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Serotypic and Genomic Diversity of Vibrio anguillarum in Rainbow Trout Farms in Turkey: Implications for Vibriosis Control and Vaccine Candidate Selection.

Outbreaks of vibriosis caused by Vibrio anguillarum are a persistent constraint on rainbow trout (Oncorhynchus mykiss) aquaculture. However, information on the population structure of field strains in Turkey has been lacking. Here, we report the first systematic serotypic, proteomic, and genomic characterization of 23 V. anguillarum isolates collected over 10&#x2009;years from rainbow trout farms located in six major aquaculture regions of Turkey. Serological analyses based on microagglutination, supported by ELISA characterization of hyperimmune sera, identified a clear predominance of serotype O1, whereas isolate V12 exhibited a non-agglutinating, atypical O-antigen profile. Protein profiling (SDS-PAGE) and immunoblotting showed largely conserved whole-cell protein patterns among the isolates, but distinct immunogenic bands at 14, 18, and 40&#x2009;kDa were detected in isolates V18 and V21. Long-read whole-genome sequencing revealed that most Turkish isolates grouped within the global O1 clade, while V12, V25, and V28 isolates occupied more distant branches. Comparative genomics demonstrated a conserved core virulence gene set (RTX toxins, siderophore and iron-uptake systems, motility and adhesion factors, Type VI secretion system), with strain-dependent variation in accessory loci such as anguibactin and T6SS-I. Experimental infections of rainbow trout demonstrated significant differences in virulence among isolates (p&#x2009;<&#x2009;0.05), with the V18 isolate showing high, the V15 intermediate, and the V12 low-mortality rates. By elucidating the relationship among the serotype, immunogenic protein profiles, virulence gene repertoires, and in&#xa0;vivo pathogenicity, this study provides a comprehensive overview of the antigenic and genomic diversity of Vibrio anguillarum isolates from Turkey. Notably, the identification of V18 and V21 as promising candidate strains for further vaccine evaluation, characterized by high virulence and unique immunogenic features, provides a scientific foundation for the development of serotype-specific vaccination strategies to mitigate vibriosis-associated losses in aquaculture.

Animals

Development and protective efficacy of a live attenuated vaccine candidate against goose astrovirus.

Goose astrovirus (GAstV) is a significant pathogen affecting goslings by inducing visceral gout, yet no commercial vaccine is currently available. This study involved the serial passaging of the GAstV-GXNN strain in LMH cells to investigate alterations in viral replication, genomic stability, and pathogenicity, as well as to assess the potential of a vaccine candidate. The findings indicated that the viral titer increased progressively with each passage, reaching 107.35 TCID50/mL by the 120th passage (GAstV-GXNNP120). Whole-genome sequencing revealed the presence of 6, 19, 26, and 28 nucleotide mutations at the 30th, 60th, 90th, and 120th passages, respectively. Pathogenicity assays demonstrated a reduction in virulence with successive passages, culminating in the complete attenuation of GAstV-GXNNP120, which did not induce clinical signs or lesions in one-day-old goslings. Following five successive passages in goslings, the attenuated strain exhibited stable genetic characteristics without any reversion to virulence. Goslings aged one day, inoculated with GAstV-GXNNP120 at dosages ranging from 102.0 to 105.0 TCID50, developed neutralizing antibodies by the third day post-vaccination. Antibody levels increased in a dose-dependent manner, peaking at day 21 and remaining elevated through day 42. Challenge experiments utilizing the virulent GAstV-GXNN strain revealed that groups vaccinated with doses of 103.0 TCID50 and above achieved complete protection. These groups exhibited no clinical symptoms or pathological damage post-challenge, and both tissue viral loads and virus shedding levels were significantly reduced compared to the control group. Consequently, the minimum effective vaccination dose was established at 103.0 TCID50. These results provide a crucial foundation for the development of a live attenuated GAstV vaccine.

Animals

Pre-clinical immunogenicity and safety evaluation of H2 strain Hepatitis A Inactivated Vaccine in rhesus macaques.

