Estimation of the Number of Respiratory Syncytial Virus-Associated Hospitalizations in Adults in the European Union

Respiratory syncytial virus vaccination in older adults and patients with chronic disorders: A position paper from the Portuguese Society of Pulmonology, the Portuguese Association of General and Family Medicine, the Portuguese Society of Cardiology, the Portuguese Society of Infectious Diseases and Clinical Microbiology, the Portuguese Society of Endocrinology, Diabetes and Metabolism, and the Portuguese Society of Internal Medicine

BACKGROUND

Respiratory syncytial virus (RSV) is an important cause of lower respiratory tract infection, hospitalisation and death in adults.

METHODS

Based on evidence regarding the impact of RSV on adult populations at risk for severe infection and the efficacy and safety of RSV vaccines, the Portuguese Society of Pulmonology, the Portuguese Association of General and Family Medicine, the Portuguese Society of Cardiology, the Portuguese Society of Infectious Diseases and Clinical Microbiology, the Portuguese Society of Endocrinology, Diabetes and Metabolism, and the Portuguese Society of Internal Medicine endorses this position paper with recommendations to prevent RSV-associated disease and its complications in adults through vaccination.

CONCLUSION

The RSV vaccine is recommended for people aged ≥50 years with risk factors (chronic obstructive pulmonary disease, asthma, heart failure, coronary artery disease, diabetes, chronic kidney disease, chronic liver disease, immunocompromise, frailty, dementia, and residence in a nursing home) and all persons aged ≥60 years. If it cannot be made available to this population, then the vaccine should be prioritised for individuals aged ≥75 years and those aged ≥50 years with risk factors. The vaccine should preferably be given between September and November and can be co-administered with the influenza vaccine. Ongoing studies on RSV vaccines may justify extending these recommendations in the future.

Hospitalization cost estimates of respiratory syncytial virus and influenza infections in adults in Spain, 2016-2019

Respiratory syncytial virus (RSV) is increasingly a recognized cause of severe respiratory infection among adults. This retrospective observational study compared the costs of RSV and influenza hospitalizations in adults aged ≥18 years admitted to the Spanish National Healthcare System between 2016 and 2019. Mean costs per hospitalization episode were compared using a multivariable log-gamma generalized linear model adjusted by age, risk group and calendar year. Total annual hospitalization costs were estimated from population incidence rates (for RSV we used model-based rates reported in a published study due to the substantial under-ascertainment of cases) and the mean cost per episode. ICD-10 codes identified a total of 11,662 adults hospitalized with RSV and 79,319 with influenza. The mean length of stay was longer for RSV than for influenza in low-risk patients aged 60-79 years, moderate-risk patients (those with chronic medical conditions) aged ≥50 years and in high-risk (those with immunocompromising conditions) patients aged <80 years. There were no differences in intensive care unit (ICU) admission (except for higher admission in high-risk RSV patients aged 70-79 years), ICU stay or in-hospital case fatality rate. Mean costs per hospitalization episode were also similar: RSV €3870 (95 % CI 3773-3942) vs influenza €3888 (95 % CI 3836-3931). Total annual costs for RSV-attributable hospitalizations were estimated at M€194, twice than that of influenza (M€83). Annual costs increased by 11 % over the study period for RSV and by 47 % for influenza. In 2019, adults aged ≥60 years and ≥ 70 years contributed 91 % and 82 %, respectively, of the total RSV-attributable hospitalization costs in adults. RSV has a significant economic burden to the Spanish National Healthcare System, likely greater than influenza. Efficacious RSV vaccines and antivirals have the potential for high public health impact.

Adult vaccinations against respiratory infections

INTRODUCTION

Lower respiratory infections have a huge impact on global health, especially in older individuals, immunocompromised people, and those with chronic comorbidities. The COVID-19 pandemic highlights the importance of vaccination. However, there are lower rates of vaccination in the adult population that are commonly due to a missed opportunity to vaccinate. Vaccination offers the best strategy to prevent hospitalization, complications, and death caused by lower respiratory infections.

AREAS COVERED

In this review, the authors provide an overview of the vaccines for lower respiratory infections in the adult population. The review highlights the available data about the impact of vaccines on preventing respiratory infections, focusing on the pneumococcal vaccine, influenza vaccine, COVID-19 vaccines, and respiratory syncytial virus (RSV) vaccines. The authors discuss the currently available scientific evidence on the role of vaccines against respiratory infections. Finally, the authors review the current recommendations for vaccines in the adult population.

EXPERT OPINION

Scientific evidence on the effectiveness of vaccines against respiratory infections is important. An efficient implementation of adult immunization strategies will provide an opportunity to decrease the global burden of lower respiratory infections. Recognizing the existing vaccines and their recommendations for the adult population is essential to achieve a high vaccination rate in the population.

Prevalence of Respiratory Syncytial Virus Infection in Hospitalized COPD Patients in Spain Between 2018-2022

BACKGROUND

Respiratory syncytial virus (RSV) infection is a common cause of hospital admission. The association between chronic obstructive pulmonary disease (COPD) exacerbation and RSV infection is not well studied.

OBJECTIVE

To analyze the hospitalizations of patients with COPD and RSV infection in Spain between 2018 and 2022.

METHODS

The data used were obtained from the Spanish Hospital Discharge Database. We selected subjects aged ≥40 years diagnosed with COPD, admitted to the hospital from 1 January 2018 to 31 December 2022. The COPD population that met the selection criteria was subdivided based on the presence of an ICD-10 code for RSV infection. To obtain comparable populations, for each subject with COPD and RSV infection, a subject without an RSV code was selected, with the COPD code in the same diagnostic position (1 to 20), as well as the same year of admission, sex, and age.

