Effective Vaccine Research Articles

A retrospective cohort study on the protective effect of influenza vaccination during pregnancy in Gansu Province

ABSTRACT To evaluate the Vaccine Effectiveness (VE) of the Influenza Vaccine (InfV) during pregnancy in Gansu province. A retrospective cohort of pregnant women vaccinated with InfV was constructed using the electronic case system and immunization planning system of Gansu province. Outcome information of Influenza-Like Illness (ILI) in pregnant women after vaccination with InfV during the influenza epidemic seasons from 2019 to 2021 was collected. The log-binomial model was used to estimate the adjusted Risk Ratio (RR), VE, and their Confidence Intervals (CI). The incidence rates of the InfV vaccination group and the non-vaccination group during pregnancy in Gansu province were 4.70% (54/1,150) and 6.91% (16,990/245,754), respectively. The adjusted RR was 0.78 (95%CI 0.43–0.75), and the adjusted VE was 22.20 (95%CI 0.79–40.30). Vaccination with InfV during pregnancy in Gansu province from 2019 to 2021 has a protective effect against ILI in pregnant women, and there is no difference in vaccination at different stages of pregnancy.

Understanding Natural Immunity against Malaria: Mechanisms, Implications, and Future Directions

Malaria remains a significant global health challenge, particularly in sub-Saharan Africa, where it contributes to high morbidity and mortality rates. Natural immunity to malaria, acquired through repeated exposure to Plasmodium parasites, provides partial protection against severe disease but does not prevent infection. This review explores the mechanisms underlying natural immunity, including the roles of innate and adaptive immune responses, and the impact of factors such as age, genetics, and repeated exposure. It also examines the implications of natural immunity for malaria control strategies, particularly in endemic regions where partial immunity helps reduce the disease burden. The review highlights recent advances in immunological research, including the identification of immune markers and biomarkers that correlate with malaria resistance. Additionally, it discusses how natural immunity can inform the development of more effective vaccines and therapies. The review concludes by identifying key gaps in current research and suggesting future directions, including enhancing natural immunity through vaccines and immunotherapies, and the importance of global collaboration in advancing malaria control efforts. Keywords: Malaria, Natural immunity, Innate immunity, Adaptive immunity, Plasmodium parasites, Vaccine development.

Minimalist Adjuvant-Free Nano-Vaccine Based on Antigen Self-Assembled Amyloid-Like Fibrils to Induce Potent Immune Response.

The development of cancer vaccines is at the forefront of cancer immunotherapy. Most existing strategies to induce an efficient anti-tumor immune response rely on molecular adjuvants and the incorporation of complex synthetic vectors into vaccine formulations. In contrast, this study introduces a one-step engineering technique to assemble the model antigen, Ovalbumin (OVA), into amyloid aggregates, leveraging biomimetic folding and aggregation to create non-fibrillar OVA globular aggregates and OVA amyloid-like fibrils as single-component, adjuvant-free vaccines. Notably, the OVA amyloid-like fibrils induced stronger immune responses compared to the native form, as evidenced by robust humoral immune reactions and the establishment of immune memory. These enhanced responses can be attributed to the self-adjuvant effect of the unique assembled structure, which preserves antigenic epitopes, improves antigen stability, facilitates antigen internalization, prolongs retention at the injection site, enhances antigen trafficking to the lymphoid organs, and promotes increased secretion of antibodies and cytokines. Furthermore, the efficacy of the vaccine was validated in a high OVA-expressing tumor model, demonstrating the potential of OVA amyloid-like fibrils as an effective vaccine for cancer immunoprevention. This minimalist self-adjuvant vaccine strategy holds promising implications for cancer immunotherapy and can inform the design of other protein antigen-based vaccines.

Effectiveness of BNT162b2 XBB vaccine in the US Veterans Affairs Healthcare System

Data evaluating effectiveness of XBB.1.5-adapted vaccines against JN.1-related endpoints are scarce. This nationwide test-negative case-control study within the US Veterans Affairs Healthcare System aims to estimate vaccine effectiveness (VE) of BNT162b2 XBB.1.5-adapted vaccine compared to not receiving an XBB vaccine of any kind against COVID-19 hospitalization, emergency department or urgent care visits (ED/UC), and outpatient visits. Between September 25, 2023 and January 31, 2024, effectiveness was 24–35% during a period of JN.1 predominance and 50–61% during XBB predominance across all outcomes. VE within 60 days of vaccination during the likely JN.1 period was 32% (95% confidence interval 3–52%) against hospitalization, 41% (23–54%) against ED/UC visits, and 31% (1–52%) against outpatient visits. Corresponding VE during the likely XBB period was 62% (44–74%), 52% (37–63%), and 50% (25–66%) by setting, respectively. Here, we show the importance of strain match to maximize the public health impact of COVID-19 vaccination.