BACKGROUND: Hepatitis A is a viral infection of the liver that can cause mild to severe illness. Currently, two types of HAV vaccines are used worldwide, inactivated hepatitis A vaccines, which are used in most countries, and live attenuated vaccines (H2 and L-A-1 strain), which are mainly used in China. The major disadvantage of live attenuated virus to cause secondary infections among contacts and mutation shifts of the live vaccine strain. The H2 strain was selected for the development of an inactivated hepatitis A vaccine to further reduce biosafety risks. Rhesus macaques high genomic homology with humans and the incubation period after hepatitis A vaccination and human natural infections are similar. We use rhesus macaques to assess immunogenicity and safety of the H2 strain Hepatitis A Inactivated Vaccine. METHODS: The vaccine was assessed in rhesus macaques, divided into four groups (n&#x202f;=&#x202f;10 per group): the control group (adjuvant buffer; aluminum content 0.35&#x202f;mg/mL; 2&#x202f;mL per dose), the low-dose group (320EU, 0.5&#x202f;mL of 640EU/mL with aluminum content 0.35&#x202f;mg/mL), the medium-dose group (640EU, 1&#x202f;mL of 640EU/mL with aluminum content 0.35&#x202f;mg/mL), and the high-dose group (1280EU, 2&#x202f;mL of 640EU/mL with aluminum content 0.35&#x202f;mg/mL). Animals were injected intramuscularly at multiple sites in the hind limbs and received four inoculations at 4-week intervals. Test items including Clinical indicators, immunogenicity indicators and Histopathological examination. RESULTS: No abnormalities were observed in any group in terms of general clinical condition throughout the study period except for slight decreases in body temperature after immunization. Hematological parameters, serum biochemistry indices, and histopathological findings showed fluctuated to different degrees of fluctuation after immunization across all groups. Immunogenicity assessments showed that the inactivated hepatitis A vaccine (H2) induced both humoral and cellular immune responses effectively, and the levels of antibodies increased with certain dose- and time-response trends. CONCLUSION: The inactivated hepatitis A vaccine (H2 strain, human diploid cell) was safe and immunogenic in non-human primates. The results provide strong preclinical support for the further clinical development of this vaccine candidate.

Animals

Genotype II Live-Attenuated ASFV Vaccine Bearing 24 Genes Deletion in 3 Independent Regions Is Able to Provide Complete Protection Against Homologous Lethal Challenge.

African swine fever (ASF) is an acute, febrile, and highly contagious infectious disease of swine with the etiological agent of African swine fever virus (ASFV). The mortality rate of virulent strains is as high as 100%. Strengthening biosafety is so far the most effective way to prevent and control ASF. Therefore, it is urgent to develop a safe and effective vaccine. In this study, a Genotype II live-attenuated ASF vaccine bearing 24 genes deletion in 3 independent regions was constructed based on the highly virulent Eurasian strain ASFV CN/GS 2018 backbone. The resulting mutant ASFV-&#x394;24 is characterized by complete deletion of 24 genes distributed in 3 genomic positions of 852 to 11&#x2009;468, 19&#x2009;732 to 22&#x2009;929, and 179&#x2009;519 to 180&#x2009;617, among which MGF100 and whole MGF300 families are pioneeringly removed. The ASFV-&#x394;24 displayed a delayed and reduced replication kinetics as well as aberrant icosahedral empty particles devoid of a nucleoid when compared to the parental virus. Animal experiments showed that ASFV-&#x394;24 was completely attenuated in animals as evidenced by stable body temperature and no ASF-compatible clinical signs in vaccinated pigs. The ASFV-&#x394;24 could provide complete homologous protection against lethal challenge, as vaccinated pigs demonstrated boosted antibody response, transient but low levels of viremia in blood and virus titers in organs as well as almost undetectable viral shedding. Gene deletions in multiple regions are helpful for prevention of virulence reversion. These results indicate that ASFV-&#x394;24 can be used as an effective and promising candidate vaccine to control the spread of ASFV.

