Vaccine Composition Research Articles

Protective potential of structural proteins of the SARS-CoV-2 virus in protecting against COVID-19

Introduction. Many different vaccines for the prevention of COVID-19 have received emergency use approval in the shortest possible time. Due to the high rate of variability of the pathogen, in this study we analyzed the variability of the structural proteins of the SARS-CoV-2 virus and compared their protective potential in protecting animals from COVID-19. The aim of the study was to compare the protective potential of the SARS-CoV-2 structural proteins in protecting animals from COVID-19. Materials and methods. The SARS-CoV-2 virus was used in the study. Transgenic mice B6.Cg-Tg(K18-ACE2)2Prlmn/J (F1) were used as model animals. Recombinant adenoviral vectors rAd5-S, rAd5-N, rAd5-M were used for immunization of animals. Various genetic, virological and immunological methods, as well as methods of working with animals, were used in the study. Results. The largest number of amino acid substitutions in the structural proteins of different SARS-CoV-2 variants was detected in glycoprotein S, the smallest — in nucleoprotein N. In the COVID-19 animal model, it was shown that only the use of glycoprotein S as a vaccine antigen allows to form protective immunity that protects 100% of animals from a lethal infection caused by the SARS-CoV-2 virus, while the use of protein N protects 50% of animals from a lethal infection, and protein M does not have a protective potential. Conclusion. The data obtained, as well as the analysis of the epidemiological efficacy of various mRNA and vector vaccines, demonstrate that the use of the SARS-CoV-2 glycoprotein S as an antigen allows to form the highest level of protection. Due to the constant change in circulating variants of the SARS-CoV-2 virus, the decrease in the effectiveness of the vaccines with the original antigen composition against new variants of the virus and the continuing high incidence of COVID-19, it is necessary to continuously monitor the effectiveness of vaccines against new variants of the virus and promptly update the antigen composition of vaccines when a decrease in effectiveness is detected.

Globally approved vaccines for COVID-19: a systematic review.

COVID-19 caused a public health emergency, which instituted a global effort to develop vaccines using different platforms, such as basic types and new-generation vaccines. Considering the importance of vaccination in preventing the severity of infectious diseases and the success in developing and approving vaccines against COVID-19 in record time, it is essential to learn about the characteristics of these vaccines. This study aimed to conduct a structured, systematic review following the PRISMA guideline, to analyze the general characteristics of vaccines approved globally for use against COVID-19. We used the list of approved vaccines available by the WHO as guidance to search for studies in the literature. We searched the terms "SARS-CoV-2 and vaccine and safety and efficacy" in the MEDLINE via PUBMED and Web of Science databases. We conducted the research on both bases, including complete articles published from January 2020 to June 2023. The selection of files occurred between May/2021 and June/2023. Therefore, the paper did not consider articles published after this period or vaccines approved after this moment. This study only included approved vaccines; phase three studies published in English. We found 11 published articles from phase three that met the established criteria. The vaccines included in this study were: Cominarty, mRNA-1273 or Spikevax, Vaxzevria or AZD1222 or Covishield, CoronaVac or PicoVacc, and Ad26.COV2.S, SputnikV or Gam-Covid-Vac, Covaxin, NVX-CoV2373 or Covovax or Nuvaxovid, WIV04 and HB02, CoVLP or Covifenz and Convidecia or Ad5-nCoV. We summarized the main findings of each vaccine, considering the vaccine composition, number of doses, efficacy analyses, and main adverse effects. In general, the vaccines had high efficacy rates and few adverse effects. Efficacy values are important for vaccine approval, but they will not necessarily reflect the real-world impact of vaccination. It was seen that the effectiveness of COV2.S, CoronaVac/PicoVacc, Cominarty, and Covaxin vaccines was lower than the efficacy, whereas, for AZD1222/Vaxzevria/Covishield, the two parameters remained at similar rates. All vaccines evaluated have different compositions, dosages, populations, and study designs. All are effective in at least preventing symptomatic COVID-19, causing mild or moderate adverse effects when present.

