Risk of Severe Influenza Among Adults With Chronic Medical Conditions

The Impact of Vaccination on COVID-19, Influenza, and Respiratory Syncytial Virus-Related Outcomes: A Narrative Review

Vaccination represents a core preventive strategy for public health, with interrelated and multifaceted effects across health and socioeconomic domains. Beyond immediate disease prevention, immunization positively influences downstream health outcomes by mitigating complications of preexisting comorbidities and promoting healthy aging. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza virus, and respiratory syncytial virus (RSV) are common respiratory viruses responsible for broad societal cost and substantial morbidity and mortality, particularly among at-risk individuals, including older adults and people with frailty or certain comorbid conditions. In this narrative review, we summarize the overall impact of vaccination for these 3 viruses, focusing on mRNA vaccines, each of which exhibits unique patterns of infection, risk, and transmission dynamics, but collectively represent a target for preventive strategies. Vaccines for COVID-19 (caused by SARS-CoV-2) and influenza are effective against the most severe outcomes, such as hospitalization and death; these vaccines represent the most potent and cost-effective interventions for the protection of population and individual health against COVID-19 and influenza, particularly for older adults and those with comorbid conditions. Based on promising results of efficacy for the prevention of RSV-associated lower respiratory tract disease, the first RSV vaccines were approved in 2023. Immunization strategies should account for various factors leading to poor uptake, including vaccine hesitancy, socioeconomic barriers to access, cultural beliefs, and lack of knowledge of vaccines and disease states. Coadministration of vaccines and combination vaccines, such as multicomponent mRNA vaccines, offer potential advantages in logistics and delivery, thus improving uptake and reducing barriers to adoption of new vaccines. The success of the mRNA vaccine platform was powerfully demonstrated during the COVID-19 pandemic; these and other new approaches show promise as a means to overcome existing challenges in vaccine development and to sustain protection against viral changes over time.A graphical abstract and video abstract is available with this article.

A Narrative Review of Key Risk Factors for Severe Illness Following SARS-CoV-2, Influenza Virus, and Respiratory Syncytial Virus Infection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza, and respiratory syncytial virus (RSV) are highly infectious respiratory viruses that affect people of all ages and are typically associated with mild symptoms and few complications in immunocompetent individuals. However, the risk of severe outcomes (e.g., hospitalization and death) following infection with these respiratory viruses is higher in certain populations, including older adults and individuals of certain race/ethnic and sociodemographic groups. Additionally, immunocompromising conditions and pre-existing comorbidities, including underlying cardiovascular (e.g., congestive heart failure) and respiratory diseases (e.g., chronic obstructive pulmonary disease), diabetes, chronic kidney disease, and obesity, are key factors that predispose individuals to SARS-CoV-2-, influenza-, and RSV-related severe outcomes. Increased risk for severe outcomes associated with advancing age and comorbidities is compounded by residence in long-term care facilities due to the enhanced spread of respiratory infections in congregate living environments. In this narrative review, risk factors associated with severe outcomes following infection with SARS-CoV-2, influenza, and RSV in adult populations are explored. Additionally, distinct clinical outcomes based on underlying comorbidities following infection are discussed in the context of high-risk populations. Factors unique to each virus that underpin distinct risk profiles are described and suggest the potential for tailored surveillance and healthcare approaches to target and ultimately mitigate SARS-CoV-2-, influenza-, and RSV-associated disease burden in vulnerable populations. Mutual risk factors for severe outcomes are also highlighted; these similarities indicate that cohesive risk reduction strategies may also be feasible, particularly since vaccines are available for each of these respiratory viruses. Ultimately, a more thorough understanding of the risk factors that predispose individuals to develop SARS-CoV-2-, influenza-, and RSV-related severe outcomes may improve risk reduction strategies, inform healthcare policy, and contribute to the expansion and refinement of existing surveillance approaches to ultimately mitigate disease burden in vulnerable populations.

People with long-term conditions are more adherent to protective behaviours against infectious disease

Objectives

To investigate the relationship between long-term condition (LTC) status and adherence to protective behaviours against infectious disease (face covering, physical distancing, hand hygiene).

Study design

Representative cross-sectional observational survey in summer 2020 in Scotland.

Methods

Independent variable is LTC status (LTC, disability, no LTC); dependent variable is adherence to protective behaviours (face covering, hand hygiene, social distancing); moderator variables are age, gender and area deprivation; mediator variables are perceived threat and psychological distress. P values of p < 0.05 were taken as statistically significant.