Animals

CRISPR-Cas and Infectious Diseases: A Decade of Translational Advances in Molecular Biotechnology.

CRISPR-Cas systems have emerged as a versatile tool for diagnosing, treating, and preventing infectious diseases. This review highlights translational advancements in CRISPR-Cas-based applications, concentrating on the past decades in diagnostics, therapeutic genome editing, and vaccine development. The article highlights key platforms like DETECTR and SHERLOCK, which enable rapid, sensitive pathogen detection, and explores CRISPR-Cas9 systems in therapeutic strategies for directly targeting viral genomes and combating antimicrobial resistance. It also examines the role of CRISPR-Cas9 in engineering live-attenuated and personalized neoantigen vaccines. Principal findings demonstrate a clear progression from experimental proof-of-concept to preclinical applications primarily in CRISPR-based diagnostics and the engineering of live-attenuated vaccine candidates, whereas translation in CRISPR-based therapeutics and personalized neoantigen vaccines for infectious diseases remains at earlier, more exploratory stages. CRISPR-based diagnostics have progressed further toward clinical evaluation than therapeutics due to delivery and safety constraints, while personalized neoantigen vaccines are included mainly as an emerging, comparative concept for infectious diseases rather than a mature application. This review uniquely integrates CRISPR-based diagnostics, therapeutics, and vaccine development within a single infectious disease framework, critically assesses their current maturity, and systematically highlights technical, regulatory, and ethical barriers alongside realistic future priorities. The review concludes that while CRISPR-Cas holds transformative potential for infectious disease management, significant challenges in delivery efficiency, off-target effects, and ethical regulation must be addressed to ensure safe and equitable clinical translation.

Humans

Immunomodulatory effects of palm-derived tocotrienol-rich fraction in healthy volunteers following influenza vaccination: A randomised clinical trial.

Most studies on vitamin E and immunity have focused on tocopherols, but the tocotrienol-rich fraction (TRF) from palm oil may exert stronger immunomodulatory effects. This study investigated the effect of various TRF doses on the immune response to influenza immunisation in healthy adults. We hypothesized daily supplementation with lower doses of TRF can boost immune response to the influenza vaccine in healthy Individuals. In a double-blind placebo-controlled trial, 150 participants (&#x2265;18 years) were randomised to receive placebo or TRF (50, 100, 200, or 400 mg) daily for 2 months, with vaccination on day 28. Blood samples collected on days 0, 28, and 56 were analyzed for humoral and cellular immunity, antioxidant status, and plasma concentrations of vitamin E. TRF significantly augmented anti-influenza antibody production across all doses, with the 400 mg group exhibiting the highest titers. A selective Th1-type immune response was observed, characterized by significant IFN-&#x3b3; production upon restimulation in all TRF-supplemented groups compared with placebo. Plasma IL-12 was elevated in the highest dose, whereas the amount of EBI3 produced increased across a broader range of doses compared to placebo. TRF supplementation was associated with increased antioxidant enzyme activities and stable malondialdehyde activity. Elevated &#x3b1;-tocopherol concentrations observed, primarily at higher doses. Supplementation with TRF can enhance immune response to influenza immunisation by modulating humoral, Th1 responses and improving antioxidant status. Critically, antibody production increased similarly across all TRF doses, suggesting that lower doses may offer a cost-effective strategy for supporting humoral immunity, while higher doses provide broader immunomodulatory benefits.

Humans

Adherence and efficacy of the 0&#x2009;-&#x2009;7&#x2009;-&#x2009;21-day versus the 0&#x2009;-&#x2009;1&#x2009;-&#x2009;6-month hepatitis B vaccination schedules among people who use drugs: a two-year randomized controlled trial.