RESULTS

Among subjects aged ≥40 years, 1,429,288 were identified as having COPD, of whom 5673 also had RSV infection. The number of hospitalizations with COPD and RSV infection increased during the study period. The proportion of RSV infection among patients admitted for COPD increased significantly over time, from 0.32% in 2018 to 0.65% in 2022, p < 0.001. In-hospital mortality (IHM) increased over time, but the differences were not significant (6.23% in 2018 vs. 6.79% in 2022). Patients with COPD and RSV infection had, compared with those without RSV infection, a higher use of mechanical ventilation, both invasive (3.44% vs. 1.34%, p < 0.001) and noninvasive (8.09% vs. 4.51%, p < 0.001) and a higher proportion of intensive care unit (ICU) admission (7.21% vs. 3.9%, p < 0.001). After multivariate adjustment, a significant increase in IHM was found from 2018 to 2022 in subjects with and without RSV infection. The presence of RSV infection was associated with a higher mortality (OR 1.22; 95% CI 1.01-1.46).

CONCLUSIONS

The proportion of RSV infection among patients admitted for COPD increased significantly over time. Patients with COPD and RSV infection had, compared with those without RSV infection, a higher severity, a higher use of mechanical ventilation, and a higher proportion of ICU admission. The presence of RSV infection was associated with IHM. These results can help to identify patients at higher risk and make decisions to avoid the increased risk of hospitalization and mortality in this population.

Impact of RSVpreF vaccination on reducing the burden of respiratory syncytial virus in infants and older adults

Respiratory syncytial virus (RSV) causes a substantial health burden among infants and older adults. Prefusion F protein-based vaccines have shown high efficacy against RSV disease in clinical trials, offering promise for mitigating this burden through maternal and older adult immunization. Employing an individual-based model, we evaluated the impact of RSV vaccination on hospitalizations and deaths in 13 high-income countries, assuming that the vaccine does not prevent infection or transmission. Using country-specific vaccine uptake rates for seasonal influenza, we found that vaccination of older adults would prevent hospitalizations by a median of 35-64% across the countries studied here. Vaccination of pregnant women could avert infant hospitalizations by 5-50%. Reductions in RSV-related mortality mirrored those estimated for hospitalizations. While substantial hospitalization costs could be averted, the impact of vaccination depends critically on uptake rates. Enhancing uptake and accessibility is crucial for maximizing the real-world impact of vaccination on reducing RSV burden among vulnerable populations.

Respiratory syncytial virus pulmonary infections in adults - disease burden and prevention

PURPOSE OF REVIEW

We highlight the evolving understanding of the burden of respiratory syncytial virus (RSV) in older adults and recent data on the three new vaccines.

RECENT FINDINGS

As well as a greater recognition of the amount of RSV infection in adults, and especially over 60 years of age, there has been a significant amount of study detailing the postacute burden including excess cardiovascular disease and loss of physical and cognitive functioning. Three new RSV vaccines now have published data for two seasons, and while direct comparison is not possible due to differences in the timing, methodology and populations studies, all show good efficacy with no serious side effects of concern.

SUMMARY

RSV causes a substantial amount of morbidity and mortality in older adults with both acute and longer term impacts. With effective vaccines now available clinicians should be advocating with their patients to prevent RSV infection.

RSV vaccination as the optimal prevention strategy for older adults

Respiratory syncytial virus (RSV) is a respiratory virus that usually causes mild upper respiratory tract symptoms. However, it can lead to a severe lower respiratory tract disease in high-risk populations, with severe complications such as pneumonia and respiratory failure. RSV poses a significant public health threat not only to children, but also to adults, particularly those over 75 years of age and individuals with comorbidities. The high incidence and severity of RSV infections in these vulnerable groups highlights the urgent need for effective preventive strategies. Despite advancements in the clinical management of respiratory infections, preventing RSV remains a significant challenge. The symptoms of RSV are often underestimated and misdiagnosed due to their similarity to other respiratory infections like influenza and COVID-19. This leads to a substantial disease burden not only for patients but also for healthcare systems, due to increased hospitalizations and prolonged treatments. In recent years, there has been a significant progress in the development of RSV vaccines, offering new hope for disease prevention. Our aim is to promote RSV vaccination, emphasizing the importance of large-scale prevention efforts to enhance the quality of life for at-risk individuals and optimize healthcare resource allocation. This paper will report efficacy and safety data for the three main vaccines currently available for healthcare practitioners, providing a comprehensive and balanced overview of vaccine options and supporting informed decision-making by healthcare professionals and regulatory authorities.

Respiratory Syncytial Virus: A WAidid Consensus Document on New Preventive Options

Background/Objectives: Respiratory syncytial virus (RSV) is a leading cause of respiratory infections, particularly affecting young infants, older adults, and individuals with comorbidities. Methods: This document, developed as a consensus by an international group of experts affiliated with the World Association of Infectious Diseases and Immunological Disorders (WAidid), focuses on recent advancements in RSV prevention, highlighting the introduction of monoclonal antibodies (mAbs) and vaccines. Results: Historically, RSV treatment options were limited to supportive care and the monoclonal antibody palivizumab, which required multiple doses. Recent innovations have led to the development of long-acting mAbs, such as nirsevimab, which provide season-long protection with a single dose. Nirsevimab has shown high efficacy in preventing severe RSV-related lower respiratory tract infections (LRTIs) in infants, reducing hospitalizations and ICU admissions. Additionally, new vaccines, such as RSVpreF and RSVpreF3, target older adults and have demonstrated significant efficacy in preventing LRTIs in clinical trials. Maternal vaccination strategies also show promise in providing passive immunity to newborns, protecting them during the most vulnerable early months of life. This document further discusses the global burden of RSV, its economic impact, and the challenges of implementing these preventative strategies in different healthcare settings. Conclusions: The evidence supports the integration of both passive (mAbs) and active (vaccines) immunization approaches as effective tools to mitigate the public health impact of RSV. The combined use of these interventions could substantially reduce RSV-related morbidity and mortality across various age groups and populations, emphasizing the importance of widespread immunization efforts.