Results

3972 participants of whom 2696 (67.9 %) indicated not having a LTC. People with no LTC had lowest adherence to protective behaviours, perceived threat and psychological distress. Age did not moderate the relationship between LTC status and adherence; females were more adherent than males and this gender difference was greater in people with disability compared to people with no LTC; adherence was greater for people with a LTC in the more deprived areas compared to the least deprived areas whereas adherence in those with no LTC was not related to area deprivation; threat appraisal partially mediated the relationship between having a LTC or disability and adherence; psychological distress did not mediate the relationship between LTC status and adherence.

Conclusions

This study addresses a gap in evidence about protective behaviours of people with LTCs. Perceptions of threat may be useful intervention targets against winter flu and during future pandemics in order to protect people with LTCs who are one of the most vulnerable groups of the population.

Secondary healthcare resource utilization and related costs associated with influenza-related hospital admissions in adult patients, England 2016 - 2020

INTRODUCTION

This study aims to investigate healthcare resource utilization and related costs for influenza virus infections in adults admitted into secondary care in England across four influenza seasons.

METHODS

This study includes all influenza admissions from the Hospital Episode Statistics database (HES) across England, September 2016 to March 2020. Descriptive analyses and comparative modeling techniques were used to assess the impact of influenza on risk groups of interest.

RESULTS

Influenza admissions were estimated to cost £401 M. Average admission costs were heavily impacted by age and comorbid status, with comorbid patients representing 91% of costs. Additionally, patients with comorbidities treated in secondary care cost twice as much as non-comorbid patients, after adjusting for age and gender. Comorbid patients also had increased length of stay (LOS) and admissions to ICU, with patients' LOS being a core contributing factor to higher costs.

CONCLUSION

The study documents the substantial burden of influenza in England, emphasizing the impact of age and comorbid status on healthcare resource utilization (HCRU) and related costs. The data presented offers critical information to healthcare systems evaluating new strategies to alleviate the winter pressures on the NHS; highlighting the need to implement vaccination campaigns with enhanced vaccinations and increased vaccine coverage.

Impact of Age and Comorbid Conditions on Incidence Rates of COVID-19-Associated Hospitalizations, 2020-2021

BACKGROUND

COVID-19-associated hospitalization rates by age and comorbid conditions can more precisely assess risk for severe illness and target prevention and treatment strategies.

METHODS

We performed a retrospective study to estimate population-based COVID-19-associated hospitalization among patients by age and selected comorbid conditions in three hospital systems in Rochester and New York City (NYC), NY. Incidence rate ratios (IRR) comparing incidence rates for patients with and without these comorbidities were determined.

RESULTS

From March 2020 to December 2021, 7779 patients were hospitalized with COVID-19 of whom 43.8% had ≥3 comorbid conditions. Overall annual incidence ranged from 325.3 to 965.8 per 100,000 persons. Age group-specific incidence was lowest in children 10-14 years (range 4.4-58.9) and highest in adults ≥85 years (range 2790.5-5889.6). Incidence rates for comorbid conditions generally increased with increasing age while IRR decreased with increasing age. Children in NYC 5-17 years with asthma or obesity had 3.4 and 53.3 times higher hospitalization rates, respectively, than children without these conditions. Adults in all age groups with obesity, diabetes, coronary artery disease, or congestive heart failure CHF had 1.6-4.7 times, 1.7-7.2 times, 2.0-10.1 times, or 1.7-20.2 times higher hospitalization rates, respectively, than those without these conditions. Adults ≥50 years with asthma had 1.5 to 1.8 times higher hospitalization rates than those without asthma.

CONCLUSIONS

The burden of hospitalization with COVID-19 was high, particularly among adults ≥85 years and adults with obesity, diabetes, CAD, or CHF. However, the impact of comorbidities was less in older adults. Population-based incidence rates by age and comorbidities provide more precise estimates of the benefits of vaccines and antiviral medications.

A population-based, province-wide, record-linkage interrupted time series analysis of impact of the universal seasonal influenza vaccination policy on seasonal influenza vaccine uptake among 5-64-year-olds in the province of Manitoba, Canada

INTRODUCTION

Universal seasonal influenza vaccination policy (USIVP) was introduced in Manitoba, Canada in 2010. Its impact on seasonal influenza vaccine (SIV) uptake remains underexplored.