BACKGROUND: To compare the adherence and efficacy between the 0&#x2009;-&#x2009;7&#x2009;-&#x2009;21-day and the 0&#x2009;-&#x2009;1&#x2009;-&#x2009;6-month hepatitis B virus (HBV) vaccination schedules among people who use drugs (PWUD) in China. RESEARCH DESIGN AND METHODS: A randomized controlled trial was conducted in 1261 HBV-susceptible PWUD from compulsory isolated detoxification centers (CIDCs) and methadone maintenance treatment (MMT) clinics in Xi'an. A 20&#x2009;&#xb5;g per-dose vaccine was used. HBV surface antibody (anti-HBs), surface antigen, and core antibody were tested at months 7, 15, and 22 after the first dose. RESULTS: Third-dose coverage was significantly higher in the 0&#x2009;-&#x2009;7&#x2009;-&#x2009;21-day group (74.40%) than in the 0&#x2009;-&#x2009;1&#x2009;-&#x2009;6-month group (51.58%, p&#x2009;<&#x2009;0.001), mainly driven by participants from CIDCs (77.75% vs. 45.69%). Anti-HBs positive rates at months 7, 15, and 22 among participants who completed all three doses were significantly higher for the 0&#x2009;-&#x2009;1&#x2009;-&#x2009;6-month schedule (90.71%, 76.82%, and 67.35%) than for the 0&#x2009;-&#x2009;7&#x2009;-&#x2009;21-day schedule (74.23%, 49.40%, and 40.95%; all p&#x2009;<&#x2009;0.001). HBV infection incidence was similar between schedules, but significantly different between vaccinees and non-vaccinees (p&#x2009;=&#x2009;0.018). CONCLUSIONS: The 0&#x2009;-&#x2009;7&#x2009;-&#x2009;21-day schedule substantially enhances three-dose completion in PWUD, but induces a notably weaker anti-HBs response and persistence. Schedules should be selected based on the management models for PWUD and their individual characteristics. CLINICAL TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR1900022403).

Humans

Genome-wide scans reveal candidate genes associated with wing morph differentiation in Tetrix japonica.

Wing dimorphism is an important dispersal-related trait in insects, but its genomic basis remains poorly understood in pygmy grasshoppers. Here, we integrated genome-wide single-nucleotide polymorphism (SNP) analyses, population structure inference, selection scans, and functional annotation to investigate genomic differentiation between long- and short-winged Tetrix japonica. Principal component analysis (PCA), ADMIXTURE, and phylogenetic analyses revealed weak genome-wide separation between morphs, indicating differentiation on a largely shared genetic background. Genome-wide scans based on the fixation index (FST), nucleotide diversity ratios, and Tajima's D, using 50-kb non-overlapping windows and empirical top-5% outlier thresholds, identified multiple candidate regions across seven chromosomes. The broader long- and short-winged candidate sets spanned 9.35&#xa0;Mb and 9.37&#xa0;Mb and directly overlapped 82 and 77 genes, respectively. Candidate genes were associated with signaling/hormone regulation, membrane transport, metabolism, cytoskeletal organization, extracellular matrix structure, and development. Short-winged candidate genes were significantly enriched for ABC-type transporter activity and ATP hydrolysis activity. Because all individuals originated from a single laboratory-maintained population with weak genome-wide structure, these regions should be regarded as candidate loci from a screening-stage analysis that require validation in independent populations and by functional assays, rather than as confirmed targets of selection.

Animals

Who Is the Ideal Candidate for High-Definition Liposuction? A Systematic Review and Meta-Analysis.

