Efficacy and Safety of a Bivalent RSV Prefusion F Vaccine in Older Adults

Economic burden of respiratory syncytial virus in adults in Germany - a health claims analysis between 2015 and 2018

AIMS

Respiratory syncytial virus (RSV) causes severe lower respiratory tract infections (LRTI) in infants and adults. While the clinical burden was recently estimated in adults in Germany, little is known about the economic burden yet. To fill this gap, we aimed to assess hospital and outpatient healthcare resource utilization (HRU) and costs of RSV infections in adults in Germany.

METHODS

In this retrospective, observational study on nationwide, representative, anonymized claims data (2015-2018), we identified patients ≥18 years with ICD-10-GM-codes specific to RSV ('RSV-specific'). To increase sensitivity, patients with unspecified LRTIs (including unspecified bronchitis, bronchiolitis, bronchopneumonia, and pneumonia) during RSV seasons were also included as cases potentially caused by RSV ('RSV-possible'). RSV-related HRU (hospital days, ICU and ventilation treatment, drug dispensation) and direct costs were estimated per episode. Excess costs per episode and for follow-up periods were compared to a matched control cohort. All outcomes were reported per healthcare sector and stratified by age and risk groups as well as disease severity (ICU admission/ventilation).

RESULTS

Direct inpatient and outpatient mean episode costs were 3,473€and 82€, respectively, with substantially higher costs for severe cases requiring intensive care and/or ventilation (10,801€). Direct costs for RSV-specific cases were higher than for RSV-possible cases (inpatients: 6,247€vs. 3,450€; outpatients: 127€vs. 82€). Moreover, costs were significantly higher for RSV patients than for controls and increased over time (inpatients: 5,140€per episode vs 10,093€per year; outpatients: 46€per quarter vs 114€per year).

LIMITATIONS

While the number of RSV-specific cases was low, inclusion of seasonal LRTI cases likely increased the sensitivity to detect RSV cases and allowed a better estimation total costs of RSV.

CONCLUSIONS

The economic burden of RSV-LRTI in adults in Germany is substantial, persists long-term and is particularly high in the elderly. This highlights the need for cost-effective prevention measures.

Differences Between RSV A and RSV B Subgroups and Implications for Pharmaceutical Preventive Measures

INTRODUCTION

Understanding the differences between respiratory syncytial virus (RSV) subgroups A and B provides insights for the development of prevention strategies and public health interventions. We aimed to describe the structural differences of RSV subgroups, their epidemiology, and genomic diversity. The associated immune response and differences in clinical severity were also investigated.

METHODS

A literature review from PubMed and Google Scholar (1985-2023) was performed and extended using snowballing from references in captured publications.

RESULTS

RSV has two major antigenic subgroups, A and B, defined by the G glycoprotein. The RSV F fusion glycoprotein in the prefusion conformation is a major target of virus neutralizing antibodies and differs in surface exposed regions between RSV A and RSV B. The subgroups co-circulate annually, but there is considerable debate as to whether clinical severity is impacted by the subgroup of the infecting RSV strain. Large variations between the studies reporting RSV subgroup impact on clinical severity were observed. A tendency for higher disease severity may be attributed to RSV A but no consensus could be reached as to whether infection by one of the subgroup caused more severe outcomes. RSV genotype diversity decreased over the last two decades, and ON and BA have become the sole lineages detected for RSV A and RSV B, since 2014. No studies with data obtained after 2014 reported a difference in disease severity between the two subgroups. RSV F is relatively well conserved and highly similar between RSV A and B, but changes in the amino acid sequence have been observed. Some of these changes led to differences in F antigenic sites compared to reference F sequences (e.g., RSV/A Long strain), which are more pronounced in antigenic sites of the prefusion conformation of RSV B. Initial results from the second season after vaccination suggest specific RSV B efficacy wanes more rapidly than RSV A for RSV PreF-based monovalent vaccines.

CONCLUSIONS

RSV A and RSV B both contribute substantially to the global RSV burden. Both RSV subgroups cause severe disease and none of the available evidence to date suggests any differences in clinical severity between the subgroups. Therefore, it is important to implement measures effective at preventing disease due to both RSV A and RSV B to ensure impactful public health interventions. Monitoring overtime will be needed to assess the impact of waning antibody levels on subgroup-specific efficacy.

Patients With Inflammatory Bowel Disease Are at Increased Risk of Hospitalization Due to Respiratory Syncytial Virus

INTRODUCTION

Patients with inflammatory bowel disease (IBD) are at increased risk of developing respiratory infections. Respiratory syncytial virus (RSV) is a common respiratory virus with adverse outcomes in older adults. This study aimed to determine whether patients with IBD are at increased risk of a serious infection due to RSV.

METHODS

We conducted a retrospective study using the multi-institutional research network TriNetX to assess the risk of hospitalization in a cohort of patients with IBD compared with that in a non-IBD control cohort with RSV infection from January 1, 2007, to February 27, 2023. One-to-one (1:1) propensity score matching was performed for demographic variables and RSV risk factors between the 2 cohorts. Risk was expressed as adjusted odds ratio (aOR) with 95% confidence interval (CI).

RESULTS

There were 794 patients in the IBD-RSV cohort and 93,074 patients in the non-IBD-RSV cohort. The mean age of the IBD-RSV cohort was 55.6 ± 20 years, 59% were female, 80% were White, and 56.9% had Crohn's disease. The IBD-RSV cohort was at an increased risk of hospitalization (aOR 1.30, 95% CI 1.06-1.59). There was no difference in the risk (aOR 0.83, 95% CI 0.58-1.19) of a composite outcome of hospitalization-related complications between the 2 cohorts. Recent systemic corticosteroid use (<3 months) was associated with an increased risk of hospitalization (aOR 1.86, 95% CI 1.30-2.59) in the IBD-RSV cohort.

DISCUSSION

We found that adult patients with IBD and RSV infection are at an increased risk of hospitalization and may benefit from the new RSV vaccine recommended for adults aged 60 years and older.

Altered epidemiological patterns of Respiratory Syncytial Virus and influenza detections in a tropical Australian setting 2020 to 2023

BACKGROUND

We describe the recent temporal patterns of respiratory syncytial virus (RSV) and influenza virus detections in the Northern Territory (NT) of Australia, between 2020 and 2023.

METHODS

This retrospective analysis of patients presenting with respiratory diseases utilised a multiplex viral nucleic acid detection assay for RSV, influenza and SARS Cov2 (COVID-19) to determine the relative frequency of non-COVID-19 respiratory viral detections by age and month during the study period.

RESULTS

During this period of the NT COVID-19 epidemic, disruption of the usual annual wet season RSV outbreak patterns occurred, and the yearly influenza peak was absent for two annual cycles. Our data also reveals that 25% of RSV infections were occurring in patients greater than 40 years of age, compared to 32% of influenza infections presenting in the same period, documenting a greater burden of adult disease than previously documented in the NT.

CONCLUSIONS

Loss of non-COVID-19 viral seasonality and a substantial unrecognised RSV adult burden were noted. We will continue to monitor seasonality, and the RSV burden and this will help to target the populations benefiting from recently released RSV vaccine.

RSV Risk Profile in Hospitalized Adults and Comparison with Influenza and COVID-19 Controls in Valladolid, Spain, 2010-2022

INTRODUCTION

We aimed to describe the risk profile of respiratory syncytial virus (RSV) infections among adults ≥ 60 years in Valladolid from January 2010 to August 2022, and to compare them with influenza and COVID-19 controls.

METHODS

This was a retrospective cohort study of all laboratory-confirmed RSV infections identified in centralized microbiology database during a 12-year period. We analyzed risk factors for RSV hospitalization and severity (length of stay, intensive care unit admission, in-hospital death or readmission < 30 days) and compared severity between RSV patients vs. influenza and COVID-19 controls using multivariable logistic regression models.

