Disease burden caused by respiratory syncytial virus compared with influenza among adults: a retrospective cohort study from Eastern Finland in 2017-2018

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.

Burden of Respiratory Syncytial Virus Disease in Adults with Asthma and Chronic Obstructive Pulmonary Disease: A Systematic Literature Review

PURPOSE OF REVIEW

Accumulating data indicate that asthma and chronic obstructive pulmonary disease (COPD) increase the risk of severe respiratory syncytial virus (RSV) infection. This systematic literature review assessed the burden of RSV disease among adults ≥ 18 years with asthma or COPD.

RECENT FINDINGS

Data on the prevalence of asthma or COPD among RSV-infected adults, RSV-related hospitalizations, complications, and mortality were collected from studies published between January 1, 2000 and November 28, 2023 in PubMed, Embase, and grey literature. All extracted data were analyzed descriptively. Pooled estimates of asthma or COPD prevalence among RSV-infected adults were calculated from generalized linear mixed effects model meta-analyses. Forty studies were included. The prevalence of asthma and COPD among RSV-infected adults was high, especially in inpatient settings with pooled estimates (95% confidence interval) of 19.3% (15.0-24.6) for asthma and 30.8% (26.1-36.0) for COPD. Adults with asthma or COPD were more likely to be hospitalized following RSV infection than those without these conditions. The incidence rate ratios of hospitalization were 2.0-3.6 (crude) and 6.7-8.2 (adjusted) for asthma and 3.2-13.4 (crude) and 9.6-9.7 (adjusted) for COPD. The most frequently reported RSV-related complications were exacerbation of asthma (up to 64.9%) and COPD (up to ≥ 83.0%). In-hospital case fatality rates were 2.6-4.3% (asthma) and 2.8-17.8% (COPD). These comprehensive data showing a high RSV disease burden in adults with asthma or COPD can be used to inform policy decisions around RSV vaccines and improve preventive care in this high-risk population.

Comparison of clinical characteristics and outcomes in hospitalized adult patients infected with respiratory syncytial virus and influenza virus

BACKGROUND

Because patients infected with respiratory syncytial virus (RSV) have been reported to be older than patients infected with influenza virus, the more frequent incidence of complications in RSV-infected patients may be age-related. This study compared clinical characteristics and outcomes in hospitalized adults infected with RSV with findings in age- and sex-matched adults infected with influenza virus.

METHODS

The medical records of hospitalized adult patients infected with RSV or influenza virus at two university hospitals from 2013 to 2022 were retrospectively analyzed. Virus infection was confirmed by real-time polymerase chain reaction. Each RSV-infected patient was matched by age and sex with two influenza virus-infected patients, and their clinical symptoms, laboratory parameters and hospital courses were compared.

RESULTS

The study cohort consisted of 552 patients, 184 infected with RSV and 368 infected with influenza virus. Fever (71.2% vs. 79.9%, p = .022) and cough (70.1% vs. 80.4%, p = .007) were significantly less frequent in the RSV than in the influenza group, whereas white blood cell counts (9132/mm3 vs. 7616/mm3, p < .001) and C-reactive protein concentrations (10.25 vs. 8.88 mg/dL, p = .029) were significantly higher in the RSV group. The frequency of oxygen therapy was higher (60.3% vs. 48.6%, p = .010) and hospital stay was longer (8 vs. 6 days, p = .003) in RSV than in influenza virus-infected patients.

CONCLUSIONS

Clinical symptoms were less frequent, but disease was more severe, in hospitalized adult patients infected with RSV than in age- and sex-matched patients infected with influenza. Greater attention should be paid to diagnosing and preventing RSV infection in adults.

Respiratory syncytial virus: Characteristics, complications and mortality in immunocompetent versus immunocompromised hospitalized adults in Northern Denmark

BACKGROUND

Respiratory syncytial virus (RSV) is an increasingly well-known cause of severe respiratory symptoms in adults. We aimed to describe characteristics, complications and in-hospital mortality of adults admitted to hospital with RSV-related respiratory symptoms.

METHODS

Data were collected from electronic health records in the North Denmark Region for hospitalized adults diagnosed with RSV between April 1st - December 31st 2021. We collected data on characteristics, complications and mortality. Results were compared between immunocompromised and -competent patients.

RESULTS

We included 111 patients. Sixty-five percent had comorbidities and 20 % received immunosuppressive drugs. Fifty-three percent had bacterial pneumonia and 61 % needed oxygen support. Mortality was 12 %. There were no differences in complications between the compared groups.

CONCLUSION

Severe respiratory symptoms were frequent among RSV-patients. Bacterial co-infections were common in the study population and mortality was considerable, regardless of known immunosuppression, thus warranting thorough and early investigations in RSV-positive patients.

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.

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.