METHODS

We used population-wide data from Manitoba to assess the impact of the USIVP on SIV uptake. The study covered twenty influenza seasons (2000/01-2019/20). We summarized SIV uptake for influenza seasons before and after the USIVP. Utilizing a single-group interrupted time series analysis and appropriately accounting for autocorrelation, we estimated absolute change and annual trend in SIV uptake percentages among 5-17-, 18-44-, and 45-64-year-olds across strata of certain population socioeconomic and health-related characteristics following the USIVP.

RESULTS

Average SIV uptake percentage in all age groups was significantly higher after compared with before the USIVP. Following the USIVP, there was no significant absolute change in SIV uptake percentage among 18-44- and 45-64-year-olds overall; however, a significant decrease was observed among 18-44-year-old males in the higher income quintiles, across healthcare utilization, and in some regions of residence. A significant increase was observed among 5-17-year-olds in the lowest income quintiles, in Northern Manitoba, and among those with less healthcare utilization, and no chronic disease. Overall, there was mostly no significant annual trend in SIV uptake percentage among 18-44-year-olds, and while a significant upward and downward trend was observed among 5-17-year-olds and 45-64-year-olds, respectively, a significant downward trend was observed across all strata of population characteristics within all age groups in Northern Manitoba.

CONCLUSIONS

The USIVP in Manitoba was followed by an absolute increase in SIV uptake percentage only in some socioeconomically disadvantaged subpopulations among 5-17-year-olds. While there was mostly an upward annual trend in SIV uptake percentage among 5-17-year-olds, a downward trend was observed among 45-64-year-olds and across all age groups and subpopulations in socioeconomically disadvantaged Northern Manitoba. These findings are novel for Manitoba and require investigation and public health attention.

Implementation and impact of rapid SARS-CoV-2 point of care test on patient flow in the frailty pathway; A quality improvement approach

To maintain patient flow during the COVID-19 pandemic, rapid and accurate decisions for the safe triage of geriatrics patients was essential as turnaround times for laboratory testing was ineffective at supporting rapid clinical decision-making for transfer of care. Thus, to mitigate and inform these clinical decisions, a quality improvement collaborative project with the geriatrics and virology department was conducted at the Frailty Assessment Unit (FAU) at Aberdeen Royal Infirmary. The goal was to facilitate patient triage during transfer of care with the introduction of Point of Care testing (POCT). The interventions which resulted in significant improvements were based on the fishbone problem solving approach and the driver diagram with change ideas informing the five Plan, Do, Study and Act (PDSA) cycles. The QI intervention was crucial in supporting clinical staff decision making during transfers for 95% of patients who had been clinically judged as asymptomatic for COVID-19 infection. High staff engagement was observed with 83% of staff suggesting the process map was easy to follow and 92% of clinical staff agreed it contained sufficient information to support the testing process. With POCT introduction, the proportion of patients who were transferred with an early POCT result increased by 20% in the Rosewell House group and by 65% in the community Hospitals group, once governance arrangements were in place. Finally, the considerable uptake of POCT by the ward consequently led to a decrease of up to 86% in the number of samples sent to the laboratory for rapid SARS-CoV-2 testing. The quality improvement project provided a rapid and reliable SARS-CoV-2 triage tool and was effectively integrated into the geriatrics triage algorithm to facilitate patient placement and flow.

Influenza vaccine coverage in 6months-64 years-old patients affected by chronic diseases: A retrospective cohort study in Italy

At the beginning of each flu season, the Italian Ministry of Health defines the categories at higher risk of influenza complications, for which vaccination is actively and freely offered. The vaccine coverage (VC) of the influenza vaccine in subjects from 6 months to 64 years of age suffering from diseases that increase the risk of complications from influenza during the 2020-2021 season was evaluated. Our study wants to evaluate the VCs of the influenza vaccine in these subjects during the 2020/2021 season in Apulia. The digital archives relative to the Apulian population were used. A retrospective cohort study design was performed. 484,636 Apulian residents aged between 6 months and 64 years suffered from at least one chronic disease; 139,222 of 484,636 subjects received the influenza vaccine (VC: 28.7%) from October 2020 to January 2021. Considering the single comorbidities, the greatest values are found for pathologies for which major surgical interventions are planned and chronic renal failure/adrenal insufficiency patients, while the worst for chronic liver diseases and pathologies for which major surgical interventions are planned. In any case, it would seem that better VC is achieved in subjects with more than one chronic condition. Influenza vaccination must be promoted as a central public health measure, also because by reducing the burden on hospitals, it can greatly benefit the management of COVID-19 patients. Greater efforts by public health institutions must be implemented in order to achieve better VC in the target categories, including chronic patients.