Virologic Response and Safety of Ibuzatrelvir, a Novel SARS-CoV-2 Antiviral, in Adults With COVID-19.

Despite effective vaccines and treatments for COVID-19, clinical burden persists. An unmet need exists for additional effective agents with safety profiles allowing use across a broad population. Ibuzatrelvir is an orally bioavailable SARS-CoV-2 Mpro inhibitor that has demonstrated in vitro antiviral activity and low potential for safety concerns, including drug-drug interactions. This phase 2b, double-blind, randomized clinical trial enrolled US adults aged 18‒<65 years with symptomatic COVID-19 and no risk factors for severe disease. Participants were randomized 1:1:2:2 to receive 100, 300, or 600 mg ibuzatrelvir or placebo orally twice daily for 5 days. Nasopharyngeal specimens were collected on Days 1 (baseline), 3, 5, 10, 14, and 21; adverse events (AEs) were recorded through Day 33. The primary endpoint was change in SARS-CoV-2 RNA level (viral load [VL]) from baseline to Day 5 among participants with baseline VL ≥4 log10 copies/mL. Of 240 enrollees, 237 received ≥1 dose and 199 were included in the primary analysis. Placebo-adjusted least squares mean (80% CI) change from baseline in VL at Day 5 was significant across all doses: 100 mg, ‒0.7 (‒1.1, ‒0.3) log10 copies/mL, P=0.02; 300 mg, ‒0.8 (‒1.3, ‒0.3) log10 copies/mL, P=0.01; and 600 mg, ‒1.2 (‒1.5, ‒0.8) log10 copies/mL, P<0.0001. AEs occurred in similar percentages of participants across groups. No deaths from any cause or treatment-related serious AEs occurred through Day 33, and no participants reported dysgeusia. All 3 ibuzatrelvir doses were associated with robust antiviral activity and an acceptable safety profile, supporting continued clinical development. Clinicaltrials.gov identifier: NCT05799495.

Challenges in Influenza Control and Surveillance in the Republic of Kazakhstan

The COVID-19 pandemic has significantly disrupted the circulation of influenza viruses in Kazakhstan, highlighting the vulnerabilities in the country’s public health infrastructure. This review critically examines the challenges faced in infiltrating and controlling influenza in Kazakhstan, particularly in light of the shifting epidemiological landscape post-pandemic. Key issues include the decline in influenza cases during the pandemic, which complicates the assessment of influenza epidemiology, vaccine effectiveness, and planning of vaccination campaigns. Although part of the Global Influenza Hospital Surveillance Network (GIHSN), Kazakhstan's surveillance systems face data collection, coordination, and public awareness gaps. The review discusses the prevalence of various influenza strains, the impact of zoonotic infections, and the necessity for improved monitoring frameworks. Additionally, the historical context of infectious disease control in Kazakhstan is explored, emphasising the need for enhanced international collaboration and targeted public health strategies. The findings underscore the importance of vaccination and robust surveillance to mitigate the risks of seasonal and pandemic influenza, advocating for a comprehensive approach to safeguard public health in Kazakhstan.

How Does African Swine Fever Virus Evade the cGAS-STING Pathway?