RESULTS

We included 706 RSV patients (635 inpatients and 71 outpatients), and 598 influenza and 60 COVID-19 hospitalized controls with comparable sociodemographic profile. Among RSV patients, 96 (15%) had a subtype identified: 56% A, 42% B, and 2% A + B. Eighty-one percent of RSV patients had cardiovascular conditions, 65% endocrine/metabolic, 46% chronic lung, and 43% immunocompromising conditions. Thirty-six percent were coinfected (vs. 21% influenza and 20% COVID-19; p =  < .0001 and 0.01). Ninety-two percent had signs of lower respiratory infection (vs. 85% influenza and 72% COVID-19, p =  < .0001) and 27% cardiovascular signs (vs. 20% influenza and 8% COVID-19, p = 0.0031 and 0.0009). Laboratory parameters of anemia, inflammation, and hypoxemia were highest in RSV. Among RSV, being a previous smoker (adjusted OR 2.81 [95% CI 1.01, 7.82]), coinfection (4.34 [2.02, 9.34]), and having cardiovascular (3.79 [2.17, 6.62]), neurologic (2.20 [1.09, 4.46]), or chronic lung (1.93 [1.11, 3.38]) diseases were risks for hospitalization. Being resident in care institutions (1.68 [1.09, 2.61]) or having a coinfection (1.91[1.36, 2.69]) were risks for higher severity, while RSV subtype was not associated with severity. Whereas RSV and influenza patients did not show differences in severity, RSV patients had 68% (38-84%) lower odds of experiencing any severe outcome compared to COVID-19.

CONCLUSIONS

RSV especially affects those with comorbidities, coinfections, and living in care institutions. RSV vaccination could have an important public health impact in this population.

The Central Conserved Peptides of Respiratory Syncytial Virus G Protein Enhance the Immune Response to the RSV F Protein in an Adenovirus Vector Vaccine Candidate

Respiratory syncytial virus (RSV) is a serious human respiratory pathogen that commonly affects children, older adults, and immunocompromised individuals. At present, the design of licensed vaccines focuses on the incorporation of the pre-fusion protein (PreF protein) of RSV, as this protein has the ability to induce antibodies that offer a high level of protection. Moreover, the G protein contains the CX3C motif that binds the chemokine receptor CX3CR1 in respiratory epithelial cells, which plays an essential role in viral infection. Therefore, incorporating the G antigen into vaccine design may prove more advantageous for RSV prevention. In this study, we developed a human adenoviral vector-based RSV vaccine containing highly neutralizing immunogens, a modified full-length PreF protein fused with the central conserved peptides of the G protein (Gcc) from both RSV subgroups trimerized via a C-terminal foldon, and evaluated its immune response in mice through intranasal (i.n.) immunization. Our results showed that immunization with Ad5-PreF-Qa-Gcc elicited a balanced Th1/Th2 immune response and robust mucosal immunity with higher neutralizing antibody titers against RSV Long and RSV B1. Importantly, immunization with Ad5-PreF-Qa-Gcc enhanced CD4+ CD25+ FoxP3+ Treg cell response and protected the mice against RSV infection. Our data demonstrate that the combination of Gcc and the PreF antigen is a viable strategy for developing effective RSV vaccines.

Inhibiting retinoic acid signaling in dendritic cells suppresses respiratory syncytial virus infection through enhanced antiviral immunity

Retinoic acid (RA), controls the immunoregulatory functions of many immune cells, including dendritic cells (DCs), and is important for mucosal immunity. In DCs, RA regulates the expression of pattern recognition receptors and stimulates interferon production. Here, we investigated the role of RA in DCs in mounting immunity to respiratory syncytial virus (RSV). To abolish RA signaling in DCs, we used mice expressing a dominant negative form of retinoic acid receptor-α (RARα) under the CD11c promoter (CD11c-dnRARα). Paradoxically, upon RSV challenge, these animals had lower viral burden, reduced pathology, and greater Th1 polarized immunity than wild-type (WT) mice. Moreover, CD11c-dnRARα DCs infected with RSV showed enhancement in innate and adaptive immunity genes, while genes associated with viral replication were downregulated. These findings suggest that the absence of RA signaling in DCs enhances innate immunity against RSV infection leading to decreased viral load and reduced pathogenicity.

Occurrence of Central Nervous System Complications of Respiratory Syncytial Virus Infections: A Systematic Review with Meta-Analysis

An increasing base of evidence suggests that respiratory syncytial virus (RSV) infections may be associated with neurological complications. In accord with the PRISMA statement, we performed a systematic review and meta-analysis on the occurrence of encephalitis and encephalopathy associated with documented RSV infections. PubMed, Embase, and Scopus databases were searched for eligible observational studies published up to 10 April 2024. Raw data included the occurrence of RSV infections among cases of encephalitis and/or encephalopathy and cases of encephalitis and/or encephalopathy among series of RSV infections. Data were pooled in a random effects model. Case reports were also collected, and their data pooled as a cumulative series. Heterogeneity was assessed using the I2 measure, while reporting bias was assessed by means of funnel plots and regression analysis. A total of 15 studies for a total of 7719 RSV infections and 1631 cases of encephalitis were analyzed. Moreover, 27 case reports and case series were retrieved, for a total of 84 individual cases of encephalitis/encephalopathy occurring during a documented RSV infection. A pooled prevalence of 2.20 cases of encephalitis/encephalopathy per 100 RSV cases (I2 = 99%) was calculated, while a prevalence of RSV infections among cases of encephalitis/encephalopathy was estimated to 3.53 per 100 cases for studies on respiratory specimens (I2 = 48%) and 0.37 per cases on central nervous system (CNS) specimens (I2 = 0%). Detection of RSV within the CNS was relatively rare (17.86% of pooled case reports), being associated with male gender (adjusted odds ratio [aOR] 5.021, 95% confidence interval [95%CI] 1.104 to 22.831) and recovery with long-term sequelae (aOR 5.699, 95%CI 1.152; 28.183). Case fatality ratio was estimated to be 0.43 per 100 cases on observational studies and 10.71% in case reports, a difference likely due to publication bias. In summary, RSV represented a not frequent but notable cause of encephalitis/encephalopathy in adults and children. The paucity of available studies not only recommends a cautious appraisal of our results but stresses the clinical significance of future studies on incident cases of encephalitis and/or encephalopathy.

Discovery of GS-7682, a Novel 4'-Cyano-Modified C-Nucleoside Prodrug with Broad Activity against Pneumo- and Picornaviruses and Efficacy in RSV-Infected African Green Monkeys

Acute respiratory viral infections, such as pneumovirus and respiratory picornavirus infections, exacerbate disease in COPD and asthma patients. A research program targeting respiratory syncytial virus (RSV) led to the discovery of GS-7682 (1), a novel phosphoramidate prodrug of a 4'-CN-4-aza-7,9-dideazaadenosine C-nucleoside GS-646089 (2) with broad antiviral activity against RSV (EC50 = 3-46 nM), human metapneumovirus (EC50 = 210 nM), human rhinovirus (EC50 = 54-61 nM), and enterovirus (EC50 = 83-90 nM). Prodrug optimization for cellular potency and lung cell metabolism identified 5'-methyl [(S)-hydroxy(phenoxy)phosphoryl]-l-alaninate in combination with 2',3'-diisobutyrate promoieties as being optimal for high levels of intracellular triphosphate formation in vitro and in vivo. 1 demonstrated significant reductions of viral loads in the lower respiratory tract of RSV-infected African green monkeys when administered once daily via intratracheal nebulized aerosol. Together, these findings support additional evaluation of 1 and its analogues as potential therapeutics for pneumo- and picornaviruses.

Identification of distinct genotypes in circulating RSV A strains based on variants in the virus replication-associated genes

Respiratory syncytial virus (RSV) is a common cause of respiratory infection that often leads to hospitalization of infected younger children and older adults. RSV is classified into two strains, A and B, each with several subgroups or genotypes. One issue with the definition of these subgroups is the lack of a unified method of identification or genotyping. We propose that genotyping strategies based on the genes coding for replication-associated proteins could provide critical information on the replication capacity of the distinct subgroups, while clearly distinguishing genotypes. Here, we analyzed the virus replication-associated genes N, P, M2, and L from de novo assembled RSV A sequences obtained from 31 newly sequenced samples from hospitalized patients in Philadelphia and 78 additional publicly available sequences from different geographic locations within the United States. In-depth analysis and annotation of variants in the replication-associated proteins identified the polymerase protein L as a robust target for genotyping RSV subgroups. Importantly, our analysis revealed non-synonymous variations in L that were consistently accompanied by conserved changes in its co-factor P or the M2-2 protein, suggesting associations and interactions between specific domains of these proteins. Similar associations were seen among sequences of the related human metapneumovirus. These results highlight L as an alternative to other RSV genotyping targets and demonstrate the value of in-depth analyses and annotations of RSV sequences as it can serve as a foundation for subsequent in vitro and clinical studies on the efficiency of the polymerase and fitness of different virus isolates.IMPORTANCEGiven the historical heterogeneity of respiratory syncytial virus (RSV) and the disease it causes, there is a need to understand the properties of the circulating RSV strains each season. This information would benefit from an informative and consensus method of genotyping the virus. Here, we carried out a variant analysis that shows a pattern of specific variations among the replication-associated genes of RSV A across different seasons. Interestingly, these variation patterns, which were also seen in human metapneumovirus sequences, point to previously defined interactions of domains within these genes, suggesting co-variation in the replication-associated genes. Our results also suggest a genotyping strategy that can prove to be particularly important in understanding the genotype-phenotype correlation in the era of RSV vaccination, where selective pressure on the virus to evolve is anticipated. More importantly, the categorization of pneumoviruses based on these patterns may be of prognostic value.

