamidation in vaccines, especially adjuvanted vaccines, can be challenging due to the lack of simple quantitative techniques. In this study, the quantification of isoaspartic acid (isoAsp) was used to assess deamidation in model antigens in the presence and absence of common vaccine adjuvants. This study shows that the detection of isoAsp was possible in the presence of various types of adjuvants with little to no interference. High levels of isoAsp were detected in thermally and pH-stressed adjuvanted vaccines, suggesting significant deamidation and highlighting the stability-indicating capabilities of the assay. The quantification of isoAsp in stability programs of a vaccine drug product could possibly find applications in product shelf-life determination, using thermal kinetic modeling to predict deamidation over time. The ability to detect deamidation early in vaccine development enhances process improvements and ultimately improves the vaccine's stability. To summarize, this paper describes a rapid and simple method to determine deamidation in adjuvanted vaccines. This method could be applicable to formulation development, stability assessment, or shelf-life determination.

Association of COVID-19 Vaccination With Changes in Smell and Taste.

Since the introduction of vaccines for severe acute respiratory syndrome coronavirus 2in the United States, there has been significant vaccine hesitancy, in part due to fear of adverse effects. We sought to investigate the rates of smell and taste changes after COVID-19 vaccination compared to other common vaccines. Our study cohort included individuals identified by Current Procedural Terminology code in the TriNetX database receiving the COVID-19 first series, COVID-19 booster, influenza, tetanus, diphtheria, pertussis (TDAP), or pneumococcal vaccines between December 15, 2020, and August 15, 2023. After 1:1 propensity score matching, postvaccination incidence of disturbance of smell and taste was significantly less likely after COVID-19 first series vaccine compared to influenza (odds ratios, OR: 0.27 [95% confidence interval, CI: 0.20-0.36]), TDAP (OR: 0.35 [95% CI: 0.26-0.47]), and pneumococcal vaccines (OR: 0.17 [95% CI: 0.09-0.32]). Similarly, incidence of disturbance of smell and taste was significantly less likely after COVID-19 booster vaccine compared to the influenza (OR: 0.60 [95% CI: 0.48-0.76]), TDAP (OR: 0.63 [95% CI: 0.47-0.85]), and pneumococcal vaccines (OR: 0.44 [95% CI: 0.28-0.68]). This study builds upon the literature demonstrating the safety of COVID-19 vaccination.

Integrating Syrian refugees into Lebanon’s healthcare system 2011–2022: a mixed-method study

IntroductionThe Lebanese government estimates the number of Syrian refugees to be 1.5 million, representing 25% of the population. Refugee healthcare services have been integrated into the existing Lebanese health system. This study aims to describe the integration of Syrian refugee health services into the Lebanese national health system from 2011 to 2022, amid an ongoing economic crisis since 2019 and the COVID-19 pandemic.MethodsThis paper employs a mixed-methods approach drawing upon different data sources including: 1- document review (policies, legislation, laws, etc.); 2- semi-structured interviews with policymakers, stakeholders, and health workers; 3- focus group discussions with patients from both host and refugee populations; and 4- health systems and care seeking indicators.ResultsAlthough the demand for primary health care increased due to the Syrian refugee crisis, the provision of primary health care services was maintained. The infusion of international funding over time allowed primary health care centers to expand their resources to accommodate increased demand. The oversupply of physicians in Lebanon allowed the system to maintain a relatively high density of physicians even after the massive influx of refugees. The highly privatized, fragmented and expensive healthcare system has impeded Syrian refugees’ access to secondary and tertiary healthcare services. The economic crisis further exacerbated limits on access for both the host and refugee populations and caused tension between the two populations. Our findings showed that the funds are not channeled through the government, fragmentation across multiple financing sources and reliance on international funding. Common medications and vaccines were available in the public system for both refugee and host communities and were reported to be affordable. The economic crisis hindered both communities’ access to medications due to shortages and dramatic price increases.ConclusionIntegrating refugees in national health systems is essential to achieve sustainable development goals, in particular universal health coverage. Although it can strengthen the capacity of national health systems, the integration of refugees in low-resource settings can be challenging due to existing health system arrangements (e.g., heavily privatized care, curative-oriented, high out-of-pocket, fragmentation across multiple financing sources, and system vulnerability to economic shocks).

Impact of viral telomeric repeat sequences on herpesvirus vector vaccine integration and persistence.

Marek's disease virus (MDV) vaccines were the first vaccines that protected against cancer. The avirulent turkey herpesvirus (HVT) was widely employed and protected billions of chickens from a deadly MDV infection. It is also among the most common vaccine vectors providing protection against a plethora of pathogens. HVT establishes latency in T-cells, allowing the vaccine virus to persist in the host for life. Intriguingly, the HVT genome contains telomeric repeat arrays (TMRs) at both ends; however, their role in the HVT life cycle remains elusive. We have previously shown that similar TMRs in the MDV genome facilitate its integration into host telomeres, which ensures efficient maintenance of the virus genome during latency and tumorigenesis. In this study, we investigated the role of the TMRs in HVT genome integration, latency, and reactivation in vitro and in vivo. Additionally, we examined HVT infection of feather follicles. We generated an HVT mutant lacking both TMRs (vΔTMR) that efficiently replicated in cell culture. We could demonstrate that wild type HVT integrates at the ends of chromosomes containing the telomeres in T-cells, while integration was severely impaired in the absence of the TMRs. To assess the role of TMRs in vivo, we infected one-day-old chickens with HVT or vΔTMR. vΔTMR loads were significantly reduced in the blood and hardly any virus was transported to the feather follicle epithelium where the virus is commonly shed. Strikingly, latency in the spleen and reactivation of the virus were severely impaired in the absence of the TMRs, indicating that the TMRs are crucial for the establishment of latency and reactivation of HVT. Our findings revealed that the TMRs facilitate integration of the HVT genome into host chromosomes, which ensures efficient persistence in the host, reactivation, and transport of the virus to the skin.