African swine fever (ASF), a highly infectious and devastating disease affecting both domestic pigs and wild boars, is caused by the African swine fever virus (ASFV). ASF has resulted in rapid global spread of the disease, leading to significant economic losses within the swine industry. A significant obstacle to the creation of safe and effective ASF vaccines is the existing knowledge gap regarding the pathogenesis of ASFV and its mechanisms of immune evasion. The cyclic GMP–AMP synthase (cGAS)–stimulator of interferon genes (STING) pathway is a major pathway mediating type I interferon (IFN) antiviral immune response against infections by diverse classes of pathogens that contain DNA or generate DNA in their life cycles. To evade the host’s innate immune response, ASFV encodes many proteins that inhibit the production of type I IFN by antagonizing the cGAS-STING signaling pathway. Multiple proteins of ASFV are involved in promoting viral replication by protein–protein interaction during ASFV infection. The protein QP383R could impair the function of cGAS. The proteins EP364R, C129R and B175L could disturb the function of cyclic guanosine monophosphate-adenosine monophosphate (cGAMP). The proteins E248R, L83L, MGF505-11R, MGF505-7R, H240R, CD2v, E184L, B175L and p17 could interfere with the function of STING. The proteins MGF360-11L, MGF505-7R, I215L, DP96R, A151R and S273R could affect the function of TANK Binding Kinase 1 (TBK1) and IκB kinase ε (IKKε). The proteins MGF360-14L, M1249L, E120R, S273R, D129L, E301R, DP96R, MGF505-7R and I226R could inhibit the function of Interferon Regulatory Factor 3 (IRF3). The proteins MGF360-12L, MGF505-7R/A528R, UBCv1 and A238L could inhibit the function of nuclear factor kappa B (NF-Κb).

Review of domestic test systems for detecting current or past SARS‑CoV‑2 infection using enzyme‑linked immunosorbent assay

Introduction. Rapid and reliable assessment of circulating antibody levels to SARS-CoV-2 remains the current challenge for monitoring and preventing the spread of COVID-19. As the risk of emergence and dissemination of new viral strains continues to grow, epidemiologic research is also becomes increasingly important. The enzyme-linked immunosorbent assay (ELISA) is useful to assess the vaccination effectiveness and the need for revaccination, the proportion of post-disease and vaccinated individuals, and to monitor population immunity. This article provides an overview of the local ELISA kits currently available for the detection of antibodies against SARS-CoV-2 viral proteins, with a comparison to the certified kit by Mediagnost Ltd. (Germany).The aim. Laboratory testing of seven domestic reagent kits for the determination of antibodies to SARS-CoV-2 viral proteins by ELISA in comparison with the certified test system “Anti-SARS-CoV-2 ELISA E 111-IVD” (Mediagnost Ltd., Reutlingen, Germany).Materials and methods. The study included 80 serum samples from conditionally healthy donors: experimental group (n=70, serum samples collected after 2019) and control group (n=10, serum samples collected before 2018). The experimental group is comprised of non-infected and post-disease individuals; a proportion of those were vaccinated against COVID-19.Results and conclusions. The data obtained indicate high reproducibility, sensitivity (100 %), and specificity for all domestic ELISA kits in detecting both post-disease (90–95 %) and vaccinated volunteers (100 %). The main quality criteria of the obtained results were comparable to those for the certified test system, “Anti-SARS-CoV-2 ELISA E 111-IVD” (Mediagnost Ltd., Germany). All kits detecting IgG to the receptor-binding domain (RBD) and to the S-glycoprotein were effective for the reliable assessment of antibody production after the vaccination. Kits for the detection of antibodies to the RBD and/or viral nucleocapsid are useful for identifying unvaccinated post-disease individuals.

Community intervention of a single-dose or 2-dose regimen of bivalent human papillomavirus vaccine in schoolgirls in Thailand: vaccine effectiveness 2 years and 4 years after vaccination.