BACKGROUND: High-definition liposuction (HDL) enhanced muscular definition by selectively removing superficial subcutaneous fat. Despite its growing popularity and high satisfaction rates, no consensus exists regarding the ideal candidate. This systematic review evaluates demographic factors, patient selection criteria, and complication rates associated with HDL. METHODS: A systematic review and meta-analysis were conducted utilizing PRISMA-P guidelines. PubMed, Cochrane Library, Embase, and Web of Science were searched for studies published within the past 10 years. Seventeen studies met inclusion criteria, comprising 9570 patients. Study designs included randomized controlled trials, cohort studies, and observational analyses reporting demographics, procedural details, and complications. Standardized data extraction was performed. Pooled analyses were conducted for hematoma and seroma, and univariable meta-regression assessed associations between mean age, BMI, and proportion of female patients with complication rates. RESULTS: Mean age was 36.0 years and mean BMI was 25.8&#xa0;kg/m 2 (range: 18 to 66); 55% of patients were female. Selection criteria varied; most studies applied BMI thresholds (&#x2264;30 to 34&#xa0;kg/m 2 ) and excluded poorly controlled diabetes, heavy smoking, and thromboembolic history. The abdomen, flanks, and chest were most treated. Mean fat removal was 4268.8&#xa0;mL, with an average operative time of 235 minutes. Complication rates were low; the pooled incidence of seroma was 7% and hematoma was 1%. Meta-regression showed no significant associations between complications and age, BMI, or sex. Patient satisfaction was high. CONCLUSION: HDL is safe and effective across diverse populations; however, variability in selection criteria and reporting limits evidence-based definitions of ideal candidates. Further prospective studies with standardized reporting are needed.

Humans

Analyzing salinity tolerance in grass carp (Ctenopharyngodon idella): Insights from genome-wide association study and genomic selection.

Grass carp (Ctenopharyngodon idella) is one of the most widely cultured freshwater fish species globally. However, the expansion of its farming scale faces severe limitation owing to freshwater scarcity; therefore, the development of strains with greater salinity tolerance is key for expanding production using brackish water resources. To investigate the genetic basis of salinity tolerance in grass carp, a genome-wide association study (GWAS) was conducted using 200 individuals representing extreme phenotypes, namely salinity-tolerant and salinity-sensitive groups. In total, 17 single nucleotide polymorphisms (SNPs) related to salinity tolerance were detected, which were distributed across 11 chromosomes. Through gene annotation, 38 candidate genes were obtained from these loci. Enrichment analysis revealed these candidate genes are primarily implicated in key biological processes, including osmotic regulation, energy metabolism, and stress responses. Analyses of different SNP densities revealed that the 5&#xa0;K SNP density panel can balance prediction accuracy and computational efficiency. The BayesA model achieved the highest prediction accuracy under the GWAS_Evenly selection strategy, with substantial reductions in mean absolute error and mean square error. This study reveals the genetic mechanisms of salinity tolerance in grass carp, which might be optimized through genomic selection, and provides insights for selectively breeding new varieties with greater salinity tolerance.

Animals

Can host genetics transform the sustainable control of tropical theileriosis? Insights from the Tick-Theileria interface.

Tropical theileriosis, caused by the tick-transmitted apicomplexan parasite Theileria annulata, remains a major constraint on cattle production across North Africa, the Mediterranean basin, the Middle East and South Asia. Current control depends on acaricides, the theilericidal drug buparvaquone and live attenuated schizont vaccines, but acaricide resistance, buparvaquone-resistance mutations and the logistical demands of vaccination are eroding the sustainability of these tools. Host genetics offers a complementary and durable alternative. Indigenous Bos indicus breeds are consistently more resistant to ticks and tolerate T. annulata infection better than exotic Bos taurus cattle, and this advantage has a measurable heritable component. Unlike previous reviews, which treat tick resistance, T. annulata immunobiology and livestock genomic selection as separate subjects, we integrate all three and assess host genetics specifically against the failure modes of current control. We review the tick, parasite and host interface, the evidence for natural resistance, and the genetic and immunological mechanisms involved, including signal-regulatory protein, bovine major histocompatibility complex class II and inflammatory pathway genes. We then assess whether genomic selection, multi-omics, machine learning and gene editing can translate these mechanisms into resistant cattle, and we weigh the biological, economic and infrastructural barriers to implementation. The evidence indicates that host genetics will not replace existing control but could reduce reliance on acaricides and chemotherapy. That contribution remains prospective rather than demonstrated: no resistance marker for T. annulata has yet been validated, prediction accuracies are moderate and transfer poorly between breeds, and no endemic production system has implemented selection for resistance.