Assembly of respiratory syncytial virus matrix protein lattice and its coordination with fusion glycoprotein trimers

Respiratory syncytial virus (RSV) is an enveloped, filamentous, negative-strand RNA virus that causes significant respiratory illness worldwide. RSV vaccines are available, however there is still significant need for research to support the development of vaccines and therapeutics against RSV and related Mononegavirales viruses. Individual virions vary in size, with an average diameter of ~130 nm and ranging from ~500 nm to over 10 µm in length. Though the general arrangement of structural proteins in virions is known, we use cryo-electron tomography and sub-tomogram averaging to determine the molecular organization of RSV structural proteins. We show that the peripheral membrane-associated RSV matrix (M) protein is arranged in a packed helical-like lattice of M-dimers. We report that RSV F glycoprotein is frequently observed as pairs of trimers oriented in an anti-parallel conformation to support potential interactions between trimers. Our sub-tomogram averages indicate the positioning of F-trimer pairs is correlated with the underlying M lattice. These results provide insight into RSV virion organization and may aid in the development of RSV vaccines and anti-viral targets.

RSV Prevention Within Reach for Older Infants and Toddlers: The Role of Active Immunization

This review article will summarize the vaccines and monoclonal antibodies currently under evaluation for the prevention of RSV disease in older infants, toddlers and young children. We will review the rationale for passive protection during the first months of life, and the role of active immunization afterwards, either with live attenuated, protein-based or mRNA vaccines.

Exacerbations of bronchiectasis

Bronchiectasis presents a significant challenge due to its rising prevalence, associated economic burden and clinical heterogeneity. This review synthesises contemporary understanding and literature of bronchiectasis exacerbations, addressing the transition from stable state to exacerbations, underlining the importance of early and precise recognition, rigorous severity assessment, prompt treatment, and prevention measures, as well as emphasising the need for strategies to assess and improve early and long-term patient outcomes. The review highlights the interplay between stable state phases and exacerbations in bronchiectasis, introducing the concept of "exogenous and endogenous changes in airways homeostasis" and the "adapted island model" with a particular focus on "frequent exacerbators", a group of patients associated with specific clinical characteristics and worse outcomes. The pathophysiology of exacerbations is explored through the lens of microbial and nonmicrobial triggers and the presence and the activity of comorbidities, elaborating on the impact of both exogenous insults, such as infections and pollution, and endogenous factors such as inflammatory endotypes. Finally, the review proposes a multidisciplinary approach to care, integrating advancements in precision medicine and biomarker research, paving the way for tailored treatments that challenge the traditional antibiotic paradigm.

Therapies to Decrease Severe Respiratory Syncytial Virus Illness

This JAMA Insights discusses the use of monoclonal antibodies or protein-based vaccines to help prevent severe RSV infection in infants, children, and older adults.

Filling two needs with one deed: a combinatory mucosal vaccine against influenza A virus and respiratory syncytial virus

Influenza A Virus (IAV) and Respiratory Syncytial Virus (RSV) are both responsible for millions of severe respiratory tract infections every year worldwide. Effective vaccines able to prevent transmission and severe disease, are important measures to reduce the burden for the global health system. Despite the strong systemic immune responses induced upon current parental immunizations, this vaccination strategy fails to promote a robust mucosal immune response. Here, we investigated the immunogenicity and efficacy of a mucosal adenoviral vector vaccine to tackle both pathogens simultaneously at their entry site. For this purpose, BALB/c mice were immunized intranasally with adenoviral vectors (Ad) encoding the influenza-derived proteins, hemagglutinin (HA) and nucleoprotein (NP), in combination with an Ad encoding for the RSV fusion (F) protein. The mucosal combinatory vaccine induced neutralizing antibodies as well as local IgA responses against both viruses. Moreover, the vaccine elicited pulmonary CD8+ and CD4+ tissue resident memory T cells (TRM) against the immunodominant epitopes of RSV-F and IAV-NP. Furthermore, the addition of Ad-TGFβ or Ad-CCL17 as mucosal adjuvant enhanced the formation of functional CD8+ TRM responses against the conserved IAV-NP. Consequently, the combinatory vaccine not only provided protection against subsequent infections with RSV, but also against heterosubtypic challenges with pH1N1 or H3N2 strains. In conclusion, we present here a potent combinatory vaccine for mucosal applications, which provides protection against two of the most relevant respiratory viruses.

Respiratory Syncytial Virus Vaccination in the Adult Pulmonary Patient

TOPIC IMPORTANCE

Since its discovery in 1957, respiratory syncytial virus (RSV) has been widely recognized as a common and deadly pathogen. Although early studies focused on the impact of RSV on the health of children, more recent data show that RSV imposes a significant burden on individuals aged ≥ 70 years. RSV also substantially harms the health of individuals with cardiopulmonary diseases.

REVIEW FINDINGS

Early efforts to develop an RSV vaccine were hampered by toxicity due to antibody-enhanced viral pneumonia and a lack of efficacy in vaccines that targeted the postfusion configuration of the F fusion protein, which is crucial to the pathogenesis of RSV-mediated injury. A newer wave of vaccines has targeted a stabilized prefusion F protein, generating effective neutralizing antibodies and reducing the burden of mild and severe RSV lower respiratory tract injury. This review focuses on the burden of RSV in patients with pulmonary diseases, highlights the tumultuous path from the early days of RSV vaccine development to the modern era, and offers insights into key gaps in knowledge that must be addressed to adequately protect the vulnerable population of patients with severe pulmonary diseases.

SUMMARY

RSV vaccination with bivalent RSVPreF or RSVPreF3OA, which target the stabilized prefusion F protein, can be broadly recommended to adults with pulmonary diseases aged ≥ 60 years. However, more data are needed to understand how these vaccinations affect key clinical outcomes in individuals with pulmonary disease.

Efficacy and safety of vaccines to prevent respiratory syncytial virus infection in infants and older adults: A systematic review and meta-analysis

OBJECTIVES

To determine the efficacy and safety of respiratory syncytial virus (RSV) vaccines in infants and older adults.

METHODS

We performed a systematic review and meta-analysis of randomized control trials that evaluated the efficacy of maternal RSV immunization against infections in infants, as well as the efficacy of RSV vaccines in older adults. The primary outcome was the vaccine efficacy against RSV-related lower respiratory tract disease (LRTD). Grading of Recommendations Assessment, Development and Evaluation criteria was used to evaluate the level of evidence.

RESULTS

Ten trials were included in the review. For maternal vaccination, the RSV vaccine showed favourable efficacy against RSV-related LRTD (vaccine efficacy 57.3%, 95% confidence interval [CI] 31.3-73.5; low certainty) and RSV-related severe LRTD (vaccine efficacy 81.9%, 95% CI 56.8-92.4; moderate certainty) in infants within 90 days after birth. For older adults, Meta-analysis showed that RSV vaccines could also reduce the risk of RSV-related LRTD (vaccine efficacy 78.3%, 95% CI 65.6-86.3; moderate certainty) and RSV-related severe LRTD (vaccine efficacy 86.5%, 95% CI 68.3-94.3; moderate certainty). There was no significant difference in serious adverse events between RSV vaccines and placebo.

CONCLUSION

RSV vaccines have the potential to offer protection against RSV disease in both infants and older adults, without apparent safety concerns.