With accumulating evidence of single-dose human papillomavirus (HPV) vaccine efficacy in young women, we conducted a community vaccine effectiveness study comparing HPV single-dose and 2-dose regimens (0 and 6 months) of a bivalent HPV vaccine among grade 8 schoolgirls (aged 13-14 years) in Thailand. In 2018, eligible grade 8 schoolgirls in Udon Thani (single dose) and Buri Ram (2 doses) provinces were offered HPV vaccine per assigned dose regimen. Concurrently, a cross-sectional survey for measuring baseline HPV prevalence was conducted in grade 10 (n = 2600) and grade 12 unvaccinated schoolgirls (n = 2000) in each province. HPV infection was assessed in first-void urine samples, tested by DNA polymerase chain reaction on the cobas 4800 system (Roche Molecular Diagnostics, Pleasanton, CA). All samples positive on the cobas system and an equal number of negative samples were also tested by Anyplex II HPV28 Detection (Seegene, Seoul, South Korea). The surveys were repeated in 2020 and 2022, when vaccinated grade 8 schoolgirls reached grade 10, and then subsequently grade 12, respectively. Vaccine effectiveness was estimated by comparing the weighted prevalence of HPV-16 or HPV-18 between grade-matched unvaccinated schoolgirls on the baseline survey (2018) and vaccinated schoolgirls in the year-2 (2020) and year-4 (2022) surveys. Adjustment methods were used in the analysis to account for potential differences in sexual behavior due to the noncontemporaneous comparison. The prevalence of HPV-16 and HPV-18 on the baseline survey among unvaccinated grade 10/grade 12 schoolgirls was 2.90% (95% confidence interval [CI] = 2.54% to 3.31%)/3.98% (95% CI = 3.52% to 4.49%) for Udon Thani and 3.87% (95% CI = 3.46% to 4.34%)/6.13% (95% CI = 5.56% to 6.75%) for Buri Ram. On the year-2 survey, the prevalence among vaccinated grade 10 schoolgirls was 0.57% (95% CI = 0.42% to 0.77%) for Udon Thani and 0.31% (95% CI = 0.21% to 0.47%) for Buri Ram. The 2-year postvaccination crude vaccine effectiveness for the single-dose regimen was estimated at 80.4% (95% CI = 73.9% to 86.9%), and for the 2-dose regimen at 91.9% (95% CI = 88.5% to 95.4%). On the year-4 survey, the prevalence among vaccinated grade 12 schoolgirls was 0.37% (95% CI = 0.25% to 0.56%) for Udon Thani and 0.28% (95% CI = 0.18% to 0.45%) for Buri Ram. Four-year postvaccination crude vaccine effectiveness for the single-dose regimen was estimated at 90.6% (95% CI = 86.6% to 94.6%) and for the 2-dose regimen was estimated at 95.4% (95% CI = 93.2% to 97.6%). All adjustment methods minimally affected vaccine effectiveness for the single-dose and 2-dose regimens. At 4 years after vaccination, the difference in crude vaccine effectiveness between the single-dose and 2-dose regimens was ‒4.79% (95% CI = ‒9.32% to ‒0.25%), meeting the study's noninferiority criteria. Our study demonstrated that both single-dose and 2-dose HPV vaccination significantly decreased HPV-16/18 point prevalence 2 years and 4 years after vaccination. Crude vaccine effectiveness at 4 years after vaccination was greater than 90% for both the single-dose and 2-dose regimens; the single-dose regimen was not inferior to the 2-dose regimen. These data show that a single dose of HPV vaccine provides high levels of protection when administered to schoolgirls younger than 15 years of age.

The role of leukocyte activation in suspected Non-IgE excipient-related COVID-19 vaccine reactions: An exploratory hypothesis-driven study of pathogenesis.

Background: Adverse allergic reactions due to the administration of vaccines developed for the protection of coronavirus disease 2019 (COVID-19) have been reported since the initiation of the vaccination campaigns in December 15, 2020. Current analyses provided by the Centers for Disease Control and Prevention and the U.S. Food and Drug Administration in the United States have estimated the rates of anaphylactic reactions in 2.5 and 11.1 per million of messenger RNA (mRNA) 1273 and BNT162b2 vaccines administered, respectively. The mechanisms by which these mRNA vaccines induce adverse vaccine reactions have been the subject of conflicting reports. Although skin testing with excipient components found in mRNA-1273 and BNT162b2 vaccines, such as polyethylene glycol (PEG) and related vaccine lipid products, were originally recommended to identify potential predictive biomarkers of adverse allergic reactions, more recent evidence has suggested that routine skin testing with these vaccine excipients have poor predictability and do not correlate with susceptibility to vaccine injury. Objective: The goal of this proof-of-concept (POC) exploratory study was to investigate the role of leukocyte activation (LA) induced by lipid excipients found in mRNA COVID-19 vaccines in the pathogenesis of COVID-19 mRNA vaccine-associated adverse reactions by using an LA assay developed in our laboratory. Results: An LA assay was performed on blood samples obtained from 30 study subjects who were assigned to three study groups: group 1 consisted of 10 subjects who had received an mRNA COVID-19 vaccine and developed a serious vaccine adverse reaction; group 2 consisted of 10 subjects who had received a COVID-19 vaccine and developed a mild adverse reaction; and group 3 consisted of 10 subjects who had not received a COVID-19 vaccine and were asymptomatic. Five excipients were tested in each of the 10 subjects; hence, a potential of 50 reactions could be expressed in each of the three groups. In the subjects in group 1 who had shown clinically severe vaccine effects, 8 of 50 (16%) had severe LA index (LAI) responses (>144.83), 12 of 50 (24%) had moderate LAI responses (87.62 -144.82), and 30 of 50 (60%) had no reaction (0 - 87.61). In the subjects in group 2 who had shown clinically mild vaccine effects, 4 of 50 (8%) had severe LAI responses (>144.83), 9 of 50 (18%) had moderate LAI responses (87.62 -144.82), and 37 of 50 (74%) had no reaction. In the subjects in group 3 who had not received the vaccine and, therefore, had no clinical vaccine effects, 2 of 50 (4%) had severe LAI responses (>144.83), 10 of 50 (20%) had moderate LAI responses (87.62 -144.82), and 38 of 50 (76%) had no reaction LA index (LAI) responses. Conclusion: The results of this exploratory POC study suggest that the measurement of LA induced by PEG and other vaccine-related lipid excipients found in mRNA COVID-19 vaccines may provide a novel and useful predictive biomarker associated with adverse non-immunoglobulin E (IgE) related allergic reactions to these vaccines. The study results also underscore growing concerns related to these non-IgE hypersensitivity reactions and their potential for pathogenesis of adverse vaccine reactions. This is particularly noteworthy because, with the continuing emergence of novel and evolving variants of severe acute respiratory syndrome corona-virus 2 mutants, yearly immunization with mRNA vaccines will most likely be recommended. Although the study was not sufficiently powered to draw definitive conclusions with regard to associations between vaccine-associated COVID-19 reactions and LA, the trends of a more severe set of clinical reactions seen associated with LAI reactivity scores, particularly with ALC-0159 (2-[{polyethylene glycol} 2000]-N,N-ditetradecylacetamide), suggest a potential benefit worthy of exploration in future randomized controlled trials.