Animals

Simultaneous Administration of Human Papillomavirus (HPV) Vaccine With Other Recommended Vaccines Among Adolescents Aged 13-17 years, National Immunization Survey-Teen (NIS-Teen), United States, 2023.

PURPOSE: To investigate the percent of adolescents who receive human papillomavirus (HPV) vaccine with one or more other vaccines recommended for adolescents in a single medical visit. METHODS: Data from the 2023 National Immunization Survey-Teen were analyzed. Timing of receipt of HPV vaccine, tetanus, diphtheria, and acellular pertussis vaccine (Tdap), quadrivalent meningococcal conjugate vaccine (MenACWY), and influenza vaccine was assessed using provider-reported vaccination histories. RESULTS: In 2023, among adolescents aged 13-17 years, 69.5% received HPV vaccine with one or more other vaccines recommended for adolescents in a single medical visit. In addition, 47.8% received specifically HPV vaccine, Tdap, and MenACWY together in a single medical visit. DISCUSSION: The HPV vaccine is commonly given with other vaccines recommended for adolescents in a single medical visit. These findings demonstrate variation in simultaneous vaccination patterns, suggesting that flexibility in the recommended adolescent vaccination schedule allows for different approaches to vaccination across clinical settings and family preferences while maintaining adherence to the recommended schedule.

Humans

Vaccine preferences and their role for vaccine confidence and uptake: a meta-ethnography.

Vaccine confidence and uptake are influenced by individuals' preferences regarding vaccine composition, quality, or administration pathways. However, literature synthesizing available qualitative insights into individuals' vaccine preferences remains limited. We therefore conducted a meta-ethnographic systematic review of the qualitative literature on vaccine preferences to identify opportunities for enhancing vaccine confidence and uptake. We implemented a comprehensive search strategy and screened 5,528 studies across seven research databases published between 2001 and 2023. We identified and synthesized 97 qualitative articles to delineate factors influencing consumers' vaccine preferences. Our findings revealed four primary domains shaping individuals' vaccine preferences: Product, Place, Price, and Promotion. First, individuals' preferences for vaccines often hinge on perceived quality and safety of the product itself, which can, for example, be associated with vaccine brand or origin, especially in the case of novel vaccines. Second, people prioritize convenience in terms of vaccination sites and delivery methods (wanting vaccinations offered at their doorstep or in local peripheral clinics); evidence regarding preferred groups to administer the vaccines was mixed. Third, the price of vaccines and the secondary costs associated with vaccination played a role in uptake considerations. Finally, both the sources of information (such as healthcare workers, community volunteers, and religious authorities) and the methods of promoting vaccine information (including face-to-face consultations during clinic visits and the distribution of leaflets or banners), emerged as crucial factors shaping decision-making processes. Overall findings highlight the importance of addressing multifaceted preferences to enhance vaccine confidence and uptake. By understanding individuals' vaccine preferences, strategic recommendations can be developed to optimize vaccination programs and ensure acceptability and utilization.

Humans

Population-level impact of HPV vaccination: a global systematic review of ecological, cross-sectional, and cohort studies.

BACKGROUND: Human papillomavirus (HPV) causes approximately 4.5% of cancers globally, with the highest burden in low- and middle-income countries (LMICs). Since their introduction in 2006, HPV vaccination programs have led to substantial declines in HPV-related outcomes, although impact varies across settings. RESEARCH DESIGN AND METHODS: We conducted a systematic review to evaluate the population-level impact of HPV vaccination on HPV infection, cervical intraepithelial neoplasia grade 2 or higher (CIN2+), genital warts, invasive cervical cancer (ICC), and oropharyngeal cancer (OPC), and examined the influence of coverage, age at initiation, and vaccine type. The review followed PRISMA 2020. RESULTS: Of 13,549 records screened, 63 were included: 9 assessed HPV infection, 24 on CIN2+, 25 on genital warts, and 7 on ICC. Greatest reductions were observed in settings with at least 70% coverage and early vaccination prior to sexual debut, typically achieved through school-based programs. Reported declines ranged from 58-100% for HPV infection, 30-88% for CIN2+, 60-90% for genital warts, and 70-88% for ICC. CONCLUSIONS: HPV vaccination offers strong protection, especially when delivered early and at high coverage within schools. Expanding access and prioritizing underserved populations are essential to achieving global cancer prevention goals. Limitations include heterogeneity across designs, outcome definitions, and follow-up.