Predictive Modeling of Respiratory Virus Evolution: Current Capabilities and Limitations

Modeling of viral evolution trajectories is of primary practical importance when selecting strains to be included in influenza and SARS-CoV-2 vaccines. Regular updating of the vaccine composition has a pronounced effect on their efficacy, which depends, first of all, on the correspondence of the strains selected for inclusion in the vaccine to those that will circulate during the epidemic season. Given the complexity of the choice, which is based on a large amount of experimental data, and the need to make it in advance for early deployment of vaccine production, the development of predictive methods can significantly improve the correspondence of the selected vaccine strains to those circulating in the upcoming epidemic season. The article considers the main approaches to modeling viral evolution, describes their strengths and limitations. The optimal approach is selected for predicting the evolution of influenza viruses circulating in Russia. The results of using this approach with an assessment of its predictive power on retrospective genomic data of the A(H1N1)pdm09 subtype from the EpiFlu GISAID database are presented. A method for assessing the correspondence of the set of the most adapted strains obtained as a result of the predictive model to the strains selected by experts for inclusion in influenza vaccines in the corresponding epidemic seasons is proposed. This approach can be expanded to predict the evolution of other respiratory viruses, including SARS-CoV-2.

A Global Collaborative Comparison of SARS-CoV-2 Antigenicity Across 15 Laboratories.

Setting up a global SARS-CoV-2 surveillance system requires an understanding of how virus isolation and propagation practices, use of animal or human sera, and different neutralisation assay platforms influence assessment of SARS-CoV-2 antigenicity. In this study, with the contribution of 15 independent laboratories across all WHO regions, we carried out a controlled analysis of neutralisation assay platforms using the first WHO International Standard for antibodies to SARS-CoV-2 variants of concern (source: NIBSC). Live virus isolates (source: WHO BioHub or individual labs) or spike plasmids (individual labs) for pseudovirus production were used to perform neutralisation assays using the same serum panels. When comparing fold drops, excellent data consistency was observed across the labs using common reagents, including between pseudovirus and live virus neutralisation assays (RMSD of data from mean fold drop was 0.59). Utilising a Bayesian model, geometric mean titres and assay titre magnitudes (offsets) can describe the data efficiently. Titre magnitudes were seen to vary largely even for labs within the same assay group. We have observed that overall, live Microneutralisation assays tend to have the lowest titres, whereas Pseudovirus Neutralisation have the highest (with a mean difference of 3.2 log2 units between the two). These findings are relevant for laboratory networks, such as the WHO Coronavirus Laboratory Network (CoViNet), that seek to support a global surveillance system for evolution and antigenic characterisation of variants to support monitoring of population immunity and vaccine composition policy.

IAPSM’s Position Paper on Influenza Vaccines for Adult Immunization in India

Influenza causes significant morbidity, hospitalizations, and mortality due to lower respiratory tract infections in India. This paper reviews the current evidence regarding influenza epidemiology, the need for vaccination, immunogenicity, and efficacy of available vaccines and provides recommendations for influenza vaccination for adults by the Indian Association of Preventive and Social Medicine (IAPSM). The risk group among adults includes people with chronic disease, the elderly, immunocompromised individuals, pregnant women, travelers, and healthcare workers. Influenza activity is affected by seasons, humidity, and latitude, leading to variability in influenza peaks in different regions of India. The most effective preventive intervention against influenza is vaccination. Current influenza vaccines have good safety profiles, vaccine efficacy, and acceptable cost-effectiveness. As the virus mutates, the vaccine composition should follow WHO recommendations for the current influenza season. Introducing readily available, conventional, and less expensive trivalent influenza vaccines under the national program can achieve maximum impact on the adult population and potentially prevent future outbreaks and pandemics. IAPSM recommends considering routine use of IIV for all individuals above 60 years, adults with comorbidities, and pregnant women in India. The program managers should consider the pattern of influenza seasonality in a particular region. Influenza surveillance conducted through a structured network of laboratories in India has the potential to provide information about circulating strains, morbidity, and mortality. IAPSM emphasizes conducting community-based studies regarding influenza’s burden, vaccine efficacy, timing of vaccination, and cost-effectiveness among Indian adults to generate evidence.