Burden of Respiratory Syncytial Virus Infection in Children and Older Patients Hospitalized with Asthma: A Seven-Year Longitudinal Population-Based Study in Spain

(1) Background: To describe hospitalizations due to respiratory syncytial virus (RSV) infection among children and elderly patients with asthma. (2) Methods: We used a nationwide discharge database to select patients with asthma aged 0 to 15 years and ≥65 years admitted to Spanish hospitals from 2016 to 2022. (3) Results: We identified 49,086 children and 471,947 elderly patients hospitalized with asthma (3.52% and 0.51%, respectively, with RSV). The proportion of RSV increased over time in children with asthma (from 1.44% to 7.4%, p < 0.001) and in elderly individuals (from 0.17% to 1.01%, p < 0.001). Among children with RSV infection, the presence of influenza (OR 3.65; 95% CI 1.46-9.1) and pneumonia (OR 1.85; 95% CI 1.02-3.55) increased the risk of poor outcome. The presence of RSV was associated with severity in these patients, defined by use of mechanical ventilation and/or admission to the intensive care unit (OR 1.44; 95% CI 1.11-1.86). In elderly patients with RSV infection, older age, congestive heart failure, COVID-19, and pneumonia increased the risk of in-hospital mortality (IHM). However, RSV infection was not associated with IHM (OR 0.88; 95% CI 0.68-1.15) in these patients. (4) Conclusion: Our results highlight the impact of RSV infection in children and elderly patients hospitalized with asthma. Strategies to improve surveillance, prophylaxis, and management of RSV infection should be evaluated.

Severity of respiratory syncytial virus compared with SARS-CoV-2 and influenza among hospitalised adults ≥65 years

INTRODUCTION

Our aim was to estimate the risk of pneumonia, admission to intensive care unit (ICU) or death in individuals ≥65 years old admitted to hospital with RSV, compared to influenza or COVID-19.

METHODS

We included hospitalised patients from Severe Acute Respiratory Infection Surveillance in Spain between 2021-2024, aged ≥65 years, laboratory confirmed for RSV, influenza or SARS-CoV-2. Using a binomial regression with logarithmic link, we estimated the relative risk (RR) of pneumonia, ICU admission and in-hospital mortality, in patients with RSV compared to influenza or SARS-CoV-2, adjusting for age, sex, season and comorbidities. We stratified the estimates by vaccination status for influenza or SARS-CoV2.

RESULTS

Among patients unvaccinated for influenza or SARS-CoV-2, those with RSV had similar or lower risk of pneumonia [vs. influenza: RR= 0.91 (95% Confidence Interval: 0.72-1.16); vs. SARS-CoV-2: 0.81 (0.67-0.98)], ICU admission [vs. influenza: 0.93 (0.41-2.08); vs. SARS-CoV-2: 1.10 (0.61-1.99)] and mortality [vs. influenza: 0.64 (0.32-1.28); vs. SARS-CoV-2: 0.56 (0.30-1.04)]. Among the vaccinated, results were largely similar except for a higher risk of ICU admission with RSV [vs. influenza: 2.13(1.16-3.89); vs. SARS-CoV-2: 1.83 (1.02-3.28)] CONCLUSIONS: RSV presented similar or lower intrinsic severity than influenza or SARS-CoV2. Among vaccinated patients, RSV was associated to higher ICU-admission, suggesting the potential for preventive RSV vaccination.

Cost-Effectiveness of Bivalent Respiratory Syncytial Virus Prefusion F Vaccine for Prevention of Respiratory Syncytial Virus Among Older Adults in Greece

BACKGROUND/OBJECTIVES

To evaluate the health benefits, costs, and cost-effectiveness of vaccination with bivalent respiratory syncytial virus stabilized prefusion F vaccine (RSVpreF) for the prevention of lower respiratory tract disease caused by respiratory syncytial virus (RSV) in Greek adults 60 years of age and older.

METHODS

A Markov model was adapted to simulate lifetime risk of health and economic outcomes from the public payer's perspective over a lifetime horizon. Epidemiology, vaccine effectiveness, utilities, and direct medical costs (EUR, 2024) were obtained from published studies, official sources, and local experts. Model outcomes included the number of medically attended RSV cases, stratified by care setting (i.e., hospital, emergency department [ED], outpatient visits [OV]), and attributable RSV-related deaths, costs, life years (LY), quality-adjusted life-years (QALY), and incremental cost-effectiveness ratios (ICERs) of RSVpreF vaccination compared with no vaccination.

RESULTS

The model projected 258,170 hospitalizations, 112,248 ED encounters, 1,201,604 OV, and 25,463 deaths related to RSV in Greek older adults resulting in direct medical costs of EUR 1.6 billion over the lifetime horizon. Assuming RSV vaccination would reach the same coverage rates as pneumococcal and influenza programmes, 18,118 hospitalizations, 7874 ED encounters, 48,079 OV, and 1706 deaths could be prevented over the modelled time horizon. The health benefits associated with RSVpreF contributed to an incremental gain of 10,976 LYs and 7230 QALYs compared with no vaccination. The incremental analysis reported that vaccination with RSVpreF was estimated to be a cost-effective strategy resulting in ICERs of EUR 12,991 per LY gained, EUR 19,723 per QALY gained, and EUR 7870 per hospitalized RSV case avoided compared with no vaccination.

CONCLUSIONS

Vaccination with RSVpreF was a cost-effective strategy for the prevention of RSV disease in Greek adults over 60 years of age. The introduction of RSV vaccination can improve public health by averting RSV cases and deaths and has the potential to fulfil an unmet medical need.

Effectiveness and efficiency of immunisation strategies to prevent RSV among infants and older adults in Germany: a modelling study

BACKGROUND

Recently, several novel RSV immunisation products that protect infants and older adults against RSV disease have been licensed in Europe. We estimated the effectiveness and efficiency of introducing these RSV immunisation strategies in Germany.