Association of Chronic Medical Conditions With Severe Outcomes Among Nonpregnant Adults 18-49 Years Old Hospitalized With Influenza, FluSurv-NET, 2011-2019

Background

Older age and chronic conditions are associated with severe influenza outcomes; however, data are only comprehensively available for adults ≥65 years old. Using data from the Influenza Hospitalization Surveillance Network (FluSurv-NET), we identified characteristics associated with severe outcomes in adults 18-49 years old hospitalized with influenza.

Methods

We included FluSurv-NET data from nonpregnant adults 18-49 years old hospitalized with laboratory-confirmed influenza during the 2011-2012 through 2018-2019 seasons. We used bivariate and multivariable logistic regression to determine associations between select characteristics and severe outcomes including intensive care unit (ICU) admission, invasive mechanical ventilation (IMV), and in-hospital death.

Results

A total of 16 140 patients aged 18-49 years and hospitalized with influenza were included in the analysis; the median age was 39 years, and 26% received current-season influenza vaccine before hospitalization. Obesity, asthma, and diabetes mellitus were the most common chronic conditions. Conditions associated with a significantly increased risk of severe outcomes included age group 30-39 or 40-49 years (IMV, age group 30-39 years: adjusted odds ratio [aOR], 1.25; IMV, age group 40-49 years: aOR, 1.36; death, age group 30-39 years: aOR, 1.28; death, age group 40-49 years: aOR, 1.69), being unvaccinated (ICU: aOR, 1.18; IMV: aOR, 1.25; death: aOR, 1.48), and having chronic conditions including extreme obesity and chronic lung, cardiovascular, metabolic, neurologic, or liver diseases (ICU: range aOR, 1.22-1.56; IMV: range aOR, 1.17-1.54; death: range aOR, 1.43-2.36).

Conclusions

To reduce the morbidity and mortality associated with influenza among adults aged 18-49 years, health care providers should strongly encourage receipt of annual influenza vaccine and lifestyle/behavioral modifications, particularly among those with chronic medical conditions.

Frailty and survival in the 1918 influenza pandemic

One of the most well-known yet least understood aspects of the 1918 influenza pandemic is the disproportionately high mortality among young adults. Contemporary accounts further describe the victims as healthy young adults, which is contrary to the understanding of selective mortality, which posits that individuals with the highest frailty within a group are at the greatest risk of death. We use a bioarchaeological approach, combining individual-level information on health and stress gleaned from the skeletal remains of individuals who died in 1918 to determine whether healthy individuals were dying during the 1918 pandemic or whether underlying frailty contributed to an increased risk of mortality. Skeletal data on tibial periosteal new bone formation were obtained from 369 individuals from the Hamann-Todd documented osteological collection in Cleveland, Ohio. Skeletal data were analyzed alongside known age at death using Kaplan-Meier survival and Cox proportional hazards analysis. The results suggest that frail or unhealthy individuals were more likely to die during the pandemic than those who were not frail. During the flu, the estimated hazards for individuals with periosteal lesions that were active at the time of death were over two times higher compared to the control group. The results contradict prior assumptions about selective mortality during the 1918 influenza pandemic. Even among young adults, not everyone was equally likely to die-those with evidence of systemic stress suffered greater mortality. These findings provide time depth to our understanding of how variation in life experiences can impact morbidity and mortality even during a pandemic caused by a novel pathogen.

Safety and immunogenicity of a phase 1/2 randomized clinical trial of a quadrivalent, mRNA-based seasonal influenza vaccine (mRNA-1010) in healthy adults: interim analysis

Despite vaccine availability, influenza remains a substantial global public health concern. Here, we report interim findings on the primary and secondary objectives of the safety, reactogenicity, and humoral immunogenicity of a quadrivalent messenger RNA (mRNA) vaccine against seasonal influenza, mRNA-1010, from the first 2 parts of a 3-part, first-in-human, phase 1/2 clinical trial in healthy adults aged ≥18 years (NCT04956575). In the placebo-controlled Part 1, a single dose of mRNA-1010 (50 µg, 100 µg, or 200 µg) elicited hemagglutination inhibition (HAI) titers against vaccine-matched strains. In the active-comparator-controlled Part 2, mRNA-1010 (25 µg, 50 µg, or 100 µg) elicited higher HAI titers than a standard dose, inactivated seasonal influenza vaccine for influenza A strains and comparable HAI titers for influenza B strains. No safety concerns were identified; solicited adverse reactions were dose-dependent and more frequent after receipt of mRNA-1010 than the active comparator. These interim data support continued development of mRNA-1010.