Home-Based Testing as an Approach to Estimate Influenza Vaccine Effectiveness in South Africa, 2021-2022-A Pilot Study.

Surveillance programmes for influenza and other respiratory pathogens are important to generate vaccine effectiveness (VE) estimates and to inform vaccine composition. We aimed to explore the feasibility and acceptability of home-based testing. In three out of nine provinces in South Africa, we established a self-referral system for individuals aged ≥ 18 years with respiratory symptoms of ≤ 10 days duration. Following consent, swab collection material was delivered to participants who also completed a questionnaire including self-reported vaccination status. Swabs were tested by PCR for influenza, respiratory syncytial virus (RSV) and SARS-CoV-2. A test-negative methodology was used to estimate influenza VE. Of 1456 samples collected between 19 November 2021 and 3 September 2022, 73 (5%) tested positive for influenza, 38 (3%) tested positive for RSV and 394 (27%) for SARS-CoV-2. We subtyped 55% (40/73) of the influenza positive specimens; 16/40 (40%) were influenza A(H1N1)pdm09; 10/40 (25%)A(H3N2)) and all 14/40(35%) influenza B were B/Victoria. Only 20% (279/1451) of participants reported influenza-like illness case definition symptoms of fever and cough. Influenza vaccine coverage was 11% (157/1454). The overall influenza VE was 26% (95% confidence interval: -73%, 69%). Of the completed acceptability questionnaires, 123/127 (97%) participants would make use of the service again; 90% (1306) were recruited via the COVID-19 testing centre (call in, social media, webpage), and 7% (99/1306) through CoughWatchSA. Home-based swabbing was feasible and acceptable. We were able to calculate an influenza VE, although a larger sample size and verification of vaccine status may improve the VE estimates in the future.

Rapid spread of the SARS-CoV-2 Omicron XDR lineage derived from recombination between XBB and BA.2.86 subvariants circulating in Brazil in late 2023.

Recombination plays a crucial role in the evolution of SARS-CoV-2. The Omicron XBB* recombinant lineages are a noteworthy example, as they have been the dominant SARS-CoV-2 variant worldwide in the first half of 2023. Since November 2023, a new recombinant lineage between Omicron subvariants XBB and BA.2.86, designated XDR, has been detected mainly in Brazil. In this study, we reconstructed the spatiotemporal dynamics and estimated the absolute and relative transmissibility of the XDR lineage. The XDR lineage displayed a recombination breakpoint in the ORF1a-coding region, and the most closely related sequences to the 5' and 3' ends of the recombinant correspond to JD.1.1 and JN.1.1 lineages, respectively. The first XDR sequences were detected in November 2023 in the Northeastern Brazilian region, and their prevalence rapidly surged from <1% to 25% by February 2024. The Bayesian phylogeographic analysis supports that the XDR lineage likely emerged in the Northeastern Brazilian region around late October 2023 and rapidly disseminated within and outside Brazilian borders from mid-November onward. The median effective reproductive number of the XDR lineage in Brazil during the initial expansion phase was estimated to be around 1.5, and the average relative instantaneous reproduction numbers of XDR and JN* lineages were estimated to be 1.37 and 1.29 higher than that of co-circulating XBB* lineages. In summary, these findings support that the recombinant lineage XDR arose in the Northeastern Brazilian region in October 2023, shortly after the first detection of JN.1 sequences in the country. In Brazil, the XDR lineage exhibited a higher transmissibility level than its parental XBB.* lineages and is spreading at a rate similar to or slightly faster than the JN.1* lineages.IMPORTANCEThis study highlights the emergence and rapid dissemination of the recombinant SARS-CoV-2 XDR lineage, derived from the Omicron lineages JD.1.1 and JN.1.1. The XDR lineage exhibited equivalent transmissibility to its JN.1* parental lineages and quickly spread across Brazil in late 2023. The findings underscore the critical role of real-time genomic surveillance in detecting novel variants with higher transmission potential. By utilizing phylogenetic and epidemiological methods, this research provides important insights into the molecular dynamics of XDR, which could inform public health responses and vaccine composition updates. The study's significance lies in its ability to document the impact of recombination on viral evolution, offering valuable information to the field of virology and pandemic preparedness.