METHODS

We used a Bayesian framework to fit a deterministic age-structured dynamic transmission model of RSV to sentinel surveillance and RSV-specific hospitalisation data in Germany from 2015 to 2019. The calibrated model was used to evaluate different RSV intervention strategies over 5 years: long-acting, single-dose monoclonal antibodies (mAbs) in high-risk infants aged 1-5 months; long-acting mAbs in all infants aged 1-5 months; seasonal vaccination of pregnant women and one-time seasonal vaccination of older adults (75 + /65 + /55 + years). We performed sensitivity analysis on vaccine uptake, seasonal vs. year-round maternal vaccination, and the effect of under-ascertainment for older adults.

RESULTS

The model was able to match the various RSV datasets. Replacing the current short-acting mAB for high-risk infants with long-acting mAbs prevented 1.1% of RSV-specific hospitalisations in infants per year at the same uptake. Expanding the long-acting mAB programme to all infants prevented 39.3% of infant hospitalisations per year. Maternal vaccination required a larger number to be immunised to prevent one additional hospitalisation than a long-acting mAB for the same uptake. Vaccination of adults older than 75 years at an uptake of 40% in addition to Nirsevimab in all infants prevented an additional 4.5% of all RSV hospitalisations over 5 years, with substantial uncertainty in the correction for under-ascertainment of the RSV burden.

CONCLUSIONS

Immunisation has the potential to reduce the RSV disease burden in Germany.

Efficacy of anti-RSV vaccination in preventing respiratory syncytial virus disease and severe illness in older adults: a systematic review of randomized controlled trials

PURPOSE

Several vaccines against respiratory syncytial virus (RSV) are being developed. The objective of this systematic review is to determine the efficacy of these vaccines in preventing RSV disease in adults over 60 years of age, especially regarding severe illness.

METHODS

We researched MEDLINE, CENTRAL, Scopus, medRxiv, bioRxiv and ClinicalTrials.gov until April/2024. Randomized controlled trials studying an anti-RSV vaccine in adults above 60 years and reporting RSV-related acute respiratory infection/disease (ARI/ARD), lower respiratory tract infection/disease (LRTI/LRTD) and severe LRTI/LRTD were included. Vaccine efficacy was calculated as ([1 - risk ratio] × 100). Risk of bias and certainty of evidence were assessed by RoB2 tool and GRADE approach. The meta-analytical relative risk of ARI/ARD and LRTI/LRTD was estimated, with a subgroup analysis performed according to the vaccine type. The random effects model was used.

RESULTS

We included seven studies, five addressing prefusion vaccines and two regarding non-prefusion ones. The number of RSV-related LRTI/LRTD cases was reduced by vaccination, with a relative risk of 0.39 [CI 95% 0.22 to 0.69] and a vaccine efficacy of 61%. Considering the subgroup of prefusion vaccines alone, there is a relative risk of 0.27 [CI 95% 0.19 to 0.36] for LRTI/LRTD and a vaccine efficacy of 73%. ARI/ARD incidence presented a similar pattern. Only one trial reports results for severe LRTI/LRTD, with a vaccine efficacy of 94.1% [95% CI 62.4 to 99.9].

CONCLUSIONS

Prefusion anti-RSV vaccines are efficacious in the prevention of LTRI/LTRD and ARI/ARD cases. More studies regarding severe LTRI/LTRD are necessary in the future.

Clinical Manifestations and Outcomes in Adults Hospitalized With Respiratory Syncytial Virus and Influenza a/B: A Multicenter Observational Cohort Study

Background

Respiratory syncytial virus (RSV) and influenza cause significant health challenges, particularly for individuals with comorbid conditions and older adults. However, information on the clinical manifestations and outcomes of adults hospitalized with RSV in Europe remains limited.

Methods

This multicenter observational cohort study of adults hospitalized with RSV or influenza A or B from March 2016 to April 2020 investigated the clinical manifestations, mortality risk factors, and association with 90-day mortality rates by logistic regression analysis after adjustment for covariates.

Results

Of 988 patients hospitalized with either virus, 353 had RSV, 347 had influenza A, and 288 had influenza B infection. Patients with RSV, compared with those with influenza A or B, were more likely to have comorbid conditions (83% for RSV vs 72% for influenza A [P = .03] and 74% for influenza B [P = .001]) or pneumonia (41% vs 29% [P = .03] and 24% [P < .001], respectively). After adjustment for covariates, RSV infection was associated with an increased all-cause mortality rate within 90 days compared with influenza B (odds ratio, 2.16 [95% confidence interval, 1.20-3.87]; P = .01) but not influenza A (1.38 [.84-2.29]; P = .21). Increasing age and present pneumonia were identified as independent mortality risk factors in patients with RSV.

Conclusions

Older adults hospitalized with RSV infections are at a higher risk of dying within 90 days of hospitalization than patients admitted with influenza B but at a similar risk as those admitted with influenza A, emphasizing the detrimental effects and severity of older patients being infected with RSV. Our findings underscore the need for strategic testing and vaccination approaches to mitigate the impact of RSV among older adults.

Role of Poly(A)-Binding Protein Cytoplasmic 1, a tRNA-Derived RNA Fragment-Bound Protein, in Respiratory Syncytial Virus Infection

Respiratory Syncytial Virus (RSV) is a significant cause of lower respiratory tract infections (LRTI) across all demographics, with increasing mortality and morbidity among high-risk groups such as infants under two years old, the elderly, and immunocompromised individuals. Although newly approved vaccines and treatments have substantially reduced RSV hospitalizations, accessibility remains limited, and response to treatment varies. This underscores the importance of comprehensive studies on host-RSV interactions. tRNA-derived RNA fragments (tRFs) are recently discovered non-coding RNAs, notable for their regulatory roles in diseases, including viral infections. Our prior work demonstrated that RSV infection induces tRFs, primarily derived from the 5'-end of a limited subset of tRNAs (tRF5), to promote RSV replication by partially targeting the mRNA of antiviral genes. This study found that tRFs could also use their bound proteins to regulate replication. Our proteomics data identified that PABPC1 (poly(A)-binding protein cytoplasmic 1) is associated with tRF5-GluCTC, an RSV-induced tRF. Western blot experimentally confirmed the presence of PABPC1 in the tRF5-GluCTC complex. In addition, tRF5-GluCTC is in the anti-PABPC1-precipitated immune complex. This study also discovered that suppressing PABPC1 with its specific siRNA increased RSV (-) genome copies without impacting viral gene transcription, but led to less infectious progeny viruses, suggesting the importance of PABPC1 in virus assembly, which was supported by its interaction with the RSV matrix protein. Additionally, PABPC1 knockdown decreased the production of the cytokines MIP-1α, MIP-1β, MCP-1, and TNF-α. This is the first observation suggesting that tRFs may regulate viral infection via their bound proteins.