Outcomes after surgery in patients with and without recent influenza: a nationwide population-based study

Background

The influence of recent influenza infection on perioperative outcomes is not completely understood.

Method

Using Taiwan's National Health Insurance Research Data from 2008 to 2013, we conducted a surgical cohort study, which included 20,544 matched patients with a recent history of influenza and 10,272 matched patients without. The main outcomes were postoperative complications and mortality. We calculated odds ratios (ORs) and 95% confidence intervals (CIs) for the complications and for mortality in patients with a history of influenza within 1-14 days or 15-30 days compared with non-influenza controls.

Results

Compared with patients who had no influenza, patients with influenza within preoperative days 1-7 had increased risks of postoperative pneumonia (OR 2.22, 95% CI 1.81-2.73), septicemia (OR 1.98, 95% CI 1.70-2.31), acute renal failure (OR 2.10, 95% CI 1.47-3.00), and urinary tract infection (OR 1.45, 95% CI 1.23-1.70). An increased risk of intensive care admission, prolonged length of stay, and higher medical expenditure was noted in patients with history of influenza within 1-14 days.

Conclusion

We found that there was an association between influenza within 14 days preoperatively and the increased risk of postoperative complications, particularly with the occurrence of influenza within 7 days prior to surgery.

Sustained Increase in Very Low Influenza Vaccination Coverage in Residents and Healthcare Workers of Long-Term Care Facilities in Austria after Educational Interventions

Residents of long-term care facilities (LTCFs) are particularly at risk for influenza infections. We aimed to improve influenza vaccination coverage among residents and healthcare workers (HCWs) in four LTCFs by implementing educational programs and enhanced vaccination services. We compared vaccination coverage before and after the interventions (2017/18 and 2018/19 seasons). Data on vaccination adherence were recorded during a four-year observational period (2019/20 to 2022/23 seasons). Following the interventions, vaccination coverage increased significantly from 5.8% (22/377) to 19.1% (71/371) in residents and from 1.3% (3/234) to 19.7% (46/233) in HCWs (p < 0.001). During the observational period (2019/20 to 2022/23 seasons), vaccination coverage remained high in residents but decreased in HCWs. Vaccination adherence was significantly higher in residents and HCWs in LTCF 1 compared to the other three LTCFs. Our study suggests that a bundle of educational interventions and enhanced vaccination services can be an effective method for improving influenza vaccination coverage in LTCFs in both residents and HCWs. However, vaccination rates are still well below the recommended targets and further efforts are needed to increase vaccine coverage in our LTCFs.

Age Differences in Comorbidities, Presenting Symptoms, and Outcomes of Influenza Illness Requiring Hospitalization: A Worldwide Perspective From the Global Influenza Hospital Surveillance Network

Background

The Global Influenza Hospital Surveillance Network (GIHSN) was established in 2012 to conduct coordinated worldwide influenza surveillance. In this study, we describe underlying comorbidities, symptoms, and outcomes in patients hospitalized with influenza.

Methods

Between November 2018 and October 2019, GIHSN included 19 sites in 18 countries using a standardized surveillance protocol. Influenza infection was laboratory-confirmed with reverse-transcription polymerase chain reaction. A multivariate logistic regression model was utilized to analyze the extent to which various risk factors predict severe outcomes.

Results

Of 16 022 enrolled patients, 21.9% had laboratory-confirmed influenza; 49.2% of influenza cases were A/H1N1pdm09. Fever and cough were the most common symptoms, although they decreased with age (P < .001). Shortness of breath was uncommon among those <50 years but increased with age (P < .001). Middle and older age and history of underlying diabetes or chronic obstructive pulmonary disease were associated with increased odds of death and intensive care unit (ICU) admission, and male sex and influenza vaccination were associated with lower odds. The ICU admissions and mortality occurred across the age spectrum.

Conclusions

Both virus and host factors contributed to influenza burden. We identified age differences in comorbidities, presenting symptoms, and adverse clinical outcomes among those hospitalized with influenza and benefit from influenza vaccination in protecting against adverse clinical outcomes. The GIHSN provides an ongoing platform for global understanding of hospitalized influenza illness.