Molecular diagnostics using the QIAstat-Dx syndromic device for covering avian influenza pandemic preparedness

IntroductionA key factor in influenza pandemic preparedness is the ability to detect zoonotic influenza virus strains as they emerge in humans through spillover events, ideally before human-to-human transmission occurs. DesignIn this study, the utility of the QIAstat-Dx syndromic device for influenza surveillance was evaluated. Bioinformatic analysis was performed on all WHO-recommended influenza Candidate Vaccine Viruses (CVVs), including the common strains recommended for the 2023–2024 influenza vaccine composition in the northern hemisphere, and 16 different H5 highly pathogenic avian influenza virus (HPAIV) and two H9N2 low pathogenic avian influenza virus (LPAIV) strains. For laboratory validation, engineered gene fragments and real HPAIV and LPAIV samples were tested using the QIAstat-Dx Respiratory SARS-CoV-2 Panel. ResultsDuring the bioinformatic screening, common influenza strains were positive including influenza A subtypes, and all H5 HPAIV and LPAIV H9N2 were detected as Influenza A positive without subtype discrimination. In all cases, laboratory validation confirmed all bioinformatic results. ConclusionQIAstat-Dx can detect all tested potentially zoonotic influenza A virus strains, and discriminate them from human sesonal influenza A viruses, ensuring a correct diagnosis. Any tool available for surveillance and pandemic preparedness is essential for a rapid response to reduce healthcare costs and severity of future influenza pandemics.

Warehouse-based, immunopeptidome-guided design of personalised peptide vaccines shows feasibility in clinical trial evaluation in CLL patients.

www.clinicaltrialsregister.eu, identifier NCT02802943.

Safety, Immunogenicity and Protective Activity of a Modified Trivalent Live Attenuated Influenza Vaccine for Combined Protection Against Seasonal Influenza and COVID-19 in Golden Syrian Hamsters.

Influenza viruses and SARS-CoV-2 are currently cocirculating with similar seasonality, and both pathogens are characterized by a high mutational rate which results in reduced vaccine effectiveness and thus requires regular updating of vaccine compositions. Vaccine formulations combining seasonal influenza and SARS-CoV-2 strains can be considered promising and cost-effective tools for protection against both infections. We used a licensed seasonal trivalent live attenuated influenza vaccine (3×LAIV) as a basis for the development of a modified 3×LAIV/CoV-2 vaccine, where H1N1 and H3N2 LAIV strains encoded an immunogenic cassette enriched with conserved T-cell epitopes of SARS-CoV-2, whereas a B/Victoria lineage LAIV strain was unmodified. The trivalent LAIV/CoV-2 composition was compared to the classical 3×LAIV in the golden Syrian hamster model. Animals were intranasally immunized with the mixtures of the vaccine viruses, twice, with a 3-week interval. Immunogenicity was assessed on day 42 of the study, and the protective effect was established by infecting vaccinated hamsters with either influenza H1N1, H3N2 or B viruses or with SARS-CoV-2 strains of the Wuhan, Delta and Omicron lineages. Both the classical 3×LAIV and 3×LAIV/CoV-2 vaccine compositions induced similar levels of serum antibodies specific to all three influenza strains, which resulted in comparable levels of protection against challenge from either influenza strain. Protection against SARS-CoV-2 challenge was more pronounced in the 3×LAIV/CoV-2-immunized hamsters compared to the classical 3×LAIV group. These data were accompanied by the higher magnitude of virus-specific cellular responses detected by ELISPOT in the modified trivalent LAIV group. The modified trivalent live attenuated influenza vaccine encoding the T-cell epitopes of SARS-CoV-2 can be considered a promising tool for combined protection against seasonal influenza and COVID-19.