Burden of Respiratory Syncytial Virus (RSV) Infection Among Adults in Nursing and Care Homes: A Systematic Review

BACKGROUND

Older adults in nursing and care homes (NCHs) are vulnerable to severe respiratory syncytial virus (RSV) infection, hospitalization, and death. This study aimed to gather data on RSV disease among older adults in NCHs and identify reported risk factors for RSV hospitalization and case fatality.

METHODS

The study protocol was registered in PROSPERO (CRD42022371908). We searched MEDLINE, EMBASE, and Global Health databases to identify articles published between 2000 and 2023. Observational and experimental studies conducted among older adults in NCHs requiring assistive care and reporting RSV illness were included and relevant data were extracted.

RESULTS

Of 18,690 studies screened, 32 were selected for full-text review, and 20 were included. Overall, the number of NCH residents ranged from 42 to 1459 with a mean age between 67.6 and 85 years. Attack rates ranged from 6.7% to 47.6% and annual incidence ranged from 0.5% to 14%. Case fatality rates ranged from 7.7% to 23.1%. We found similar annual incidence rates of RSV-positive acute respiratory infection (ARI) of 4582 (95% CI: 3259-6264) and 4785 (95% CI: 2258-10,141) per 100,000 reported in two studies. Annual incidence rate of RSV-positive lower respiratory tract infection was 3040 (95% CI: 1986-4454) cases per 100,000 adults. Annual RSV-ARI hospital admission rates were between 600 (95% CI: 190-10,000) and 1104 (95% CI: 350-1930) per 100,000 person-years. Among all RSV disease cases, commonly reported chronic medical conditions included chronic obstructive pulmonary disease (COPD), heart failure, ischemic heart disease, coronary artery disease, hypertension, diabetes, kidney dysfunction, cerebrovascular accident, malignancies, dementia, and those with a Charlson comorbidity score > 6.5.

CONCLUSION

Data on RSV infection among NCH residents are limited and largely heterogeneous but document a high risk of illness, frequent hospitalization, and high mortality. Preventive interventions, such as vaccination, should be considered for this high-risk population. Nationally representative epidemiologic studies and NCH-based viral pathogen surveillance could more precisely assess the burden on NCH residents.

Adult Respiratory Syncytial Virus Infection: Defining Incidence, Risk Factors for Hospitalization, and Poor Outcomes, a Regional Cohort Study, 2016-2022

BACKGROUND

Respiratory syncytial virus (RSV) is a significant cause of illness in adults, especially older adults and those with underlying conditions. This study aimed to assess the incidence of RSV hospitalizations in adults and identify risk factors for hospitalization and poor outcomes.

METHODS

A retrospective cohort study was conducted using data from two hospitals in southern Israel from 2016-2022. We calculated incidence rates of RSV and influenza hospitalizations. Risk factors for hospitalization were analyzed using Poisson regression. We evaluated poor outcomes (death, ICU admission, or mechanical ventilation) among RSV-hospitalized patients.

RESULTS

The median annual incidence of RSV hospitalization was 28.2/100,000 population, increasing with age to 199/100,000 in those ≥75 years. Significant risk factors for RSV hospitalization included pulmonary diseases (RR 4.2, 95% CI 3.4-5.2), cardiovascular diseases (RR 3.3, 95% CI 2.6-4.2), and chronic renal failure (RR 2.9, 95% CI 2.3-3.7). Among hospitalized RSV patients, 13.9% had poor outcomes. Renal failure (RR 1.81, 95% CI 1.23-2.66), neutropenia (RR 2.53, 95% CI 1.19-5.35), neutrophilia (RR 1.66, 95% CI 1.81-2.34), and lymphopenia (RR 2.03, 95% CI 1.37-3.0) were associated with poor outcomes.

CONCLUSIONS

RSV causes a substantial burden of hospitalizations in adults, particularly among older adults and those with comorbidities. Identifying high-risk groups can help target prevention and treatment strategies, including vaccination.

Burden of respiratory syncytial virus (RSV) infection in Germany: a systematic review

BACKGROUND

Respiratory syncytial virus (RSV) is a major cause of acute lower respiratory infection and hospitalizations among infants, young children, and the elderly. This systematic literature review aimed to summarize the epidemiological and economic burden estimates of RSV infection at any age in Germany.

METHODS

We conducted a systematic literature search to identify full-text articles published from 2003 to 2023 and reporting data on the epidemiological or economic burden of RSV in Germany. Based on pre-specified eligibility criteria, data on incidence, rates of hospital and intensive care unit (ICU) admission, clinical manifestation, underlying conditions, seasonality, health care resource use and costs were extracted.

RESULTS

After screening 315 full-text articles, we included 42 articles in the review. The characteristics of the included studies were heterogenous regarding study population, setting, age groups and RSV-related outcome measures. The most frequently reported epidemiological outcome measures were RSV detection rate (n = 33), followed by clinical manifestation (n = 19), seasonality (n = 18), and underlying conditions of RSV infection (n = 13). RSV detection rates were reported across heterogenous study populations, ranging from 5.2 to 55.4% in pediatric inpatient cases and from 2.9 to 14% in adult inpatient cases. All articles that reported RSV detection rates across several age groups demonstrated the highest burden in infants and young children. Few articles reported RSV-related outcome measures distinctively for the outpatient setting. Health care resource use, such as hospital length of stay, ICU admission rate and treatment of patients with RSV infection were described in 23 articles, of which only one study quantified associated costs from 1999 to 2003 for children ≤ 3 years. In-hospital ICU admission rates varied between 3.6 and 45%, depending on population characteristics as age and underlying conditions.