Respiratory Syncytial Virus in Adult Patients at a Tertiary Care Hospital in Germany: Clinical Features and Molecular Epidemiology of the Fusion Protein in the Severe Respiratory Season of 2022/2023

Following an interseasonal rise in mainly pediatric respiratory syncytial virus (RSV) cases in Germany in 2021, an exceptionally high number of adult cases was observed in the subsequent respiratory season of 2022/2023. The aim of this study was to compare the clinical presentation of RSV infections in the pre- and post-SARS-CoV-2 pandemic periods. Additionally, the local epidemiology of the RSV fusion protein was analyzed at a molecular genetic and amino acid level. RSV detections in adults peaked in calendar week 1 of 2023, 8 weeks earlier than the earliest peak observed in the three pre-pandemic seasons. Although the median age of the adult patients was not different (66.5 vs. 65 years), subtle differences between both periods regarding comorbidities and the clinical presentation of RSV cases were noted. High rates of comorbidities prevailed; however, significantly lower numbers of patients with a history of lung transplantation (p = 0.009), chronic kidney disease (p = 0.013), and immunosuppression (p = 0.038) were observed in the 2022/2023 season. In contrast, significantly more lower respiratory tract infections (p < 0.001), in particular in the form of pneumonia (p = 0.015) and exacerbations of obstructive lung diseases (p = 0.008), were detected. An ICU admission was noted for 23.7% of all patients throughout the study period. Sequence analysis of the fusion protein gene revealed a close phylogenetic relatedness, regardless of the season of origin. However, especially for RSV-B, an accumulation of amino acid point substitutions was noted, including in antigenic site Ø. The SARS-CoV-2 pandemic had a tremendous impact on the seasonality of RSV, and the introduction of new vaccination and immunization strategies against RSV warrants further epidemiologic studies of this important pathogen.

Development and Validation of an Enzyme-Linked Immunosorbent Assay-Based Protocol for Evaluation of Respiratory Syncytial Virus Vaccines

Recently, respiratory syncytial virus (RSV) vaccines based on the prefusion F (pre-F) antigen were approved in the United States. We aimed to develop an enzyme-linked immunosorbent assay (ELISA)-based protocol for the practical and large-scale evaluation of RSV vaccines. Two modified pre-F proteins (DS-Cav1 and SC-TM) were produced by genetic recombination and replication using an adenoviral vector. The protocol was established by optimizing the concentrations of the coating antigen (pre-F proteins), secondary antibodies, and blocking buffer. To validate the protocol, we examined its accuracy, precision, and specificity using serum samples from 150 participants across various age groups and the standard serum provided by the National Institute of Health. In the linear correlation analysis, coating concentrations of 5 and 2.5 μg/mL of DS-Cav1 and SC-TM showed high coefficients of determination (r > 0.90), respectively. Concentrations of secondary antibodies (alkaline phosphatase-conjugated anti-human immunoglobulin G, diluted 1:2000) and blocking reagents (5% skim milk/PBS-T) were optimized to minimize non-specific reactions. High accuracy was observed for DS-Cav1 (r = 0.90) and SC-TM (r = 0.86). Further, both antigens showed high precision (coefficient of variation < 15%). Inhibition ELISA revealed cross-reactivity of antibodies against DS-Cav1 and SC-TM, but not with the attachment (G) protein.

Assessing the Real-World Effectiveness of Immunizations for Respiratory Syncytial Virus

This Viewpoint discusses recommendations from the US Centers for Disease Control and Prevention for newly licensed immunizations for respiratory syncytial virus in infants, children with high-risk conditions, and older adults.

Updates on respiratory syncytial virus prophylaxis: the past, present and future

PURPOSE OF REVIEW

Human respiratory syncytial virus (RSV) causes acute respiratory infection in individuals of all age groups. It is the most common pathogen identified in infants and young children with acute lower respiratory infection. Although most infants and young children experience mild, cold-like symptoms, some infants develop severe lower respiratory tract disease such as pneumonia and bronchiolitis that may result in an emergency department visit or hospitalization.

RECENT FINDINGS

In the United States, hospitalization rates have risen during the last decades, and while premature infants with chronic lung disease and congenital heart disease are at increased risk for severe presentations, the majority of hospitalizations occur in previously healthy infants. Until recently, RSV prophylaxis was only available for former preterm infants and those with certain underlying medical conditions.

SUMMARY

The need for preventive interventions against RSV is crucial. This paper will provide a review of the vaccine development, the spectrum of RSV prophylaxis, current challenges associated with the cost, insurance coverage and equitable distribution of targeted therapies.

Evolving Epidemiology of Pediatric Respiratory Syncytial Virus (RSV) Cases Around COVID-19 Pandemic: Impact and Clinical Insights, Retrospective Cohort Study

BACKGROUND

The burden of respiratory syncytial virus (RSV) in high-risk pediatric patients remains unclear. Therefore, this study aims to characterize pediatric RSV cases from January 2019 to December 2022 and assess the impact of the COVID-19 pandemic on RSV burden and RSV-related outcomes. In addition, examining factors influencing RSV-related hospitalization.

METHODS

This is a retrospective study that included pediatric patients (aged 14 and below) who presented at King Faisal Specialist Hospital and Research Centre (KFSHRC) in Riyadh, Saudi Arabia with RSV infection identified using real-time reverse-transcriptase polymerase chain reaction assays. Statistical analyses were performed using STATA.

RESULTS

A total of 885 RSV cases were reported; (56.05%) were males and (43.95%) were females with a median age of 24 months [interquartile range (IQR): 11-60]. 534 (60.34%) required hospitalization. As for RSV seasonality, there was a significant increase in RSV prevalence following the COVID-19 pandemic, escalating from 205 cases in 2019 to 425 cases in 2022. The increase in 2022 was evident in January and persisted from September to December, reaching its peak during the months of October (20.70% - 88 cases) and November (32.00% - 136 cases). About (27.12%) of RSV infected children were medically free patients. Symptomatic patients exhibited various clinical manifestations, with ventilation necessary in (13.11%) of cases. Further analysis revealed significant changes in RSV-related outcomes post-COVID-19, including a decrease in hospitalization rates, an increase in medically free patients, and a lower need for ventilation (p < 0.05). Notably, a significant proportion of RSV admissions occurred within the first 6 months of life, with (77.69%) in the age group of 0 to 5 months. In addition, previous RSV infection, prematurity, low birth weight, renal disease, congenital heart disease, endocrine/metabolic disease, neuro/neuromuscular diseases, and genetic disorders were positively associated with hospitalization (P < 0.05). Interestingly, asthma and bone marrow transplantation were negatively associated with hospitalization (P < 0.05). The mortality rate in this study is (2.37%) (21/885).

CONCLUSION

This study provides a comprehensive understanding of the demographic and clinical factors influencing RSV outcomes, highlighting the impact of the COVID-19 pandemic and shedding light on potential risk factors for RSV-related hospitalization. The highest prevalence of RSV during (September to January), aligning with global patterns and emphasizing the importance of timing in preventive strategies.

Novel drugs approved by the EMA, the FDA, and the MHRA in 2023: A year in review

In 2023, seventy novel drugs received market authorization for the first time in either Europe (by the EMA and the MHRA) or in the United States (by the FDA). Confirming a steady recent trend, more than half of these drugs target rare diseases or intractable forms of cancer. Thirty drugs are categorized as "first-in-class" (FIC), illustrating the quality of research and innovation that drives new chemical entity discovery and development. We succinctly describe the mechanism of action of most of these FIC drugs and discuss the therapeutic areas covered, as well as the chemical category to which these drugs belong. The 2023 novel drug list also demonstrates an unabated emphasis on polypeptides (recombinant proteins and antibodies), Advanced Therapy Medicinal Products (gene and cell therapies) and RNA therapeutics, including the first-ever approval of a CRISPR-Cas9-based gene-editing cell therapy.

Respiratory Syncytial Virus Infection in Older Adults: An Update

Respiratory syncytial virus (RSV) infection represents one of the most common infections during childhood, with significant morbidity and mortality in newborns and in the early years of life. RSV is a common infection throughout all age groups, largely undetected and underestimated in adults, with a disproportionately high impact in older individuals. RSV infection has a wide range of clinical presentations, from asymptomatic conditions to acute pneumonia and severe life-threatening respiratory distress, including exacerbations of underlying chronic conditions. Overall, the incidence of RSV infections requiring medical attention increases with age, and it is highest among persons ≥ 70 years of age. As a consequence of a combination of an aging population, immunosenescence, and the related increased burden of comorbidities, high-income countries are at risk of developing RSV epidemics. The standard of care for RSV-infected patients remains supportive, including fluids, antipyretics, and oxygen support when needed. There is an urgent need for antivirals and preventive strategies in this population, particularly in individuals at higher risk of severe outcomes following RSV infection. In this review, we describe prevention and treatment strategies for RSV illnesses, with a deep focus on the novel data on vaccination that has become available (Arexvy, GSK, and Abrysvo, Pfizer) for older adults.