Evolving antibody response to SARS-CoV-2 antigenic shift from XBB to JN.1.

The continuous evolution of SARS-CoV-2, particularly the emergence of BA.2.86/JN.1 lineage replacing XBB, necessitates re-evaluation of vaccine compositions 1-3. Here, we provide a comprehensive analysis of the humoral immune response to XBB and JN.1 human exposure. We demonstrate the antigenic distinctiveness of XBB and JN.1 lineages in SARS-CoV-2-naive individuals, and JN.1 infection elicits superior plasma neutralization against its subvariants. We highlight KP.3's strong immune evasion and receptor binding capability, supporting its foreseeable prevalence. Extensive analysis of the BCR repertoire, isolating ~2000 RBD-specific antibodies with their targeting epitopes characterized by deep mutational scanning (DMS), underscores the superiority of JN.1-elicited memory B cells 4,5. Class 1 IGHV3-53/3-66-derived neutralizing antibodies (NAbs) contribute majorly within wildtype-reactive NAbs against JN.1. However, KP.2 and KP.3 evade a substantial subset, even those induced by JN.1, advocating for booster updates to KP.2/KP.3. JN.1-induced Omicron-specific antibodies also demonstrate high potency across Omicron. Escape hotspots of these NAbs have already been mutated, resulting in higher immune barrier to escape, considering probable recovery of escaped NAbs. Additionally, the prevalence of IGHV3-53/3-66-derived antibodies, and their capability of competing with all Omicron-specific NAbs suggests their inhibitory role on the activation of Omicron-specific naive B cells, potentially explaining the heavy immune imprinting in mRNA-vaccinated individuals 6-8. These findings delineate the evolving antibody response to Omicron antigenic shift from XBB to JN.1, and highlight the importance of developing JN.1-lineage, especially KP.2/KP.3-based vaccine boosters.

Comparative Analysis of the Neutralizing Capacity of Monovalent and Bivalent Formulations of Betuvax-CoV-2, a Subunit Recombinant COVID-19 Vaccine, Against Various Strains of SARS-CoV-2

SARS-CoV-2, the causal agent of the COVID-19 pandemic, is characterized by rapid evolution, which poses a significant public health challenge. Effective vaccines that provide robust protection, elicit strong immune responses, exhibit favorable safety profiles, and enable cost-effective large-scale production are crucial. The RBD-Fc-based Betuvax-CoV-2 vaccine has previously demonstrated a favorable safety profile and induced a significant anti-SARS-CoV-2 humoral immune response in clinical trials. Due to the rapid evolution and emergence of new SARS-CoV-2 strains, the relevance of bivalent vaccine formulations has increased. Methods: This study compared the neutralizing capacity of monovalent and bivalent vaccine formulations against different SARS-CoV-2 strains detected with a SARS-CoV-2 microneutralization assay (MNT). Findings: The monovalent Wuhan-based vaccine generated neutralizing antibodies against the Wuhan and Omicron BA.2 variants but not the distinct Omicron BQ.1 strain. Conversely, the monovalent BA.2-based vaccine induced neutralizing antibodies against both Omicron strains but not Wuhan. While the bivalent Wuhan and BA.2-based vaccine was effective against strains containing the same antigens, it was insufficient to neutralize the distinctive BQ.1 strain at a small dosage. Interpretation: These findings suggest that the vaccine composition should closely match the circulating SARS-CoV-2 strain to elicit the optimal neutralizing antibody response and include the appropriate dosage. Moreover, this study did not find additional advantages of using the bivalent form over the monovalent form for the vaccination against a single prevailing SARS-CoV-2 strain.