Direct and indirect effects of hepatitis B vaccination in four low- and middle-income countries

Population-level vaccination effects of the hepatitis B vaccine were investigated in four low- and middle-income countries with different levels of vertical and horizontal transmission. Indirect vaccination effects constitute a large proportion of overall vaccination effects of the vaccination programmes in all four countries (over 70% by 2030 in all four countries). However, countries with higher levels of vertical transmission benefit less from indirect vaccination effects from the infant hepatitis B vaccine series during the first decades of the vaccination programme, making the birth dose vaccine more important in these countries. Vaccination, even at levels that do not fully control transmission, has a great effect on the development of disease as it also increases the average age of infection, thereby causing a decrease in the number of chronic infections relative to the number of acute infections.

Effectiveness of XBB.1.5 Vaccines Against Symptomatic SARS-CoV-2 Infection in Older Adults During the JN.1 Lineage-Predominant Period, European VEBIS Primary Care Multicentre Study, 20 November 2023-1 March 2024.

We estimated XBB.1.5 vaccine effectiveness (VE) against symptomatic SARS-CoV-2 infection among adults aged ≥ 65 years during the 2023/2024 JN.1 lineage-predominant period in a European multi-country test-negative case-control study at primary care level. We estimated VE adjusted by study site, age, sex, chronic conditions and onset date. We included 220 cases and 1733 controls. The VE was 48% (95% CI: 12-71), 23% (95% CI: -11-48) and 5% (95% CI: -92-56) among those with symptom onset 1-5, 6-11, and ≥ 12 weeks after vaccination, respectively. XBB.1.5 vaccine provided short and moderate protection against JN.1 symptomatic infection.

Effectiveness of Bivalent mRNA Vaccines in Preventing Symptomatic SARS-CoV-2 Infection-Increasing Community Access to Testing Program, United States, January-September 2023.

On September 2, 2022, bivalent COVID-19 mRNA vaccines, were recommended to address reduced effectiveness of COVID-19 monovalent vaccines during SARS-CoV-2 Omicron variant predominance. Using national pharmacy-based SARS-CoV-2 testing program data from January 15 to September 11, 2023, this test-negative, case-control design study assessed bivalent COVID-19 vaccine effectiveness (VE) against symptomatic infection. VE against symptomatic infection of a bivalent dose between 2 weeks and 1 month after bivalent vaccination ranged from 46% (95% CI: 38%-52%) for those aged ≥ 65 years to 61% (95% CI 41%-75%) for those aged 12-17 years. Bivalent vaccines protected against symptomatic infection. However, effectiveness waned over time, emphasizing the need to stay up to date with COVID-19 vaccination.

Current Updates on Variants of SARS-CoV- 2: Systematic Review.