Parent's perception of respiratory syncytial virus and subsequent wheezing burden: A multi-country cross-sectional survey

BACKGROUND

Respiratory Syncytial Virus (RSV) is the leading cause of hospitalization in infants. RSV bronchiolitis is associated with an increased risk of subsequent wheezing. We aimed to document the parents' perception of the link between RSV infection and subsequent wheezing, wheezing-related healthcare and family resources use, and its impact on family daily life.

METHODS

This cross-sectional online survey enrolled 1200 parents with at least one child ≤6y living in the United States, United Kingdom, Spain, and Italy. Children diagnosed with RSV bronchiolitis before age of 2 years were included in the RSV group, and those never diagnosed with RSV bronchiolitis in the Reference group.

RESULTS

The odds of wheezing were 4.5-fold (95%CI 3.5-5.9) higher in the RSV than in the Reference group. The odds increased to 7.7-fold (95%CI 5.4-11.1) among children who were hospitalized, and 9-fold (95%CI 5.1-16.6) among those admitted to pediatric intensive care with RSV bronchiolitis. Similar trends were observed across all countries. In total, 57% of parents reported their child's wheezing to have moderate to severe impact on their emotional well-being, and 53% on their daily life activities and/or social life. 64% of parents reported moderate-severe impact of wheezing on child's quality of sleep and 49% and 46% reported a moderate-severe impact on their children's emotional well-being and physical activities.

CONCLUSIONS

This survey suggests an association between RSV infection and subsequent wheezing in children across different countries. Wheezing, especially in association with RSV infection, was associated with increased healthcare utilization and costs, and significantly impacted parents' and children daily life.

The respiratory syncytial virus vaccines are here: Implications for solid organ transplantation

In 2023, the Food and Drug Administration approved 2 recombinant subunit respiratory syncytial virus (RSV) vaccines based on prefusion RSV F glycoproteins for the prevention of RSV-associated lower respiratory tract disease. These vaccines were subsequently recommended for individuals ≥60 years of age using shared clinical decision-making by the Center for Disease Control and Prevention's Advisory Committee on Immunization Practices. The development, deployment, and uptake of respiratory virus vaccines are of particular importance for solid organ recipients who are at higher risk of infectious complications and poor clinical outcomes, including from RSV-associated lower respiratory tract disease, compared to patients without immunocompromise. This review aims to summarize what is currently known about the burden of RSV disease in solid organ transplantation, to describe the currently available tools to mitigate the risk, and to highlight considerations regarding the implementation of these vaccines before and after transplantation. We also explore areas of unmet need for organ transplant recipients including questions of RSV vaccine effectiveness and safety, inequities in disease and vaccine access based on race and socioeconomic status, and expansion of coverage to immunocompromised individuals below the age of 60 years.

Acute Cardiac Events in Hospitalized Older Adults With Respiratory Syncytial Virus Infection

Importance

Respiratory syncytial virus (RSV) infection can cause severe respiratory illness in older adults. Less is known about the cardiac complications of RSV disease compared with those of influenza and SARS-CoV-2 infection.

Objective

To describe the prevalence and severity of acute cardiac events during hospitalizations among adults aged 50 years or older with RSV infection.

Design, Setting, and Participants

This cross-sectional study analyzed surveillance data from the RSV Hospitalization Surveillance Network, which conducts detailed medical record abstraction among hospitalized patients with RSV infection detected through clinician-directed laboratory testing. Cases of RSV infection in adults aged 50 years or older within 12 states over 5 RSV seasons (annually from 2014-2015 through 2017-2018 and 2022-2023) were examined to estimate the weighted period prevalence and 95% CIs of acute cardiac events.

Exposures

Acute cardiac events, identified by International Classification of Diseases, 9th Revision, Clinical Modification or International Statistical Classification of Diseases, Tenth Revision, Clinical Modification discharge codes, and discharge summary review.

Main Outcomes and Measures

Severe disease outcomes, including intensive care unit (ICU) admission, receipt of invasive mechanical ventilation, or in-hospital death. Adjusted risk ratios (ARR) were calculated to compare severe outcomes among patients with and without acute cardiac events.

Results

The study included 6248 hospitalized adults (median [IQR] age, 72.7 [63.0-82.3] years; 59.6% female; 56.4% with underlying cardiovascular disease) with laboratory-confirmed RSV infection. The weighted estimated prevalence of experiencing a cardiac event was 22.4% (95% CI, 21.0%-23.7%). The weighted estimated prevalence was 15.8% (95% CI, 14.6%-17.0%) for acute heart failure, 7.5% (95% CI, 6.8%-8.3%) for acute ischemic heart disease, 1.3% (95% CI, 1.0%-1.7%) for hypertensive crisis, 1.1% (95% CI, 0.8%-1.4%) for ventricular tachycardia, and 0.6% (95% CI, 0.4%-0.8%) for cardiogenic shock. Adults with underlying cardiovascular disease had a greater risk of experiencing an acute cardiac event relative to those who did not (33.0% vs 8.5%; ARR, 3.51; 95% CI, 2.85-4.32). Among all hospitalized adults with RSV infection, 18.6% required ICU admission and 4.9% died during hospitalization. Compared with patients without an acute cardiac event, those who experienced an acute cardiac event had a greater risk of ICU admission (25.8% vs 16.5%; ARR, 1.54; 95% CI, 1.23-1.93) and in-hospital death (8.1% vs 4.0%; ARR, 1.77; 95% CI, 1.36-2.31).

Conclusions and Relevance

In this cross-sectional study over 5 RSV seasons, nearly one-quarter of hospitalized adults aged 50 years or older with RSV infection experienced an acute cardiac event (most frequently acute heart failure), including 1 in 12 adults (8.5%) with no documented underlying cardiovascular disease. The risk of severe outcomes was nearly twice as high in patients with acute cardiac events compared with patients who did not experience an acute cardiac event. These findings clarify the baseline epidemiology of potential cardiac complications of RSV infection prior to RSV vaccine availability.

How Does the Burden of Respiratory Syncytial Virus Compare to Influenza in Spanish Adults?

BACKGROUND

Respiratory syncytial virus (RSV) and influenza infections cause significant annual morbidity and mortality worldwide in at-risk populations. This study is aimed at assessing hospital burden and healthcare resource utilization (HRU) of RSV and influenza in adults in Spain.

METHODS

Data were obtained from the Projected Hospitalisation Database of inpatient episodes (ages: younger adults 18-50 and 51-64 years; older adults 65-74, 75-84, and ≥ 85 years) during 2015, 2017, and 2018 in Spanish public hospitals. Incidence, mean hospitalization, and HRU assessments, including length of stay (LOS), intensive care unit (ICU) usage, and age-standardized mortality rates, were collected and stratified by age group, with analyses focusing on the adult population (≥ 18 years old).

RESULTS

Mean hospitalization rate in the population across all years was lower in individuals with RSV versus influenza (7.2/100,000 vs. 49.7/100,000 individuals). ICU admissions and median LOS were similar by age group for both viruses. Age-standardized mortality was 6.3/100,000 individuals and 6.1/100,000 individuals in patients with RSV and influenza, respectively, and mortality rates were similar in older adults (≥ 65 years) for both viruses.

CONCLUSIONS

RSV and influenza infection were associated with considerable HRU. There is a substantial disease burden for RSV infection in older adults ≥ 65 years. While RSV hospitalization rates in adults reported here appeared lower than influenza, RSV is still underdiagnosed in the hospital setting and its incidence might be similar to, or higher than, influenza.

RSV Infection in Refugees and Asylum Seekers: A Systematic Review and Meta-Analysis

Respiratory diseases, including respiratory syncytial virus (RSV) infections, are common reasons for seeking healthcare among refugees and asylum seekers. A systematic review with meta-analysis was designed to appraise all the available evidence on RSV infections among individuals in refugee camps. Three medical databases (PubMed, Embase, and Scopus) as well as the preprint repository medRxiv.org were searched for eligible observational studies, and the collected cases were pooled in a random-effects meta-analysis model. Heterogeneity was assessed using the I2 statistics. Funnel plots and a regression analysis were calculated for analyzing reporting bias. Eventually, six studies were retrieved from three areas (Bangladesh, Thailand, and Kenya), with pooled estimates of 129.704 cases per 1000 samples (95% CI 66.393 to 237.986) for RSV compared to 110.287 per 1000 people for influenza A (95% CI 73.186 to 162.889), 136.398 cases per 1000 people (95% CI 84.510 to 212.741) for human adenovirus (HAdV), 69.553 per 1000 people (95% CI 49.802 to 96.343) for parainfluenzavirus (PIFV), and 60.338 per 1000 people (95% CI 31.933 to 111.109) for human metapneumovirus (hMPV). Using influenza A as a reference group, the risk for a positive specimen was greater for RSV (relative risk [RR] 1.514, 95% CI 1.396 to 1.641) and HAdV (RR 1.984, 95% CI 1.834 to 2.146) and lower for influenza B (RR 0.276, 95% CI: 0.239 to 0.319), PIFV (RR: 0.889, 95% CI 0.806 to 0.981), and hMPV (RR 0.594, 95% CI 0.534 to 0.662). In summary, high rates of RSV infections were documented among individuals sheltered in refugee camps, stressing the importance of specifically designed preventive strategies.