CONCLUSIONS

This systematic review revealed that RSV imposes substantial disease burden in infants, young children, and the elderly in Germany, whereby infants are particularly affected. To date, there has been limited exploration of the impact of RSV infection on healthy children or the elderly in Germany. Given their notably high reported burden in studies, the medical and economic RSV burden in these groups should move more into focus.

Burden of Disease Due to Respiratory Syncytial Virus in Adults in Five Middle-Income Countries

Respiratory syncytial virus (RSV) is an important cause of severe respiratory disease in older adults. Understanding the disease burden is crucial for guiding vaccination policy and raising disease awareness. We estimated the burden of RSV hospitalizations and deaths in adults in five middle-income countries: Argentina, Brazil, Chile, Mexico, and Malaysia. Hospital discharge and death statistics due to any respiratory disease (ICD-10 codes: J00-99) from 2010 to 2022 were obtained. The RSV attributable burden on hospitalizations and deaths by age group was determined for 2019 using previously published estimates. Latin American countries showed distinct annual peaks in respiratory-related hospitalizations and deaths during winter months that were absent in Malaysia. Among ≥20-year-olds in 2019, there were 14,604 RSV-attributable hospitalizations nationally in Argentina, 44,323 in Brazil, 4529 in Chile, 7416 in Malaysia, and 8651 in Mexico, and 60-74% in ≥65-year-olds. There were also 3518 RSV-attributable deaths in Argentina, 9115 in Brazil, 801 in Chile, 704 in Malaysia, and 3806 in Mexico 79-88% in ≥65-year-olds. Incidences of RSV-attributable hospitalizations in ≥75-year-olds ranged between 256.3 and 294.3 per 100,000 population, and deaths between 33.6 and 112.9 per 100,000 population. RSV is associated with a substantial disease burden beyond pediatric age groups, and preventive vaccines could have a major impact on this burden, especially in older adults.

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.

Impact of Nirsevimab Immunization on Pediatric Hospitalization Rates: A Systematic Review and Meta-Analysis (2024)

A systematic review with a meta-analysis was performed to gather available evidence on the effectiveness of monoclonal antibody nirsevimab in the prevention of lower respiratory tract diseases (LRTDs) due to respiratory syncytial virus (RSV) in children and newborns (CRD42024540669). Studies reporting on real-world experience and randomized controlled trials (RCTs) were searched for in three databases (PubMed, Embase, and Scopus) until 1 May 2024. Our analysis included five RCTs, seven real-world reports, and one official report from the health authorities. Due to the cross-reporting of RCTs and the inclusion of multiple series in a single study, the meta-analysis was performed on 45,238 infants from 19 series. The meta-analysis documented a pooled immunization efficacy of 88.40% (95% confidence interval (95% CI) from 84.70 to 91.21) on the occurrence of hospital admission due to RSV, with moderate heterogeneity (I2 24.3%, 95% CI 0.0 to 56.6). Immunization efficacy decreased with the overall length of the observation time (Spearman's r = -0.546, p = 0.016), and the risk of breakthrough infections was substantially greater in studies with observation times ≥150 days compared to studies lasting <150 days (risk ratio 2.170, 95% CI 1.860 to 2.532). However, the effect of observation time in meta-regression analysis was conflicting (β = 0.001, 95% CI -0.001 to 0.002; p = 0.092). In conclusion, the delivery of nirsevimab was quite effective in preventing hospital admissions due to LRTDs. However, further analyses of the whole RSV season are required before tailoring specific public health interventions.

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.

Respiratory Syncytial Virus (RSV) Hospitalizations in the Elderly in a Tertiary Care Hospital in Southern Italy as a Useful Proxy for Targeting Vaccine Preventive Strategies

RSV infection causes severe respiratory illness and mortality in the elderly, especially in the presence of comorbidities. Early identification of infection would result in appropriate clinical-therapeutic management, avoiding hospitalizations, the risk of healthcare-associated infections, and inappropriate antibiotic prescriptions, thus reducing healthcare costs and fighting antimicrobial resistance. The aim of this study was to assess RSV hospitalizations in subjects >64 years hospitalized in a large tertiary care hospital in Southern Italy, in order to assess their usefulness as a proxy for targeting a potential vaccination strategy. Fifty-two RSV-positive patients were identified from the 2014-2015 to the 2022-2023 seasons. RSV type B was found in 71.2% of cases. The median age was 78 years (IQR: 72-84) and 40.4% of the subjects had at least one comorbidity; 5.8% needed intensive care. The use of combined rapid tests for SARS-CoV-2/influenza/RSV identification in primary care settings may contribute to an improved definition of the burden of RSV in the elderly. The implementation of an anti-RSV vaccination strategy in the elderly population would reduce direct and indirect infection costs. More robust epidemiological data in Italy are needed for targeted preventive strategies.

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.

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.

The disease burden of respiratory syncytial virus in older adults

PURPOSE OF REVIEW

To highlight the respiratory syncytial virus (RSV) disease burden and the current developments and challenges in RSV prevention for older adults ≥60 years through analysis of RSV epidemiology and the effectiveness of emerging vaccines.

RECENT FINDINGS

In industrialized countries, RSV incidence rates and hospitalization rates among older adults are estimated to be 600.7 cases per 100 000 person-years and 157 hospitalizations per 100 000 person-years, respectively. Yet, accurately determining RSV morbidity and mortality in older adults is challenging, thus resulting in substantially under-estimating the disease burden. The in-hospital fatality rates vary substantially with age and geographies, and can be as high as 9.1% in developing countries. Two promising RSV vaccines for the elderly have been approved, demonstrating efficacies of up to 94.1%, signifying considerable advancement in RSV prevention. However, concerns over potential side effects remain.