Coronavirus disease 2019 is caused by the severe acute respiratory syndrome coronavirus 2, which has become a pandemic. Severe acute respiratory syndrome coronavirus 2 is an enveloped, unsegmented, positive-sense, single-stranded RNA virus that belongs to the family Coronaviridae. The objective of this review is to conduct a qualitative analysis of the current updates on epidemiology, evolution, and vaccine variants for SARS-CoV-2. The search strategy was done from the database based on the PRISMA criteria for qualitative analysis of this review. Literature on variants of severe acute respiratory syndrome coronavirus 2, published in English in the last 5 years (2019-2023), were included. From 179 a total of 105 articles were reviewed, searched, and retrieved from the electronic databases PubMed. The search was done using keywords like COVID-19, SARS-CoV-2, variants, mutations, and vaccines, and articles were managed using EndNote X8 software. The scope of view for this review was the course of the pandemic by emerging variants and how man is struggling to overcome this sudden pandemic through vaccines. The narrative skeleton was constructed based on the article's scope of view. From the parent severe acute respiratory syndrome coronavirus 2, many variants emerged during the course of this pandemic. They are mainly categorized into two variants: variants of interest and variants of concern based on the impact on public health. The World Health Organization leveled five variants: Alpha (strain B.1.1.7), Beta (strain B.1.351), Gamma (strain P.1), Delta (strain B.1.617.2), and Omicron (B.1.1.529). It is crucial to stay informed about the latest developments in the understanding of SARS-CoV-2 variants, as new variants can emerge and impact the course of the pandemic. Health authorities and researchers continuously have to monitor and study these variants to assess their characteristics, transmissibility, severity, and the effectiveness of vaccines against them. One has to always refer to the latest information from reputable health journals or organizations for the most up-to-date and accurate details on COVID-19 variants.

Effect of vaccination against Mycoplasma hyopneumoniae on divergent pig genetic groups

The bacterium Mycoplasma hyopneumoniae (Mhp) causes a chronic infectious respiratory disease in pigs, leading to important economic losses. This study aimed to compare the immune response of the local Piau breed and a commercial line to Mhp vaccination. For this, two phases were carried out. In the first, gene expression of toll-like receptors (TLR2, TLR4, TLR6, and TLR10) and cytokines (IL2, IL6, IL8, IL10, IL12, IL13, TNFα, and TGFβ) was assessed in porcine blood mononuclear cells (PBMC) from the two genetic groups before and after vaccination. In the second experiment, nitric oxide production, specific antibodies, and gene expression of toll-like receptors and cytokines were evaluated in bronchoalveolar lavage fluid (BALF) cells of vaccinated and unvaccinated pigs. After vaccination against Mhp, TLR2, TLR4, TLR6, TLR10, IL6, TNFα, and TGFβ expression levels were elevated in PBMC from commercial animals, and TLR6, TLR10, and TGFβ expression levels were elevated in PBMC from the Piau group. Vaccination also increased the production of Mhp-specific IgG antibodies in BALF cells in the Piau breed. Comparison of the two genetic groups revealed differences in TNFα and IL10 expression in BALF cells. These results show that Piau pigs have different immune responses to vaccination compared with commercial animals. It is worth noting that these genetic differences between both genetic groups may be related to phenotypic differences in Mhp resistance or susceptibility.

Evolutionary dynamics of voluntary vaccination for imperfect multi-efficacy vaccines

Voluntary vaccination is crucial for public health. The likelihood that the vaccinated get fully immune is typically referred to as the vaccine efficacy. In addition to this, the efficacy of vaccines also depends on inhibiting the transmission rates and protecting patients from critical symptoms. It has yet to be answered how the multi-efficacy of vaccines affects the vaccination behaviour. Here, we propose a game theoretical model of vaccination behaviour with a heterogeneous-transmission epidemiological process. Intuitively, individuals are likely to take vaccination for either high-efficient vaccines or epidemics with a large basic reproductive number. We find, however, a low economic discount rate can promote the uptake level for low-effectiveness vaccines and epidemics with small basic reproductive numbers. This result suggests that the perceived cost is more important than the risk of infection and the effectiveness of vaccines. In addition, we develop an analytical approximation to address the challenge arising from the coupled dynamics of vaccination and disease spread. This study shows how the interplay among three types of vaccine efficacies (transmission blocking, symptom mitigating and full immunity protecting) affects individual vaccination decisions and epidemic outcomes, and the model can be insightful for epidemic control.