Associations between SARS-CoV-2 Infection or COVID-19 Vaccination and Human Milk Composition: A Multi-Omics Approach

BackgroundThe risk of contracting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) via human milk-feeding is virtually nonexistent. Adverse effects of coronavirus disease 2019 (COVID-19) vaccination for lactating individuals are not different from the general population, and no evidence has been found that their infants exhibit adverse effects. Yet, there remains substantial hesitation among this population globally regarding the safety of these vaccines. ObjectivesHerein, we aimed to determine if compositional changes in milk occur following SARS-CoV-2 infection or COVID-19 vaccination, including any evidence of vaccine components. MethodsAn extensive multiomics approach was taken using a subset of milk samples obtained as part of our broad studies examining the effects on milk of SARS-CoV-2 infection and COVID-19 vaccination. ResultsWe found that compared with unvaccinated individuals, SARS-CoV-2 infection was associated with significant compositional differences in 67 proteins, 385 lipids, and 13 metabolites. In contrast, COVID-19 vaccination was not associated with any changes in lipids or metabolites, although it was associated with changes in 13 or fewer proteins. Compositional changes in milk differed by vaccine. Changes following vaccination were greatest after 1–6 h for the mRNA-based Moderna vaccine (8 changed proteins), 3 d for the mRNA-based Pfizer (4 changed proteins), and adenovirus-based Johnson and Johnson (13 changed proteins) vaccines. Proteins that changed after both natural infection and Johnson and Johnson vaccine were associated mainly with systemic inflammatory responses. In addition, no vaccine components were detected in any milk sample. ConclusionsTogether, our data provide evidence of only minimal changes in milk composition because of COVID-19 vaccination, with much greater changes after natural SARS-CoV-2 infection.

Molecular genetic characteristics of Streptococcus pneumoniae serogroups 15 and 11 representatives circulating in Russia and their relationship with global genetic lineages

Aim of the study. Genetic analysis of Streptococcus pneumoniae serogroups 15 and 11 circulating in Russia according to the following parameters: serotype affiliation; clonal complex (CC); presence of resistance and virulence determinants; relatedness to genetic lineages circulating in the world, and justification of inclusion of the actual serotypes of serogroups 15 and 11 in the future conjugate vaccine composition. Materials and methods. The study included whole genome data of S. pneumoniae serogroups 11 and 15. Results. Genomes of serogroup 15 strains from Russia are represented mainly by serotypes 15B and 15C, the majority of which belong to CC-1025 and CC-1262. CC-1025 is characterized by a more frequent association with invasive diseases. Representatives of CC-1025 and CC-1262 contain virulence determinants unique to these genetic lineages within the studied population of serogroup 15: oligopeptide transporters, fructose-specific PTS system, unique hydrolase variants, additional iron ion transporters, the gene of zinc metalloprotease ZmpC (activating human MMP9). The genomes of serogroup 11 are represented mainly by serotype 11A, the majority belong to CC-62 and CC-1012. The virulence determinants unique to CC-62 (within the studied serogroup 11) include bacteriocins, components of oligopeptide transport, flavin reductase-like protein (adhesin, also protects bacteria from oxidative stress), fucose processing operon, PsaA (adhesin, also a component of the ATP-binding cassette transporter that imports manganese ions). Conclusion. In the Russian Federation, serogroups 15 and 11 are the most common non-vaccine serogroups. No antimicrobial resistance determinants have been identified in the genomes of representatives of these serogroups. For each of the genetic lineages prevalent in Russia and associated with serogroups 15 and 11, unique virulence determinants within the studied serogroup have been identified, which may contribute to the success of these lineages. It is advisable to include serotypes 15B and 11A in vaccines promising for the Russian Federation.

Rational selection of TbpB variants elucidates a bivalent vaccine formulation with broad spectrum coverage against Neisseria gonorrhoeae.

Neisseria gonorrhoeae is the causative agent of gonorrhea, an on-going public health problem due in part to the lack of success with efforts to develop an efficacious vaccine to prevent this sexually transmitted infection. An attractive candidate vaccine antigen because of its essential function and surface exposure, the gonococcal transferrin binding protein B (TbpB) exhibits high levels of antigenic variability which poses a significant obstacle in evoking a broadly protective vaccine composition. Here, we utilize phylogenetic information to rationally select TbpB variants for inclusion into a potential gonococcal vaccine and identify two TbpB variants that when formulated together elicit a highly cross-reactive antibody response in both rabbits and mice against a diverse panel of TbpB variants and clinically relevant gonococcal strains. Further, this formulation performed well in experimental proxies of real-world usage, including eliciting bactericidal activity against 8 diverse gonococcal strains and decreasing the median duration of colonization after vaginal infection in female mice by two heterologous strains of N. gonorrhoeae . Together, these data support the use of a combination of TbpB variants for a broadly protective gonococcal vaccine.