Predictors of prolonged length of stay in adult patients with respiratory syncytial virus infections - a multi-center historical cohort study

Objectives

Several studies have reported risk factors for severe disease and mortality in hospitalized adults with RSV infections. There is limited information available regarding the factors that affect the duration of a patient's hospital length of stay (LOS).

Methods

This was a multicenter historical cohort study of adult patients hospitalized for laboratory-confirmed RSV in Southeast Michigan between January 2017 and December 2021. Hospitalized patients were identified using the International Classification of Diseases, Tenth Revision 10 codes for RSV infection. Mean LOS was computed; prolonged LOS was defined as greater than the mean.

Results

We included 360 patients with a mean age (SD) of 69.9 ± 14.7 years, 63.6% (229) were female and 63.3% (228) of white race. The mean hospital LOS was 7.1 ± 5.4 days. Factors associated with prolonged LOS in univariable analysis were old age, body mass index (BMI), smoking status, Charlson Weighted Index of Comorbidity (CWIC), home oxygen, abnormal chest x-ray (CXR), presence of sepsis, use of oxygen, and antibiotics at the time of presentation. Predictors for prolonged LOS on admission in multivariable analysis were age on admission (p < 0.001), smoking status (p = 0.001), CWIC (p = 0.038) and abnormal CXR (p = 0.043).

Interpretation

Our study found that age on admission, smoking history, higher CWIC and abnormal CXR on admission were significantly associated with prolonged LOS among adult patients hospitalized with RSV infection. These findings highlight the significance of promptly recognizing and implementing early interventions to mitigate the duration of hospitalization for adult patients suffering from RSV infection.

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.

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 Prefusion F Protein Vaccine Is Efficacious in Older Adults With Underlying Medical Conditions

BACKGROUND

Older adults with chronic cardiorespiratory or endocrine/metabolic conditions are at increased risk of respiratory syncytial virus (RSV)-related acute respiratory illness (RSV-ARI) and severe respiratory disease. In an ongoing, randomized, placebo-controlled, multicountry, phase 3 trial in ≥60-year-old participants, an AS01E-adjuvanted RSV prefusion F protein-based vaccine (RSVPreF3 OA) was efficacious against RSV-related lower respiratory tract disease (RSV-LRTD), severe RSV-LRTD, and RSV-ARI. We evaluated efficacy and immunogenicity among participants with coexisting cardiorespiratory or endocrine/metabolic conditions that increase the risk of severe RSV disease ("conditions of interest").

METHODS

Medically stable ≥60-year-old participants received 1 dose of RSVPreF3 OA or placebo. Efficacy against first RSV-LRTD and RSV-ARI episodes was assessed in subgroups with/without coexisting cardiorespiratory or endocrine/metabolic conditions of interest. Immunogenicity was analyzed post hoc in these subgroups.

RESULTS

In total, 12 467 participants received RSVPreF3 OA and 12 499 received placebo. Of these, 39.6% (RSVPreF3 OA) and 38.9% (placebo) had ≥1 coexisting condition of interest. The median efficacy follow-up was 6.7 months. Efficacy against RSV-LRTD was high in participants with ≥1 condition of interest (94.6%), ≥1 cardiorespiratory (92.1%), ≥1 endocrine/metabolic (100%), and ≥2 conditions of interest (92.0%). Efficacy against RSV-ARI was 81.0% in participants with ≥1 condition of interest (88.1% for cardiorespiratory, 79.4% for endocrine/metabolic conditions) and 88.0% in participants with ≥2 conditions of interest. Postvaccination neutralizing titers were at least as high in participants with ≥1 condition of interest as in those without.

CONCLUSIONS

RSVPreF3 OA was efficacious against RSV-LRTD and RSV-ARI in older adults with coexisting medical conditions associated with an increased risk of severe RSV disease.

CLINICAL TRIALS REGISTRATION

ClinicalTrials.gov: NCT04886596.

Comparative analysis of clinical features of lower respiratory tract infection with respiratory syncytial virus and influenza virus in adults: a retrospective study

BACKGROUND

Respiratory syncytial virus (RSV) infection in adults remains less recognized and understood, both socially and clinically, compared to influenza virus infection. This retrospective study aims to delineate and compare the clinical manifestations of adult RSV and influenza virus infections in the lower respiratory tract, thereby enhancing awareness of RSV lower respiratory tract infection and providing strategic insights for its prevention and treatment.

METHODS

Clinical data from January 2019 to December 2020 were analyzed for 74 patients with RSV and 129 patients with influenza A/B virus lower respiratory tract infections who were admitted to respiratory or intensive care units. All patients had complete clinical data with positive IgM and negative IgG viral antibodies. Comparison parameters included onset timing, baseline data, clinical manifestations, supplementary examination results, treatment methods, and prognosis, while logistic regression was employed to ascertain the correlation of clinical features between the two patient groups.