The Influenza-Induced Pulmonary Inflammatory Exudate in Susceptible Tpl2-Deficient Mice Is Dictated by Type I IFN Signaling

The most prominent host response to viral infection is the production of type 1 interferons (T1 IFNs). One host regulator of the T1 IFNs is the serine-threonine kinase, tumor progression locus 2 (TPL2). We have previously demonstrated that Tpl2^-/- mice succumb to infection with a low-pathogenicity influenza A strain (x31), in association with with increased pulmonary levels of interferon-β (IFN-β), chemokine CCL2, and excessive monocyte and neutrophil pulmonary infiltration. TPL2-dependent overexpression of IFN-β has been implicated in enhanced susceptibility to Mycobacterium tuberculosis; therefore, we examined the role of T1 IFNs in susceptibility of Tpl2^-/- mice to influenza. CCL2 overexpression and monocyte recruitment were normalized in Ifnar1^-/-Tpl2^-/- mice, confirming that TPL2 constrains inflammatory monocyte recruitment via inhibition of the T1 IFN/CCL2 axis. Unexpectedly, excessive neutrophil recruitment in Ifnar1^-/- strains was further exacerbated by simultaneous TPL2 genetic ablation in Ifnar1^-/-Tpl2^-/- by 7 dpi, accompanied by overexpression of neutrophil-regulating cytokines, CXCL1 and IFN-λ. Collectively, our data suggest that TPL2 and T1 IFNs synergize to inhibit neutrophil recruitment. However, treatment with the neutrophil-depleting anti-Ly6G antibody showed only a modest improvement in disease. Analysis of sorted innate immune populations revealed redundant expression of inflammatory mediators among neutrophils, inflammatory monocytes and alveolar macrophages. These findings suggest that targeting a single cell type or mediator may be inadequate to control severe disease characterized by a mixed inflammatory exudate. Future studies will consider TPL2-regulated pathways as potential predictors of severe influenza progression as well as investigate novel methods to modulate TPL2 function during viral infection.

Drivers of and barriers to routine adult vaccination: A systematic literature review

We performed a systematic literature review in PubMed and Embase (2016-2021) to investigate the drivers of and barriers to routine vaccination in adults aged 50 and older globally. A thematic assessment identified three categories across 61 publications: sociodemographic, health-related, and attitudinal. The most common sociodemographic determinants (factors identified in studies; n = 47) associated with vaccination uptake were economic status, age, education, and household composition, which had mixed effects on vaccine uptake. For health-related determinants (n = 27), individuals with comorbidities and health care consumption were the most common factors, both increased vaccine uptake. The most common attitudinal factors (n = 42) were self-efficacy, provider or other's recommendations, and vaccine-preventable disease awareness; across studies, all attitude factors had a positive effect, unlike the sociodemographic and health status categories. Findings suggest that patient and provider awareness and education campaigns are effective ways to increase uptake of routine vaccinations in older adults.

The Influence of COVID-19 Pandemic on Influenza Immunization in Saudi Arabia: Cross-Sectional Study

Introduction

Influenza vaccination is the primary control measure for severe complications caused by influenza viruses. Moreover, in the face of the COVID-19 pandemic, Saudi Arabia recommends vaccinating people at risk against influenza to minimise co-infection risk with SARS-CoV2. Therefore, this study aims to assess the Saudi population’s knowledge, attitude, and practice toward influenza vaccination during the COVID-19 pandemic. Moreover, we evaluate the impact of the COVID-19 pandemic on seasonal influenza vaccination.

Methods

This cross-sectional study was conducted using an online survey in Saudi Arabia between July to August 2021. Participants were invited to complete the questionnaire through a survey link sent to social media platforms.

Results

A total of 2410 participants were included in this study. Our data demonstrate a lack of practice, attitude, and knowledge, especially on the influenza virus’s symptoms, viral transmission, and vaccine efficacy. Moreover, this study showed that the COVID-19 pandemic significantly impacted seasonal influenza vaccination in the Saudi population by 1.5-times compared to the previous years.

Conclusion

COVID-19 pandemic has increased the hesitancy of Saudi participants in influenza vaccination due to the lack of knowledge. As the pandemic of COVID-19 is fading, awareness campaigns are needed to encourage the public about the importance of receiving the influenza vaccine, especially for those at high risk each year.