A comprehensive review of influenza B virus, its biological and clinical aspects.

Influenza B virus (IBV) stands as a paradox, often overshadowed by its more notorious counterpart, influenza A virus (IAV). Yet, it remains a captivating and elusive subject of scientific inquiry. Influenza B is important because it causes seasonal flu outbreaks that can lead to severe respiratory illnesses, including bronchitis, pneumonia, and exacerbations of chronic conditions like asthma. Limitations in the influenza B virus's epidemiological, immunological, and etiological evolution must be addressed promptly. This comprehensive review covers evolutionary epidemiology and pathogenesis, host-virus interactions, viral isolation and propagation, advanced molecular detection assays, vaccine composition and no animal reservoir for influenza B virus. Complex viral etiology begins with intranasal transmission of influenza B virus with the release of a segmented RNA genome that attacks host cell machinery for transcription and translation within the nucleus and the release of viral progeny. Influenza B virus prevalence in domesticated and wild canines, sea mammals, and birds is frequent, yet there is no zoonosis. The periodic circulation of influenza B virus indicates a 1-3-year cycle for monophyletic strain replacement within the Victoria strain due to frequent antigenic drift in the HA near the receptor-binding site (RBS), while the antigenic stability of Yamagata viruses portrays a more conservative evolutionary pattern. Additionally, this article outlines contemporary antiviral strategies, including pharmacological interventions and vaccination efforts. This article serves as a resource for researchers, healthcare professionals, and anyone interested in the mysterious nature of the influenza B virus. It provides valuable insights and knowledge essential for comprehending and effectively countering this viral foe, which continues to pose a significant public health threat.

Co-circulation of seasonal influenza A(H1N1)pdm09, A(H3N2) and B/Victoria lineage viruses with further genetic diversification, EU/EEA, 2022/23 influenza season.

BackgroundInfluenza viruses can cause large seasonal epidemics with high healthcare impact and severity as they continually change their virological properties such as genetic makeup over time.AimWe aimed to monitor the characteristics of circulating influenza viruses over the 2022/23 influenza season in the EU/EEA countries. In addition, we wanted to compare how closely the circulating viruses resemble the viral components selected for seasonal influenza vaccines, and whether the circulating viruses had acquired resistance to commonly used antiviral drugs.MethodsWe performed a descriptive analysis of the influenza virus detections and characterisations reported by National Influenza Centres (NIC) from the 30 EU/EEA countries from week 40/2022 to week 39/2023 to The European Surveillance System (TESSy) as part of the Global Influenza Surveillance and Response System (GISRS).ResultsIn the EU/EEA countries, the 2022/23 influenza season was characterised by co-circulation of A(H1N1)pdm09, A(H3N2) and B/Victoria-lineage viruses. The genetic evolution of these viruses continued and clade 6B.1A.5a.2a of A(H1N1)pdm09, 3C.2a1b.2a.2b of A(H3N2) and V1A.3a.2 of B/Victoria viruses dominated. Influenza B/Yamagata-lineage viruses were not reported.DiscussionThe World Health Organization (WHO) vaccine composition recommendation for the northern hemisphere 2023/24 season reflects the European virus evolution, with a change of the A(H1N1)pdm09 component, while keeping the A(H3N2) and B/Victoria-lineage components unchanged.

Implications of Cross-Reactivity and Cross-Protection for Pneumococcal Vaccine Development.