SUMMARY

RSV is associated with a significant burden in older adults. While the landscape of RSV prevention in older adults is promising with the licensure of vaccines from two companies, current trial data underscore the need for additional studies. Addressing the real-world effectiveness of these vaccines, understanding potential rare side effects, and ensuring broad inclusivity in future trials are crucial steps to maximize their potential benefits.

Estimated Incidence of Hospitalizations and Deaths Attributable to Respiratory Syncytial Virus Infections Among Adults in Germany Between 2015 and 2019

INTRODUCTION

Respiratory syncytial virus (RSV) burden in adults is underestimated mainly due to unspecific symptoms and limited standard-of-care testing. We estimated the population-based incidence of hospitalization and mortality attributable to RSV among adults with and without risk factors in Germany.

METHODS

Weekly counts of hospitalizations and deaths for respiratory, cardiovascular, and cardiorespiratory diseases were obtained (Statutory Health Insurance database, 2015-2019). A quasi-Poisson regression model was fitted to estimate the number of hospitalizations and deaths attributable to RSV as a function of periodic and aperiodic time trends, and viral activity while allowing for potential overdispersion. Weekly counts of RSV and influenza hospitalizations in children < 2 years and adults ≥ 60 years, respectively, were used as viral activity indicators. Models were stratified by age group and risk status (defined as presence of selected comorbidities).

RESULTS

Population-based RSV-attributable hospitalization incidence rates were high among adults ≥ 60 years: respiratory hospitalizations (236-363 per 100,000 person-years) and cardiorespiratory hospitalizations (584-912 per 100,000 person-years). RSV accounted for 2-3% of all cardiorespiratory hospitalizations in this age group. The increase in cardiorespiratory hospitalization risk associated with underlying risk factors was greater in 18-44 year old persons (five to sixfold higher) than in ≥ 75 year old persons (two to threefold higher).

CONCLUSIONS

This is a first model-based study to comprehensively assess adult RSV burden in Germany. Estimated cardiorespiratory RSV hospitalization rates increased with age and were substantially higher in people with risk factors compared to those without risk factors. Our study indicates that RSV, like other respiratory viruses, contributes to both respiratory and cardiovascular hospitalizations. Effective prevention strategies are needed, especially among older adults ≥ 60 years and among adults with underlying risk factors.

From Forgotten Pathogen to Target for New Vaccines: What Clinicians Need to Know about Respiratory Syncytial Virus Infection in Older Adults

Respiratory syncytial virus (RSV) is increasingly recognized as being implicated in acute illness in older adults, with a significant weight in hospitalizations for respiratory illness and death. By means of a best-evidence review, this paper aims to investigate whether RSV can be considered a forgotten pathogen in older patients, looking at trends in the literature volume and exploring possible epidemiological and clinical features underlying the focus given to it. We then present an assessment of its disease burden and present and future strategies for its reduction, particularly in light of the recent availability of new vaccines.

Epidemiology and burden of respiratory syncytial virus in Italian adults: A systematic review and meta-analysis

OBJECTIVE

Respiratory syncytial virus (RSV) is a common respiratory pathogen not only in children, but also in adults. In view of a recent authorization of adult RSV vaccines in Italy, our research question was to quantify the epidemiology and burden of RSV in Italian adults.

METHODS

Observational studies on the epidemiology and clinical burden of laboratory-confirmed or record-coded RSV infection in Italian adults of any age were eligible. Studies with no separate data for Italian adults, modeling and other secondary publications were excluded. A literature search was performed in MEDLINE, Biological Abstracts, Global Health, Scopus and Web of Science on 22 November 2023. Critical appraisal was performed by means of a Joanna Briggs Institute checklist. Random-effects (RE) meta-analysis was performed to obtain pooled estimates and the observed heterogeneity was investigated by subgroup and meta-regression analyses. The protocol was prospectively registered (doi.org/10.17504/protocols.io.5qpvo32odv4o/v1).

RESULTS

Thirty-five studies were identified, most of which had at least one possible quality concern. RSV seasonal attack rates ranged from 0.8 ‰ in community-dwelling older adults to 10.9% in hematological outpatients. In the RE model, 4.5% (95% CI: 3.2-5.9%) of respiratory samples tested positive for RSV. This positivity prevalence was higher in older adults (4.4%) than in working-age adults (3.5%) and in outpatient (4.9%) than inpatient (2.9%) settings. According to the meta-regression, study location and sample size were also significant predictors of RSV detection frequency. The pooled estimate of in-hospital mortality was as high as 7.2% (95% CI: 4.7-10.3%). Data on other indicators of the diseases burden, such as complication and hospitalization rates, were unavailable.

CONCLUSION

RSV poses a measurable burden on Italian adults, especially those of older age and with some co-morbidities. However, several data on the natural history of RSV disease are missing and should be established by future large-scale studies.

Respiratory Syncytial Virus-Associated Hospitalization in Adults With Comorbidities in 2 European Countries: A Modeling Study

BACKGROUND

Individuals with comorbidities are at increased risk of severe respiratory syncytial virus (RSV) infection. We estimated RSV-associated respiratory hospitalization among adults aged ≥45 years with comorbidities in Denmark and Scotland.

METHODS

By analyzing national hospital and virologic data, we estimated annual RSV-associated hospitalizations by 7 selected comorbidities and ages between 2010 and 2018. We estimated rate ratios of RSV-associated hospitalization for adults with comorbidity than the overall population.

RESULTS

In Denmark, annual RSV-associated hospitalization rates per 1000 adults ranged from 3.1 for asthma to 19.4 for chronic kidney disease (CKD). In Scotland, rates ranged from 2.4 for chronic liver disease to 9.0 for chronic obstructive pulmonary disease (COPD). In both countries, we found a 2- to 4-fold increased risk of RSV hospitalization for adults with COPD, ischemic heart disease, stroke, and diabetes; a 1.5- to 3-fold increased risk for asthma; and a 3- to 7-fold increased risk for CKD. RSV hospitalization rates among adults aged 45 to 64 years with COPD, asthma, ischemic heart disease, or CKD were higher than the overall population.