Humans

Promoters and Barriers of Vaccine Hesitancy.

This systematic review explores the psychological antecedents of Vaccine Hesitancy, a significant determinant of vaccination behavior. Following PRISMA guidelines, an extensive search was conducted starting from 1673 papers and resulting in 48 publications from various databases. The review identifies psychological factors, specifically cognitive, personality, experiential, and social factors contributing to hesitancy. Cognitive factors include health literacy, conspiracy beliefs, trust, and perceived risk. Personality traits such as extraversion, openness, and psychological capital impact hesitancy, while psychopathy increases it. Personal experiences, like perceived stress and racial discrimination, indirectly affect hesitancy. Social factors, including social relationships and norms, play a significant role in reducing hesitancy. Tailored interventions addressing these factors can enhance vaccine acceptance.

Humans

Safety and immunogenicity of an mRNA COVID-19 vaccine administered to adults: A phase 2, randomized, active-controlled trial.

We conducted a phase 2, randomized, active-controlled, observer-blind study (NCT05960097) among healthy adults&#x2009;&#x2265;18 y of age who completed a primary COVID-19 mRNA vaccination series, with or without a booster, &#x2265;3&#x2009;months earlier. Participants were randomized (1:1:1:1:1) to either receive an investigational bivalent mRNA COVID-19 vaccine encoding ancestral D614G and Omicron BA.4-5 spike proteins (CV0701 mRNA vaccine) at one of three dose levels, an investigational monovalent mRNA COVID-19 vaccine encoding the Omicron BA.4-5 spike protein (CV0601 mRNA vaccine), or a licensed Original Wuhan/Omicron BA.4-5 bivalent mRNA COVID-19 vaccine. The primary objectives were to evaluate reactogenicity, safety and immunogenicity post-vaccination. Secondary and tertiary objectives were to further evaluate humoral and cell-mediated immunity post-vaccination. In total, 425 participants were vaccinated and 381 were included in the Day 29 per-protocol immunogenicity analysis. Most solicited events were mild to moderate. No vaccine-related serious adverse events or myocarditis/pericarditis cases were reported. For the CV0701 mRNA vaccine, a dose-dependent increase in Day 29 neutralizing titers against ancestral D614G and Omicron BA.4-5 was observed. Neutralizing titers against ancestral D614G and Omicron BA.4-5 declined by Days 91 and 181, but remained above baseline. Similar immune responses were observed for the CV0601 mRNA vaccine. At Day 8, CD4+ T cells (Th1 profile) increased in all study groups and CD8+ T cells increased in all study groups, except the lowest CV0701 dose group. The CV0701 and CV0601 mRNA vaccines elicited robust humoral and cellular immunity with an acceptable safety profile, comparable to a licensed, bivalent mRNA vaccine. Clinical Trial Registration EU CT number: 2023-504596-25-00 ClinicalTrials.gov: NCT05960097.

Humans

Seroefficacy of a 10-valent pneumococcal conjugate vaccine (Pneumosil&#xae;) compared with other pneumococcal conjugate vaccines in children.