Long-term efficacy and immunogenicity of Ad26.RSV.preF-RSV preF protein vaccine (CYPRESS): a randomised, double-blind, placebo-controlled, phase 2b study

BACKGROUND

Ad26.RSV.preF-RSV preF protein showed 80·0% vaccine efficacy against respiratory syncytial virus (RSV) lower respiratory tract disease (LRTD) in older adults during one RSV season. No RSV vaccines have shown three-season efficacy. We aimed to evaluate efficacy of Ad26.RSV.preF-RSV preF protein over three RSV seasons.

METHODS

CYPRESS was a randomised, double-blind, placebo-controlled, phase 2b study done at 40 US clinical research centres wherein adults aged 65 years or older were centrally randomly assigned 1:1 by computer algorithm to receive Ad26.RSV.preF-RSV preF protein or placebo (one intramuscular injection) on day 1. Investigators, participants, site personnel, and the sponsor were masked to vaccine allocation, except for individuals involved in preparation of study vaccinations. The primary endpoint (first occurrence of RSV-mediated LRTD meeting one of three case definitions) was previously reported. Here, the predefined exploratory endpoint of vaccine efficacy against RSV-positive LRTD was assessed in the per-protocol efficacy set (all participants randomly assigned and vaccinated without protocol deviations affecting efficacy) through season 1 and from day 365 until the end of season 3. Humoral and cellular immunogenicity was assessed in a subset of randomly assigned and vaccinated participants. The secondary endpoint of safety through the first RSV season was previously reported; follow-up for selected safety outcomes (fatal adverse events, adverse events leading to study discontinuation, serious adverse events, and vaccine-related serious adverse events) until study completion is reported here in all randomly assigned and vaccinated participants. This trial is registered with ClinicalTrials.gov, NCT03982199 and is complete.

FINDINGS

Of 6672 adults screened, 5782 participants (2891 each receiving vaccine or placebo) were enrolled and vaccinated between Aug 5 and Nov 13, 2019. The season 2 per-protocol efficacy set included 2124 vaccine recipients and 2126 placebo recipients (season 3: 864 and 881; across three seasons: 2795 and 2803, respectively). Vaccine efficacy against RSV LRTD was 76·1% (95% CI 26·9-94·2) over seasons 2 and 3 and 78·7% (57·3-90·4) across three seasons. For those in the immunogenicity subset (vaccine n=97; placebo n=98), immune responses remained above baseline for at least 1 year. Serious adverse events occurred in 47 (2·1%) and 12 (1·3%) vaccine recipients and 45 (2·1%) and 10 (1·1%) placebo recipients during seasons 2 and 3, respectively. No treatment-related serious or fatal adverse events were reported.

INTERPRETATION

Ad26.RSV.preF-RSV preF protein maintained high efficacy against RSV LRTD in older adults across three RSV seasons.

FUNDING

Janssen Vaccines & Prevention.

Vaccines for the Elderly and Vaccination Programs in Europe and the United States

The share of the elderly population is growing worldwide as life expectancy increases. Immunosenescence and comorbidities increase infectious diseases' morbidity and mortality in older adults. Here, we aimed to summarize the latest findings on vaccines for the elderly against herpes zoster, influenza, respiratory syncytial virus (RSV), COVID-19, and pneumococcal disease and to examine vaccine recommendation differences for this age group in Europe and the United States. PubMed was searched using the keywords "elders" and "vaccine" alongside the disease/pathogen in question and paraphrased or synonymous terms. Vaccine recommendations were also sought in the European and US Centers for Disease Control and Prevention databases. Improved vaccines, tailored for the elderly, mainly by using novel adjuvants or by increasing antigen concentration, are now available. Significant differences exist between immunization policies, especially between European countries, in terms of the recipient's age, number of doses, vaccination schedule, and implementation (mandatory or recommended). Understanding the factors that influence the immune response to vaccination in the elderly may help to design vaccines that offer long-term protection for this vulnerable age group. A consensus-based strategy in Europe could help to fill the gaps in immunization policy in the elderly, particularly regarding vaccination against RSV and pneumococcus.

Epidemiological study of respiratory syncytial virus infection in adults during the pandemic of COVID-19

INTRODUCTION

While respiratory syncytial virus (RSV) is one of the most common pathogens in adults admitted to the ICU due to respiratory diseases, no reports regarding the occurrence rate of RSV infections in adults in Japan during the COVID-19 pandemic exist.

PATIENTS AND METHODS

We conducted this retrospective study to examine the exact occurrence rate of RSV infections in adults. We reviewed all patients (≥18 years) with any respiratory symptoms who received quantitative polymerase chain reaction (PCR) using nasopharyngeal samples for respiratory viruses by GeneLEAD at the Aichi Medical University Hospital between November 2022 and November 2023.

RESULTS

A total of 541 adult patients who underwent PCR test were enrolled in this study. RSV was identified in 18 cases (3.3 %); 8 (1.5 %) upper and 10 (1.8 %) lower respiratory tract infections. Influenza A and SARS-CoV-2 were found in 10 (1.8 %) and 61 (11.3 %), respectively. Patients with RSV infections and COVID-19 had more comorbidities than those with Influenza virus infections. As for RSV-associated with lower respiratory tract infection cases, 10 developed acute respiratory failure, resulting in 1 fatal case due to pneumonia and 1 died of septic shock due to ileus. The 30-, 90-day mortality rates were 1 (6 %) and 2 (11 %) respectively.

CONCLUSION

About 3 % of adults had RSV infections during the COVID-19 pandemic. The outcomes of RSV infections in adults were similar to those by COVID-19. Those with comorbidities should have a preventive method against RSV infections, the same as for COVID-19.

What's Hot This Year in Infectious Diseases Clinical Science

The field of infectious diseases saw numerous exciting advances in 2023. Trials of new antibiotics and treatment regimens sought to address rising rates of antimicrobial resistance. Other studies focused on the most appropriate use of currently available treatments, balancing the dual goals of providing effective treatment and impactful antimicrobial stewardship. Improvements in disease prevention were made through trials of both new vaccines and new chemoprophylaxis approaches. Concerning trends this year included increasing rates of invasive group A streptococcal infections, medical tourism-associated cases of fungal meningitis, and the return of locally acquired malaria to the United States. This review covers some of these notable trials and clinical developments in infectious diseases in the past year.

Cost-effectiveness of Prefusion F Protein-based Vaccines Against Respiratory Syncytial Virus Disease for Older Adults in the United States

BACKGROUND

Two prefusion F protein-based vaccines, Arexvy and Abrysvo, have been authorized by the US Food and Drug Administration for protecting older adults against respiratory syncytial virus (RSV)-associated lower respiratory tract illness. We evaluated the health benefits and cost-effectiveness of these vaccines.

METHODS

We developed a discrete-event simulation model, parameterized with the burden of RSV disease including outpatient care, hospitalization, and death for adults aged 60 years or older in the United States. Taking into account the costs associated with these RSV-related outcomes, we calculated the net monetary benefit using quality-adjusted life-year (QALY) gained as a measure of effectiveness and determined the range of price-per-dose (PPD) for Arexvy and Abrysvo vaccination programs to be cost-effective from a societal perspective.

RESULTS

Using a willingness-to-pay of $95 000 per QALY gained, we found that vaccination programs could be cost-effective for a PPD up to $127 with Arexvy and $118 with Abrysvo over the first RSV season. Achieving an influenza-like vaccination coverage of 66% for the population of older adults in the United States, the budget impact of these programs at the maximum PPD ranged from $6.48 to $6.78 billion. If the benefits of vaccination extend to a second RSV season as reported in clinical trials, we estimated a maximum PPD of $235 for Arexvy and $245 for Abrysvo, with 2-year budget impacts of $11.78 and $12.25 billion, respectively.