Pneumococcal vaccines are a cornerstone for the prevention of pneumococcal diseases, reducing morbidity and mortality in children and adults worldwide. Pneumococcal vaccine composition is based on the polysaccharide capsule of Streptococcus pneumoniae, which is one of the most important identified contributors to the pathogen's virulence. Similarities in the structural composition of polysaccharides included in licensed pneumococcal vaccines may result in cross-reactivity of immune response against closely related serotypes, including serotypes not included in the vaccine. Therefore, it is important to understand whether cross-reactive antibodies offer clinical protection against pneumococcal disease. This review explores available evidence of cross-reactivity and cross-protection associated with pneumococcal vaccines, the challenges associated with the assessment of cross-reactivity and cross-protection, and implications for vaccine design and development.

A self-amplifying RNA vaccine prevents enterovirus D68 infection and disease in preclinical models.

The recent emergence and rapid response to severe acute respiratory syndrome coronavirus 2 was enabled by prototype pathogen and vaccine platform approaches, driven by the preemptive application of RNA vaccine technology to the related Middle East respiratory syndrome coronavirus. Recently, the National Institutes of Allergy and Infectious Diseases identified nine virus families of concern, eight enveloped virus families and one nonenveloped virus family, for which vaccine generation is a priority. Although RNA vaccines have been described for a variety of enveloped viruses, a roadmap for their use against nonenveloped viruses is lacking. Enterovirus D68 was recently designated a prototype pathogen within the family Picornaviridae of nonenveloped viruses because of its rapid evolution and respiratory route of transmission, coupled with a lack of diverse anti-enterovirus vaccine approaches in development. Here, we describe a proof-of-concept approach using a clinical stage RNA vaccine platform that induced robust enterovirus D68-neutralizing antibody responses in mice and nonhuman primates and prevented upper and lower respiratory tract infections and neurological disease in mice. In addition, we used our platform to rapidly characterize the antigenic diversity within the six genotypes of enterovirus D68, providing the necessary data to inform multivalent vaccine compositions that can elicit optimal breadth of neutralizing responses. These results demonstrate that RNA vaccines can be used as tools in our pandemic-preparedness toolbox for nonenveloped viruses.

Effectiveness of Updated 2023-2024 (Monovalent XBB.1.5) COVID-19 Vaccination Against SARS-CoV-2 Omicron XBB and BA.2.86/JN.1 Lineage Hospitalization and a Comparison of Clinical Severity-IVY Network, 26 Hospitals, October 18, 2023-March 9, 2024.

Assessing variant-specific COVID-19 vaccine effectiveness (VE) and severity can inform public health risk assessments and decisions about vaccine composition. BA.2.86 and its descendants, including JN.1 (referred to collectively as "JN lineages"), emerged in late 2023 and exhibited substantial divergence from co-circulating XBB lineages. We analyzed patients hospitalized with COVID-19-like illness at 26 hospitals in 20 U.S. states admitted October 18, 2023-March 9, 2024. Using a test-negative, case-control design, we estimated effectiveness of an updated 2023-2024 (Monovalent XBB.1.5) COVID-19 vaccine dose against sequence-confirmed XBB and JN lineage hospitalization using logistic regression. Odds of severe outcomes, including intensive care unit (ICU) admission and invasive mechanical ventilation (IMV) or death, were compared for JN versus XBB lineage hospitalizations using logistic regression. 585 case-patients with XBB lineages, 397 case-patients with JN lineages, and 4,580 control-patients were included. VE in the first 7-89 days after receipt of an updated dose was 54.2% (95% CI = 36.1%-67.1%) against XBB lineage hospitalization and 32.7% (95% CI = 1.9%-53.8%) against JN lineage hospitalization. Odds of ICU admission (adjusted odds ratio [aOR] 0.80; 95% CI = 0.46-1.38) and IMV or death (aOR 0.69; 95% CI = 0.34-1.40) were not significantly different among JN compared to XBB lineage hospitalizations. Updated 2023-2024 COVID-19 vaccination provided protection against both XBB and JN lineage hospitalization, but protection against the latter may be attenuated by immune escape. Clinical severity of JN lineage hospitalizations was not higher relative to XBB.