RESULTS

In comparison to the influenza group, the RSV group presented less frequently with fever at admission but exhibited a higher incidence of dyspnea and wheezing on pulmonary auscultation (P < 0.01). RSV infection was more prevalent among patients with underlying diseases, particularly chronic obstructive pulmonary disease (COPD) and demonstrated a higher probability of co-infections, most notably with Mycoplasma (P < 0.01). The RSV group had significantly higher lymphocyte counts (P < 0.01) and exhibited more incidences of pleural thickening, pulmonary fibrosis, and emphysema (P < 0.05). The use of non-invasive mechanical ventilation was more common, and hospital stays were longer in the RSV group compared to the influenza group (P < 0.05). Logistic multivariate regression analysis further revealed that age and tachypnea incidence were significantly higher in the RSV group (P < 0.05).

CONCLUSION

Compared to influenza virus infection, adults with COPD are more susceptible to RSV infection. Moreover, RSV infection elevates the risk of co-infection with Mycoplasma and may lead to conditions such as pleural thickening, pulmonary fibrosis, and emphysema. The requirement for non-invasive mechanical ventilation is higher in RSV-infected patients, who also tend to have longer hospital stays. Therefore, greater awareness and preventive strategies against RSV infection are imperative.

Resurgence of influenza and respiratory syncytial virus in Egypt following two years of decline during the COVID-19 pandemic: outpatient clinic survey of infants and children, October 2022

INTRODUCTION

Two years after unprecedented low rates of circulation of most common respiratory viruses (SARS-CoV-2), the Egyptian ARI surveillance system detected an increase in acute respiratory infections (ARIs) with a reduced circulation of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), especially among school children. A national survey was conducted to estimate the burden and identify the viral causes of ARIs among children < 16 years of age.

METHODS

A one-day survey was carried out in 98 governmental outpatient clinics distributed all over Egypt 26 governorates. The four largest referral hospitals in each governorate where most influenza-like illness (ILI) patients seek care were selected. Using the WHO case definition, the first five patients < 16 years of age with ILI symptoms visiting the selected outpatient clinics on the survey day were enrolled. Basic demographic and clinical data of patients were collected using a linelist. Patients were swabbed and tested for SARS-CoV-2, influenza, and Respiratory Syncytial virus (RSV) by RT-PCR at the Central Laboratory in Cairo.

RESULTS

Overall, 530 patients enrolled, their mean age was 5.8 ± 4.2, 57.1% were males, and 70.2% reside in rural or semi-rural areas. Of all patients, 134 (25.3%) had influenza, 111 (20.9%) RSV, and 14 (2.8%) coinfections. Influenza-positive children were older compared to RSV, (7.2 ± 4.1, 4.3 ± 4.1, p < 0.001), with more than half of them (53.0%) being school students. Dyspnea was reported in RSV more than in influenza (62.2% vs. 49.3%, p < 0.05). Among RSV patients, children < 2 years had a higher rate of dyspnea than others (86.7% vs. 53.1%, < 0.001).

CONCLUSIONS

A resurgence of influenza and RSV was detected in Egypt in the 2022-2023 winter season. Influenza caused a higher rate of infection than RSV, while RSV caused more severe symptoms than influenza. Monitoring a broader range of respiratory pathogens is recommended to estimate the ARI burden and risky groups for severe disease in Egypt.

Respiratory syncytial virus infection in the modern era

PURPOSE OF REVIEW

Respiratory syncytial virus (RSV) continues to be a major cause of severe lower respiratory tract infection in infants, young children, and older adults. In this review, changes in the epidemiology of RSV during the coronavirus disease 2019 (COVID-19) pandemic are highlighted together with the role which increased molecular surveillance efforts will have in future in assessing the efficacy of vaccines and therapeutics.

RECENT FINDINGS

The introduction of nonpharmaceutical intervention (NPIs) strategies during the COVID-19 pandemic between 2020 and 2022 resulted in worldwide disruption to the epidemiology of RSV infections, especially with respect to the timing and peak case rate of annual epidemics. Increased use of whole genome sequencing along with efforts to better standardize the nomenclature of RSV strains and discrimination of RSV genotypes will support increased monitoring of relevant antigenic sites in the viral glycoproteins. Several RSV vaccine candidates based on subunit, viral vectors, nucleic acid, or live attenuated virus strategies have shown efficacy in Phase 2 or 3 clinical trials with vaccines using RSVpreF protein currently the closest to approval and use in high-risk populations. Finally, the recent approval and future use of the extended half-life human monoclonal antibody Nirsevimab will also help to alleviate the morbidity and mortality burden caused by annual epidemics of RSV infections.

SUMMARY

The ongoing expansion and wider coordination of RSV molecular surveillance efforts via whole genome sequencing will be crucial for future monitoring of the efficacy of a new generation of vaccines and therapeutics.