CONCLUSIONS

Vaccination of older adults would provide substantial direct health benefits by reducing outcomes associated with RSV-related illness in this population.

What rheumatologists need to know about mRNA vaccines: current status and future of mRNA vaccines in autoimmune inflammatory rheumatic diseases

Messenger RNA (mRNA) vaccines as a novel vaccine platform offer new tools to effectively combat both emerging and existing pathogens which were previously not possible. The 'plug and play' feature of mRNA vaccines enables swift design and production of vaccines targeting complex antigens and rapid incorporation of new vaccine constituents as needed. This feature makes them likely to be adopted for widespread clinical use in the future.Currently approved mRNA vaccines include only those against SARS-CoV-2 virus. These vaccines demonstrate robust immunogenicity and offer substantial protection against severe disease. Numerous mRNA vaccines against viral pathogens are in the early to late phase of development. Several mRNA vaccines for influenza are tested in clinical trials, with some already in phase 3 studies. Other vaccines in the early and late phases of development include those targeting Cytomegalovirus, varicella zoster virus, respiratory syncytial virus and Epstein-Barr virus. Many of these vaccines will likely be indicated for immunosuppressed populations including those with autoimmune inflammatory rheumatic diseases (AIIRD). This review focuses on the mechanism, safety and efficacy of mRNA in general and summarises the status of mRNA vaccines in development for common infectious diseases of particular interest for patients with AIIRD.

Association of respiratory infections and the impact of vaccinations on cardiovascular diseases

Influenza, pneumococcal, severe acute respiratory syndrome coronavirus 2, and respiratory syncytial virus infections are important causes of high morbidity and mortality in the elderly. Beyond the burden of infectious diseases, they are also associated with several non-infectious complications like cardiovascular events. A growing body of evidence in prospective studies and meta-analyses has shown the impact of influenza and pneumococcal vaccines on types of cardiovascular outcomes in the general population. Influenza vaccination showed a potential benefit for primary and secondary prevention of cardiovascular diseases across all ages. A reduced risk of cardiovascular events for individuals aged 65 years and older was associated with pneumococcal vaccination. Despite scientific evidence on the effectiveness, safety, and benefits of the vaccines and recommendations to vaccinate elderly patients and those with risk factors, vaccination rates remain sub-optimal in this population. Doubts about vaccine necessity or efficacy and concerns about possible adverse events in patients and physicians refer to delayed acceptance. Vaccination campaigns targeting increasing professional recommendations and public perceptions should be implemented in the coming years. The aim of this review paper is to summarize the effect of vaccination in the field of cardiovascular disease to achieve a higher vaccination rate in this patient population.

Equivalent immunogenicity across three RSVpreF vaccine lots in healthy adults 18-49 years of age: Results of a randomized phase 3 study

BACKGROUND

Bivalent RSV prefusion F subunit vaccine (RSVpreF), comprised of equal quantities of stabilized prefusion F antigens from the major circulating subgroups (RSV A, RSV B), is licensed for prevention of RSV-associated lower respiratory tract illness (LRTI) in older adults and for maternal vaccination for prevention of RSV-associated LRTI in infants. To support licensure and large-scale manufacturing, this lot consistency study was conducted to demonstrate equivalence in immunogenicity across 3 RSVpreF lots.

METHODS

This phase 3, multicenter, parallel-group, placebo-controlled, randomized (1:1:1:1), double-blind study evaluated immunogenicity, safety, and tolerability of RSVpreF in healthy 18-49-year-old adults. Participants received a single 120-µg injection of 1 of 3RSVpreF lots or placebo. Geometric mean ratio (GMR) of RSV serum 50 % neutralizing geometric mean titers obtained 1 month after vaccination were compared between each vaccine lot for RSV A and RSV B, separately. Equivalence between lots was defined using a 1.5-fold criterion (GMR 95 % CIs for every lot pair within the 0.667-1.5 interval). Safety and tolerability were assessed.

RESULTS

Of 992participants vaccinated, 948 were included in the evaluable immunogenicity population. All 3 RSVpreF lots elicited strong immune responses, meeting the 1.5-fold equivalence criterion for all between-lot comparisons for both RSV A and RSV B. Across the 3 lots, RSV A and RSV B 50 % neutralizing geometric mean titers substantially increased from baseline (RSV A, 1671-1795; RSV B 1358-1429) to 1 month after RSVpreF vaccination (RSV A, 24,131-25,238; RSV B, 19,238-21,702), corresponding to ≥14-fold increases in 50 % neutralizing titers for both RSV A and RSV B from before to 1 month after vaccination. Single doses of RSVpreF were safe and well tolerated, with similar safety profiles across the 3 RSVpreF lots.

CONCLUSIONS

These findings support the reproducibility of RSVpreF vaccine manufacturing with similar safety and reactogenicity profiles (NCT05096208).

Age-Stratified Seroprevalence of Respiratory Syncytial Virus: Analysis Using Prefusion F and G Protein Antibodies

This is a cross-sectional serosurveillance study for RSV. Between June and September of 2021, a total of 150 sera were collected from 30 individuals in each age group (<5, 5-18, 19-49, 50-64, and ≥65 years). Seroprevalence was estimated using enzyme-linked immunosorbent assays targeting two stabilized prefusion F (preF; DS-Cav1 and SC-TM) and G proteins. The overall seroprevalence was low in young children and older adults, despite them having a higher risk of severe RSV infection. There was a remarkable difference in age-stratified seroprevalence rates between anti-preF and anti-G protein antibodies. Given the high disease burden and low seroprevalence in both infants and old adults, RSV vaccination would be crucial for pregnant women and people aged over 60 years.

Efficacy, immunogenicity and safety of respiratory syncytial virus prefusion F vaccine: systematic review and meta-analysis

OBJECTIVE

A notable research gap exists in the systematic review and meta-analysis concerning the efficacy, immunogenicity, and safety of the respiratory syncytial virus (RSV) prefusion F vaccine.

METHODS

We conducted a comprehensive search across PubMed, Embase, the Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov to retrieve articles related to the efficacy, immunogenicity, and safety of RSV prefusion F vaccines, published through September 8, 2023. We adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

RESULTS

A total of 22 randomized controlled trials involving 78,990 participants were included in this systematic review and meta-analysis. The RSV prefusion F vaccine exhibited a vaccine effectiveness of 68% (95% CI: 59-75%) against RSV-associated acute respiratory illness, 70% (95% CI: 60-77%) against medically attended RSV-associated lower respiratory tract illness, and 87% (95% CI: 71-94%) against medically attended severe RSV-associated lower respiratory tract illness. Common reported local adverse reactions following RSV prefusion F vaccination include pain, redness, and swelling at the injection site, and systemic reactions such as fatigue, headache, myalgia, arthralgia, nausea, and chills.

CONCLUSIONS

Our meta-analysis suggests that vaccines using the RSV prefusion F protein as antigen exhibit appears broadly acceptable efficacy, immunogenicity, and safety in the population. In particular, it provides high protective efficiency against severe RSV-associated lower respiratory tract disease.

Efficacy of Respiratory Syncytial Virus Vaccination to Prevent Lower Respiratory Tract Illness in Older Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

A systematic review and meta-analysis was designed in order to ascertain the effectiveness of respiratory syncytial virus (RSV) vaccination in preventing lower respiratory tract diseases (LRTD) in older adults (age ≥ 60 years). Studies reporting on randomized controlled trials (RCTs) were searched for in three databases (PubMed, Embase, and Scopus) and the preprint repository medRxiv until 31 March 2024. A total of nine studies were eventually included, two of which were conference proceedings. Our analysis included five RCTs on five RSV vaccines (RSVpreF, RSVPreF3, Ad26.RSV.preF, MEDI7510, and mRNA-1345). The meta-analysis documented a pooled vaccine efficacy of 81.38% (95% confidence interval (95% CI) 70.94 to 88.06) for prevention of LRTD with three or more signs/symptoms during the first RSV season after the delivery of the vaccine. Follow-up data were available for RSVPreF3 (2 RSV seasons), RSVpreF (mid-term estimates of second RSV season), and mRNA-1345 (12 months after the delivery of the primer), with a pooled VE of 61.15% (95% CI 45.29 to 72.40). After the first season, the overall risk for developing RSV-related LRTD was therefore substantially increased (risk ratio (RR) 4.326, 95% CI 2.415; 7.748). However, all estimates were affected by substantial heterogeneity, as suggested by the 95% CI of I2 statistics, which could be explained by inconsistencies in the design of the parent studies, particularly when dealing with case definition. In conclusion, adult RSV vaccination was quite effective in preventing LRTD in older adults, but the overall efficacy rapidly decreased in the second season after the delivery of the vaccine. Because of the heterogenous design of the parent studies, further analyses are required before tailoring specific public health interventions.