BACKGROUND: A new 10-valent pneumococcal conjugate vaccine (PCV10SII) was prequalified by WHO in 2019 for children based on non-inferiority of immunogenicity to PCV13 and PCV10GSK. However, the efficacy of PCV10SII against pneumococcal carriage or disease has not been compared with other PCVs. We compared the risk of seroinfection in PCV10SII with PCV10GSK and PCV13-vaccinated infants. METHODS: Data were available for 716 infants from two randomised trials comparing the immunogenicity of PCV10SII with PCV13 and PCV10GSK. Serotype-specific IgG levels were measured from serum samples collected at four weeks after the primary vaccination series and at the time of booster vaccination. We defined seroinfection as any increase in serotype-specific IgG between post-primary vaccination and the booster dose, indicating likely colonisation, subclinical infection, or disease. We compared the relative risk (RR) of seroinfection between PCVs. RESULTS: There was no difference in the risk of seroinfection between PCV10SII and PCV10GSK for the shared serotypes, but PCV10SII showed better protection against 6A and 19A, not included in PCV10GSK. Compared with PCV13, the risk of seroinfection was 65% lower in PCV10SII for serotype 14 (RR&#xa0;=&#xa0;0.35, 95% CI: 0.22, 0.57), 2.27-fold (95% CI: 1.40, 3.68) and 2.91-fold (95% CI: 1.84, 4.60) higher for 6A and 6B seroinfection, and similar for the remaining serotypes. CONCLUSION: PCV10SII demonstrated comparable seroefficacy as PCV10GSK against colonisation by serotypes common to both and may offer better coverage in countries with high prevalence of 6A and 19A disease. The serotype-specific differences in seroefficacy between PCV10SII and PCV13 should be considered when evaluating cost effectiveness. Funding Gates Foundation (INV-056261_2023).

Humans

Ethiopia missed opportunities for vaccination study: Cluster-randomized evaluation of 5-dose measles vaccine vials and a flexible open-vial policy, 2021-2022.

INTRODUCTION: In 2024, an estimated 95,000 people died from measles globally, largely from suboptimal coverage with the measles-containing vaccine (MCV). Health workers may defer vaccinating eligible children to avoid wasting doses from 10-dose MCV vials, which must be discarded six hours after opening. These missed opportunities for vaccination (MOV) reduce coverage and timeliness. Ethiopia, which provides MCV at 9 and 15&#xa0;months, considered switching to 5-dose vials. METHODS: We conducted a 15-month, randomized controlled trial with a nested cross-sectional design in Ethiopia. Sixty woredas were randomized to: (1) policy-only, instructing health workers to open 10-dose vials for any number of eligible children, with additional stock for increased wastage; (2) 5-dose switch, combining this policy with replacement of 10-dose by 5-dose vials; or (3) control (routine 10-dose practice). Household and health-facility surveys at baseline and endline assessed effects on first-dose (MCV1) and second-dose (MCV2) coverage, MCV1 timeliness, and wastage. Generalized estimating equation models estimated net intervention effects versus control. We also estimated the government cost of a nationwide 5-dose switch. RESULTS: MCV1 coverage was similar between policy-only and control (adjusted risk difference [ARD]&#xa0;=&#xa0;-1%, 95%CI: -17%, 15%), with no significant differences in MCV1 timeliness or MCV2 coverage. In the 5-dose switch group, MCV1 coverage changed little (ARD&#xa0;=&#xa0;1%, 95%CI: -17%, 18%), but timely MCV1 at 9&#xa0;months (ARD&#xa0;=&#xa0;18%, 95%CI: 7%, 28%) and MCV2 coverage (ARD&#xa0;=&#xa0;17%, 95%CI: 1%, 34%) rose significantly, and wastage fell (ARD&#xa0;=&#xa0;-7%, 95%CI: -14%, -1%). By endline, 29% of 5-dose health workers opened vials &#x2265;10 times monthly (none in control); caregivers in both intervention groups reported 11% fewer measles-related MOVs. A nationwide 5-dose switch was estimated to save 17% in procurement cost per fully vaccinated (two-dose) child. CONCLUSIONS: The combined 5-dose intervention improved MCV1 timeliness and MCV2 coverage and reduced wastage, addressing a key operational barrier and potentially supporting measles elimination in Ethiopia.

Humans