Acceptability of a Future HIV Vaccine: A Rapid Scoping Review.

A HIV vaccine is not available yet, but perceptions of HIV vaccines will be important to explore before their roll-out for effective vaccine promotion. This article presents the findings of a rapid scoping review of the literature to identify individual, social, and vaccine-related factors associated with the acceptability of a future HIV vaccine. We searched 5 databases (Medline OVID, Embase, PsycINFO, Web of Science, and Cochrane) using relevant keywords and Medical Subject Headings. All articles, regardless of study design, publication year, and geographic location, were included if they examined HIV vaccine acceptability and its underlying factors. We retrieved 2386 unique articles, of which 76 were included in the final review. Perceived benefits (34.2%) and perceived susceptibility (25.0%) were primary individual factors of HIV vaccine acceptability. Misinformation (17.1%) and distrust (22.4%) regarding future HIV vaccines, HIV stigma (30.3%), and social support (10.5%) were social factors of HIV vaccine acceptability. Vaccine efficacy (42.1%), cost (28.9%), and side effects (67.1%) were common vaccine characteristics influencing HIV vaccine acceptability. Altruism (10.5%) and risk compensation (26.3%) were also key factors. Our analyses revealed that skeptical beliefs, negative perceptions, and misconceptions about HIV vaccines are real barriers to their acceptability. To alleviate HIV vaccine hesitancy and address trust concerns, strategic vaccine communication should be disseminated by trustworthy sources. Messages should impart accurate vaccine information and emphasize both individual and social benefits of HIV vaccination, as well as leverage social support in increasing willingness to get a future HIV vaccine.

How Real Are Allergic Reactions to Vaccine Components in Children? − Experiences of Clinicians

Objective − Vaccine components have the potential to induce allergic reactions, although such reactions are infrequent, especially anaphylactic reactions, which are very rare (occurring at a rate of 1 per million vaccine doses). The objective of this study was to assess objectively the frequency of allergic reactions to vaccine components in children with suspected allergic reactions to vaccine components. Materials andMethods − We retrospectively analyzed the medical records of 209 patients aged 1 to 18 years with suspected allergic reactions to vaccine components, who underwent the standardized diagnostic procedures and tests to common allergens and vaccine components at Srebrnjak Children`s Hospital, Zagreb, Croatia. Results − Of the 209 children vaccinated in the hospital setting, only two (0.95%) developed side effects during their hospital stay, and 2.63% with a positive history of IgE mediated vaccine allergy were positive for one of the components of the vaccine. Local reactions to the vaccine were the most frequent adverse events in our patients. 62.6% of them were referred due to a positive history of egg protein allergy. Conclusion − Allergic reactions to vaccine components are rare and mild in most cases. In patients with a suggestive history, it is important to choose appropriate diagnostic tests to determine if vaccination can be performed safely. Only patients at risk of egg protein anaphylaxis generally require medically supervised vaccination in a hospital facility. Patients with a history or a documented and immediate allergic reaction (&lt;4 h) require an allergy workup to avoid the risk of repeated anaphylaxis after further administration.

COVID-19 Vaccination in Patients with Inborn Errors of Immunity Reduces Hospitalization and Critical Care Needs Related to COVID-19: a USIDNET Report

BackgroundThe CDC and ACIP recommend COVID-19 vaccination for patients with inborn errors of immunity (IEI). Not much is known about vaccine safety in IEI, and whether vaccination attenuates infection severity in IEI.ObjectiveTo estimate COVID-19 vaccination safety and examine effect on outcomes in patients with IEI.MethodsWe built a secure registry database in conjunction with the US Immunodeficiency Network to examine vaccination frequency and indicators of safety and effectiveness in IEI patients. The registry opened on January 1, 2022, and closed on August 19, 2022.ResultsPhysicians entered data on 1245 patients from 24 countries. The most common diagnoses were antibody deficiencies (63.7%). At least one COVID-19 vaccine was administered to 806 patients (64.7%), and 216 patients received vaccination prior to the development of COVID-19. The most common vaccines administered were mRNA-based (84.0%). Seventeen patients were reported to seek outpatient clinic or emergency room care for a vaccine-related complication, and one patient was hospitalized for symptomatic anemia. Eight hundred twenty-three patients (66.1%) experienced COVID-19 infection. Of these, 156 patients required hospitalization (19.0%), 47 required ICU care (5.7%), and 28 died (3.4%). Rates of hospitalization (9.3% versus 24.4%, p < 0.001), ICU admission (2.8% versus 7.6%, p = 0.013), and death (2.3% versus 4.3%, p = 0.202) in patients who had COVID-19 were lower in patients who received vaccination prior to infection. In adjusted logistic regression analysis, not having at least one COVID-19 vaccine significantly increased the odds of hospitalization and ICU admission.ConclusionVaccination for COVID-19 in the IEI population appears safe and attenuates COVID-19 severity.