Association between social vulnerability and influenza and tetanus-diphtheria-acellular pertussis vaccination in pregnant and postpartum individuals

BACKGROUND

Despite current guidelines recommending universal vaccination, the frequency of vaccination in pregnancy for influenza and tetanus-diphtheria-acellular pertussis remains low.

OBJECTIVE

This study aimed to evaluate the association between community-level social vulnerability and influenza and anticipated tetanus-diphtheria-acellular pertussis vaccinations among pregnant and postpartum individuals.

STUDY DESIGN

We conducted a cross-sectional survey of vaccine hesitancy in the peripartum period among pregnant and postpartum participants enrolled in prenatal care at a single tertiary care center from March 22, 2021, to April 02, 2021. Participant addresses were geocoded using ArcGIS and linked at the census tract level. The primary exposure was community-level social vulnerability as measured by the US Centers for Disease Control and Prevention's Social Vulnerability Index. This index incorporates 15 census variables to produce a composite score and subscores across 4 major thematic domains (socioeconomic status, household composition and disability, minority status and language, and housing type and transportation). The scores range from 0 to 1, with higher values indicating greater social vulnerability. The primary outcomes were self-reported influenza vaccination during the current influenza season and having received or planning to receive the tetanus-diphtheria-acellular pertussis vaccination in pregnancy. We used multivariable logistic regression and adjusted for age, self-reported race and ethnicity, parity, trimester of pregnancy, and chronic comorbid conditions.

RESULTS

Of 456 assessed individuals (95% pregnant individuals and 5% postpartum individuals), the frequency of influenza vaccination was 58% (95% confidence interval, 53-62), and the anticipated tetanus-diphtheria-acellular pertussis vaccination was 72% (95% confidence interval, 68-76). Individuals from communities with a higher Social Vulnerability Index were less likely to report vaccination in pregnancy than those from communities with a lower Social Vulnerability Index. Specifically, for each 0.1-unit increase in the Social Vulnerability Index, the odds of influenza vaccination (adjusted odds ratio, 0.23; 95% confidence interval, 0.11-0.46) and anticipated tetanus-diphtheria-acellular pertussis vaccination (adjusted odds ratio, 0.24; 95% confidence interval, 0.11-0.53) decreased by >70%. By domain, the Social Vulnerability Index subscores of socioeconomic status (influenza adjusted odds ratio, 0.20 [95% confidence interval, 0.10-0.40]; tetanus-diphtheria-acellular pertussis adjusted odds ratio, 0.25 [95% confidence interval, 0.12-0.53]) and housing type and transportation (influenza adjusted odds ratio, 0.41 [95% confidence interval, 0.19-0.84; tetanus-diphtheria-acellular pertussis adjusted odds ratio, 0.39 [95% confidence interval, 0.18-0.87) were inversely associated with a lower odds of influenza and tetanus-diphtheria-acellular pertussis vaccinations.

CONCLUSION

Pregnant and postpartum individuals living in areas with higher social vulnerability were less likely to report influenza and anticipated tetanus-diphtheria-acellular pertussis vaccinations in pregnancy. The Social Vulnerability Index could be used as a tool to improve vaccine equity and address disparities in vaccination in pregnancy.

Rates of Severe Influenza-Associated Outcomes Among Older Adults Living With Diabetes-Influenza Hospitalization Surveillance Network (FluSurv-NET), 2012-2017

BACKGROUND

Diabetes mellitus (DM) is common among older adults hospitalized with influenza, yet data are limited on the impact of DM on risk of severe influenza-associated outcomes.

METHODS

We included adults aged ≥65 years hospitalized with influenza during 2012-2013 through 2016-2017 from the Influenza Hospitalization Surveillance Network (FluSurv-NET), a population-based surveillance system for laboratory-confirmed influenza-associated hospitalizations conducted in defined counties within 13 states. We calculated population denominators using the Centers for Medicare and Medicaid Services county-specific DM prevalence estimates and National Center for Health Statistics population data. We present pooled rates and rate ratios (RRs) of intensive care unit (ICU) admission, pneumonia diagnosis, mechanical ventilation, and in-hospital death for persons with and without DM. We estimated RRs and 95% confidence intervals (CIs) using meta-analysis with site as a random effect in order to control for site differences in the estimates.