Effectiveness of Original Monovalent and Bivalent COVID-19 Vaccines Against COVID-19-Associated Hospitalization and Severe In-Hospital Outcomes Among Adults in the United States, September 2022-August 2023.

Assessments of COVID-19 vaccine effectiveness are needed to monitor the protection provided by updated vaccines against severe COVID-19. We evaluated the effectiveness of original monovalent and bivalent (ancestral strain and Omicron BA.4/5) COVID-19 vaccination against COVID-19-associated hospitalization and severe in-hospital outcomes. During September 8, 2022 to August 31, 2023, adults aged ≥ 18 years hospitalized with COVID-19-like illness were enrolled at 26 hospitals in 20 US states. Using a test-negative case-control design, we estimated vaccine effectiveness (VE) with multivariable logistic regression adjusted for age, sex, race/ethnicity, admission date, and geographic region. Among 7028 patients, 2924 (41.6%) were COVID-19 case patients, and 4104 (58.4%) were control patients. Compared to unvaccinated patients, absolute VE against COVID-19-associated hospitalization was 6% (-7%-17%) for original monovalent doses only (median time since last dose [IQR] = 421 days [304-571]), 52% (39%-61%) for a bivalent dose received 7-89 days earlier, and 13% (-10%-31%) for a bivalent dose received 90-179 days earlier. Absolute VE against COVID-19-associated invasive mechanical ventilation or death was 51% (34%-63%) for original monovalent doses only, 61% (35%-77%) for a bivalent dose received 7-89 days earlier, and 50% (11%-71%) for a bivalent dose received 90-179 days earlier. Bivalent vaccination provided protection against COVID-19-associated hospitalization and severe in-hospital outcomes within 3 months of receipt, followed by a decline in protection to a level similar to that remaining from previous original monovalent vaccination by 3-6 months. These results underscore the benefit of remaining up to date with recommended COVID-19 vaccines.

The Effect of BCG Vaccination in the Elderly on Infectious and Non-Infectious Immune-Mediated Diseases

The Effect of BCG Vaccination in the Elderly on Infectious and Non-Infectious Immune-Mediated Diseases

Development and Evaluation of a Novel Chimeric Genotype VII Newcastle Disease Vaccine: Overcoming Maternal Antibody Interference and Spray Administration

Newcastle disease virus (NDV) poses a significant threat to the poultry industry, with the emergence of genotype VII NDV leading to extensive outbreaks and economic losses. Vaccination is the primary means of controlling NDV, but the presence of maternal antibodies (MDAs) can interfere with the immunological effect of live virus vaccines. Thus, we constructed a chimeric NDV live virus vaccine, LX-OAI4S, by replacing the extracellular regions of the F and HN genes of the NDV LX strain with the corresponding regions of the A-VII vaccine strain. The chimeric vaccine LX-OAI4S demonstrated high genetic stability, good safety, and strong reproductive capacity in chicken embryos. The LX-OAI4S vaccine induced rapid antibody production in specific pathogen-free (SPF) and commercial chickens via the intranasal and intraocular (IN/IO) routes, with hemagglutination inhibition (HI) antibody titers reaching 4.71 ± 1.03 log2 at 7 days post-vaccination (dpv), significantly higher than those of the two classical vaccine strains La Sota and VG/GA. The LX-OAI4S vaccine group provided effective protection against the challenge of genotype VII NDV virulent strain JS2/06 and inhibited viral shedding. When administered via spray, the LX-OAI4S vaccine elicited high systemic immunity against NDV in both SPF and commercial chickens, effectively protecting against clinical disease and reducing viral shedding. The chickens were exposed to high-dose vaccine for spray vaccination, and no adverse reactions were observed after vaccination. Despite the presence of anti-NDV MDAs in chickens, the NDV-specific antibody titers were significantly greater in the vaccinated groups than in the unvaccinated group. The vaccine exhibited high immunogenicity and the potential to overcome maternal antibody interference. The LX-OAI4S vaccine is a promising candidate for an ND vaccine. Its administration via spray can effectively prevent the occurrence of ND, making it a valuable tool for the poultry industry.

Evaluating the effectiveness of an autogenous vaccine to prevent motile Aeromonas septicaemia in striped catfish (Pangasianodon hypophthalmus) formulated by using DNA fingerprints for bacterial inclusion

Evaluating the effectiveness of an autogenous vaccine to prevent motile Aeromonas septicaemia in striped catfish (Pangasianodon hypophthalmus) formulated by using DNA fingerprints for bacterial inclusion