Respiratory Syncytial Virus-Associated Respiratory Diseases in Children and Adults

BACKGROUND

Respiratory syncytial virus (RSV) is a common cause of lower respiratory tract infections (LRTI), particularly in neonates, infants and young children, with approximately 33 million infections worldwide each year. 1-2% of episodes lead to hospitalization. There are hardly any reliable epidemiological figures on hospital - ization in adults, whose burden of disease from RSV is probably markedly underestimated.

METHODS

This review is based on publications retrieved by a selective search in PubMed, with particular attention to recommendations for the prevention of RSV infection.

RESULTS

There is no approved antiviral therapy for clinical practice, but preventive strategies are increasingly becoming available. Passive immunization in infants is well tolerated and highly effective, as is the active vaccination of pregnant women to prevent severe RSV infection in young infants. The former was found to lower the frequency of severe LRTI (5/4037 in the vaccination group vs. 19/4031 individuals in the placebo group), yielding an efficacy of 75.7%; for the latter, the corresponding findings were a reduction to 19/3682 in the vaccination group vs. 62/3676 in the placebo group, or 69.4% efficacy. For the active vaccination of older adults, both a recombinant vaccine with adjuvant and a bivalent vaccine have recently been approved. These, too, are well tolerated and highly effective: the former lowered the frequency of severe LRTI to 1/12466 in the vaccination group vs. 17/12494 in the placebo group (94.1% efficacy), while the latter lowered the frequency of LRTI with 3 or more manifestations to 2/17215 in the vaccination group vs. 14/17069 in the placebo group (85.7% efficacy).

CONCLUSION

The approval of new RSV-specific monoclonal antibodies and active vaccinations enables targeted prevention of RSV infection in the main population groups at risk.

P. G, Potdar V, Manna B, Amarchand R, Choudekar A, Gopal G, Sarda K, Lafond KE, Azziz-Baumgartner E, Saha S, Dar L, Krishnan A. Adverse outcomes in patients hospitalized with pneumonia at age 60 or more: A prospective multi-centric hospital-based study in India

BACKGROUND

Limited data exists regarding risk factors for adverse outcomes in older adults hospitalized with Community-Acquired Pneumonia (CAP) in low- and middle-income countries such as India. This multisite study aimed to assess outcomes and associated risk factors among adults aged ≥60 years hospitalized with pneumonia.

METHODS

Between December 2018 and March 2020, we enrolled ≥60-year-old adults admitted within 48 hours for CAP treatment across 16 public and private facilities in four sites. Clinical data and nasal/oropharyngeal specimens were collected by trained nurses and tested for influenza, respiratory syncytial virus (RSV), and other respiratory viruses (ORV) using the qPCR. Participants were evaluated regularly until discharge, as well as on the 7th and 30th days post-discharge. Outcomes included ICU admission and in-hospital or 30-day post-discharge mortality. A hierarchical framework for multivariable logistic regression and Cox proportional hazard models identified risk factors (e.g., demographics, clinical features, etiologic agents) associated with critical care or death.

FINDINGS

Of 1,090 CAP patients, the median age was 69 years; 38.4% were female. Influenza viruses were detected in 12.3%, RSV in 2.2%, and ORV in 6.3% of participants. Critical care was required for 39.4%, with 9.9% in-hospital mortality and 5% 30-day post-discharge mortality. Only 41% of influenza CAP patients received antiviral treatment. Admission factors independently associated with ICU admission included respiratory rate >30/min, blood urea nitrogen>19mg/dl, altered sensorium, anemia, oxygen saturation <90%, prior cardiovascular diseases, chronic respiratory diseases, and private hospital admission. Diabetes, anemia, low oxygen saturation at admission, ICU admission, and mechanical ventilation were associated with 30-day mortality.

CONCLUSION

High ICU admission and 30-day mortality rates were observed among older adults with pneumonia, with a significant proportion linked to influenza and RSV infections. Comprehensive guidelines for CAP prevention and management in older adults are needed, especially with the co-circulation of SARS-CoV-2.

Infectious Diseases: What You May Have Missed in 2023

In 2023, published research on COVID-19 remains prominent. The aim of this article is to highlight important developments in infectious disease evidence unrelated to COVID-19 that were published in 2023. The literature was screened for sound new evidence relevant to internal medicine specialists and subspecialists whose focus of practice is not infectious diseases. The highlighted publications relate to various organisms and patient populations. One article provides insight into the updated guidelines for the diagnosis and management of infective endocarditis. Several articles address the management of sepsis and bacteremia: comparison of cefepime versus piperacillin-tazobactam, ceftobiprole for the treatment of complicated Staphylococcus aureus bacteremia, and early switch from intravenous to oral antibiotics in patients with gram-negative bacteremia. Another article examines differences in all-cause mortality in patients with Clostridioides difficile infection who receive different treatments. Additional articles provide evidence about the treatment of patients with HIV infection: the utility of preexposure prophylaxis to prevent HIV infection, the efficacy of pitavastatin in reducing cardiovascular disease, and the efficacy of dexamethasone for the treatment of tuberculous meningitis in persons with HIV.

Viral infections causing asthma exacerbations in the age of biologics and the COVID-19 pandemic

PURPOSE OF REVIEW

Asthma exacerbations are associated with substantial symptom burden and healthcare costs. Viral infections are the most common identified cause of asthma exacerbations. The epidemiology of viral respiratory infections has undergone a significant evolution during the COVID-19 pandemic. The relationship between viruses and asthmatic hosts has long been recognized but it is still incompletely understood. The use of newly approved asthma biologics has helped us understand this interaction better.

RECENT FINDINGS

We review recent updates on the interaction between asthma and respiratory viruses, and we address how biologics and immunotherapies could affect this relationship by altering the respiratory mucosa cytokine milieu. By exploring the evolving epidemiological landscape of viral infections during the different phases of the COVID-19 pandemic, we emphasize the early post-pandemic stage, where a resurgence of pre-pandemic viruses with atypical seasonality patterns occurred. Finally, we discuss the newly developed RSV and SARS-CoV-2 vaccines and how they reduce respiratory infections.

SUMMARY

Characterizing how respiratory viruses interact with asthmatic hosts will allow us to identify tailored therapies to reduce the burden of asthma exacerbations. New vaccination strategies are likely to shape the future viral asthma exacerbation landscape.

Pulmonology: What You May Have Missed in 2023

The field of pulmonology saw significant advances in 2023. The publications highlighted in this article address advances and changes in practice related to asthma, chronic obstructive pulmonary disease (COPD), interstitial lung disease, pleural disorders, and sleep-disordered breathing. One article reviews data examining the efficacy of vaccination against respiratory syncytial virus, a respiratory viral illness that has had devastating effects globally. Four studies evaluate the role of various therapies in COPD, including dupilumab, ensifentrine, pulmonary rehabilitation programs, and lung volume reduction versus endobronchial valves. Another study explores the effect on vascular events of positive-pressure ventilation in patients with sleep-disordered breathing and recent stroke. The use of combination therapy with rituximab and mycophenolate mofetil on progression-free survival in patients with nonspecific interstitial pneumonia is the topic of another study. We also highlight an update of clinical recommendations for the evaluation of patients with pleural disorders and a systematic review analyzing the effectiveness of inhaled corticosteroids as a supplement to dual therapy for COPD.

Development of innate and adaptive immunity to RSV in young children

Infection of the respiratory tract with respiratory syncytial virus (RSV) is common and occurs repeatedly throughout life with most severe disease occurring at the extremes of age: in young infants and the elderly. Effective anti-viral therapeutics are not available and therefore prevention has been the primary strategy for reducing the disease burden. Our current understanding of respiratory mucosal cell biology and the immune response within the respiratory tract is inadequate to prevent infection caused by a pathogen like RSV that does not disseminate outside of this environment. Gaps in our understanding of the activation of innate and adaptive immunity in response to RSV and the role of age upon infection also limit improvements in the design of therapeutics and vaccines for young infants. However, advancements in structural biology have improved our ability to characterize antibodies against viral proteins and in 2023 the first vaccines for those over 60 years and pregnant women became available, potentially reducing the burden of disease. This review will examine our current understanding of the critical facets of anti-RSV immune responses in infants and young children as well as highlight areas where more research is needed.