CONCLUSIONS

This study provides important evidence for identifying risk groups and assisting health authorities in RSV vaccination policy making.

Respiratory Syncytial Virus-Associated Hospital Admissions by Deprivation Levels Among Children and Adults in Scotland

BACKGROUND

Socioeconomic deprivation may predispose individuals to respiratory tract infections. We estimated RSV-associated hospitalizations by socioeconomic deprivation in Scotland.

METHODS

Using national routine health care records and virological surveillance from 2010 to 2016, we used a time-series linear regression model and a direct measurement based on ICD-10 coded diagnoses to estimate RSV-associated hospitalizations by Scottish Index of Multiple Deprivation (SIMD) quintile and age in comparison to influenza-associated hospitalizations.

RESULTS

We estimated an annual average rate per 1000 people of 0.76 (95% CI: 0.43-0.90) in the least deprived group to 1.51 (1.03-1.79) for the most deprived group using model-based approach. The rate ratio (RR) was 1.96 (1.23-3.25), 1.60 (1.0-2.66), 1.35 (0.85-2.25), and 1.12 (0.7-1.85) in the 1st to 4th quintile versus the least deprived group. The pattern of RSV-associated hospitalization rates variation with SIMD was most pronounced in children 0-2y. The ICD-10 approach provided much lower rates than the model-based approach but yielded similar RR estimates between SIMD. Influenza-associated hospitalization rate generally increased with higher deprivation levels among individuals 1y+.

CONCLUSIONS

Higher RSV and influenza hospitalization rates are related to higher deprivation levels. Differences between deprivation levels are most pronounced in infants and young children for RSV, and are more apparent among individuals 1y+ for influenza.

Respiratory Syncytial Virus Vaccination Recommendations for Adults Aged 60 Years and Older: The NeumoExperts Prevention Group Position Paper

Respiratory syncytial virus (RSV) is a major cause of respiratory tract infections in adults, particularly older adults and those with underlying medical conditions. Vaccination has emerged as a potential key strategy to prevent RSV-related morbidity and mortality. This Neumoexperts Prevention (NEP) Group scientific paper aims to provide an evidence-based positioning and RSV vaccination recommendations for adult patients. We review the current literature on RSV burden and vaccine development and availability, emphasising the importance of vaccination in the adult population. According to our interpretation of the data, RSV vaccines should be part of the adult immunisation programme, and an age-based strategy should be preferred over targeting high-risk groups. The effectiveness and efficiency of this practice will depend on the duration of protection and the need for annual or more spaced doses. Our recommendations should help healthcare professionals formulate guidelines and implement effective vaccination programmes for adult patients at risk of RSV infection now that specific vaccines are available.

Respiratory Syncytial Virus (RSV) and Intention to Recommend RSV Vaccination: A Cross-Sectional Survey of Cardiologists and Cardiac Nurses in Southern Italy

As respiratory syncytial virus (RSV) vaccine distribution gains traction in Europe and Italy, healthcare workers (HCWs) can strategize about vaccine promotion to increase uptake among patients at risk of RSV consequences, such cardiac patients. This cross-sectional survey investigated the knowledge about and attitude towards RSV and RSV vaccines, and the intention to recommend vaccination within a cardiological hospital in Italy. To explore factors associated with the outcomes of interest, multivariate logistic regression analyses were conducted. Of 197 invited HCWs, 78.2% returned the survey. The knowledge about market authorisation for new RSV vaccines for older adults (present in 46.9% of respondents) was significantly associated with the HCWs' age, education, and previous update on vaccinations. HCWs with a higher educational level and those with a positive attitude towards RSV vaccines safety reported a higher attitude towards the importance of vaccinating people at risk. The willingness of recommending RSV vaccination to patients (70.5% of respondents) was more likely in HCWs who were knowledgeable about market authorisation for RSV vaccines and in physicians. This tempestive research sheds light on current factors influencing the strategies of cardiac HCWs regarding RSV vaccination. The results suggest the need for training events on the protective role of RSV vaccination in cardiac patients.

Respiratory Syncytial Virus, Influenza and SARS-CoV-2 in Homeless People from Urban Shelters: A Systematic Review and Meta-Analysis (2023)

Homeless people (HP) are disproportionally affected by respiratory disorders, including pneumococcal and mycobacterial infections. On the contrary, more limited evidence has been previously gathered on influenza and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and very little is known about the occurrence of human respiratory syncytial virus (RSV), a common cause of respiratory tract infections among children and the elderly. The present systematic review was designed to collect available evidence about RSV, influenza and SARS-CoV-2 infections in HP, focusing on those from urban homeless shelters. Three medical databases (PubMed, Embase and Scopus) and the preprint repository medRxiv.org were therefore searched for eligible observational studies published up to 30 December 2023, and the collected cases were pooled in a random-effects model. Heterogeneity was assessed using the I2 statistics. Reporting bias was assessed by funnel plots and a regression analysis. Overall, 31 studies were retrieved, and of them, 17 reported on the point prevalence of respiratory pathogens, with pooled estimates of 4.91 cases per 1000 HP (95%CI: 2.46 to 9.80) for RSV, 3.47 per 1000 HP for influenza and 40.21 cases per 1000 HP (95%CI: 14.66 to 105.55) for SARS-CoV-2. Incidence estimates were calculated from 12 studies, and SARS-CoV-2 was characterized by the highest occurrence (9.58 diagnoses per 1000 persons-months, 95%CI: 3.00 to 16.16), followed by influenza (6.07, 95%CI: 0.00 to 15.06) and RSV (1.71, 95%CI: 0.00 to 4.13). Only four studies reported on the outcome of viral infections in HP: the assessed pathogens were associated with a high likelihood of hospitalization, while high rates of recurrence and eventual deaths were reported in cases of RSV infections. In summary, RSV, influenza and SARS-CoV-2 infections were documented in HP from urban shelters, and their potential outcomes stress the importance of specifically tailored preventive strategies.