RESULTS

Of 31 934 hospitalized adults included in the analysis, 34% had DM. Compared to those without DM, adults with DM had higher rates of influenza-associated hospitalization (RR, 1.57 [95% CI, 1.43-1.72]), ICU admission (RR, 1.84 [95% CI, 1.67-2.04]), pneumonia (RR, 1.57 [95% CI, 1.42-1.73]), mechanical ventilation (RR, 1.95 [95% CI, 1.74-2.20]), and in-hospital death (RR, 1.48 [95% CI, 1.23-1.80]).

CONCLUSIONS

Older adults with DM have higher rates of severe influenza-associated outcomes compared to those without DM. These findings reinforce the importance of preventing influenza virus infections through annual vaccination, and early treatment of influenza illness with antivirals in older adults with DM.

Predictors of influenza severity among hospitalized adults with laboratory confirmed influenza: Analysis of nine influenza seasons from the Valencia region, Spain

Purpose

Influenza hospitalizations contribute substantially to healthcare disruption. We explored the impact of ageing, comorbidities and other risk factors to better understand associations with severe clinical outcomes in adults hospitalized with influenza.

Methods

We analysed multi‐season data from adults ≥18 years, hospitalized with laboratory‐confirmed influenza in Valencia, Spain. Severity was defined as intensive care unit (ICU) admission, assisted ventilation and/or death. Generalized estimating equations were used to estimate associations between risk factors and severity. Rate of hospital discharge was analysed with a cumulative incidence function.

Results

Only 26% of influenza patients had their primary discharge diagnosis coded as influenza. Comorbidities were associated with severity among adults aged 50–79 years, with the highest odds ratio (OR) in patients with ≥3 comorbidities aged 50–64 years (OR = 6.7; 95% CI: 1.0–44.6). Morbid obesity and functional dependencies were also identified risk factors (ORs varying from 3 to 5 depending on age). The presence of increasing numbers of comorbidities was associated with prolonged hospital stay.

Conclusions

Influenza clinical outcomes are aggravated by the presence of comorbidities and ageing. Increased awareness of influenza among hospitalized patients could prompt clinical and public health interventions to reduce associated burden.

The feasibility of pragmatic influenza vaccine randomized controlled real-world trials in Denmark and England

We estimated the frequency of non-specific influenza-associated clinical endpoints to inform the feasibility of pragmatic randomized controlled trials (RCT) assessing relative vaccine effectiveness (rVE). Hospitalization rates of respiratory, cardiovascular and diabetic events were estimated from Denmark and England's electronic databases and stratified by age, comorbidity and influenza vaccination status. We included a seasonal average of 4.5 million Danish and 7.2 million English individuals, 17 and 32% with comorbidities. Annually, approximately 1% of Danish and 0.5% of English individuals were hospitalized for selected events, ~50% of them respiratory. Hospitalization rates were 40-50-fold and 2-10-fold higher in those >50 years and with comorbidities, respectively. Our findings suggest that a pragmatic RCT using non-specific endpoints is feasible. However, for outcomes with rates <2.5%, it would require randomization of ~100,000 participants to have the power to detect a rVE difference of ~13%. Targeting selected groups (older adults, those with comorbidities) where frequency of events is high would improve trial efficiency.

Effect of influenza vaccination on the outcomes of hospitalization for kidney disease in a geriatric population: A propensity-score matched study

Background and aims

The effects of influenza vaccination (IV) on the outcomes of patients with kidney disease (KD) are not completely understood. We aimed to evaluate and compare the outcomes during admission of KD between elderly patients who did or did not receive an IV within the previous 12 months.

Methods

We used health insurance research data in Taiwan and conducted a population-based cohort study that included 22,590 older people aged ≥ 65 years who were hospitalized for KD in 2008–2013. We performed propensity score matching (case-control ratio 1:1) to select 4386 eligible IV recipients and 4386 nonrecipient controls for comparison. The adjusted odds ratios (ORs) with 95% confidence intervals (CIs) of IV associated with complications and mortality during KD admission were calculated using multivariable logistic regression analyses.

Results

During hospitalization for KD, IV was significantly associated with lower risks of 30-day in-hospital mortality (OR 0.56, 95% CI 0.39–0.82), septicemia (OR 0.77, 95% CI 0.68–0.87), and intensive care (OR 0.85, 95% CI 0.75–0.96). Additionally, IV recipients had a shorter length of hospital stay and lower medical expenditure than nonrecipients. Subgroup analyses further showed that the association of IV with reduced adverse events was confined to patients aged ≥ 75 years.

Conclusions

Previous IV was associated with reduced risks of complications and mortality and in elderly patients hospitalized for KD. We raised the possibility and suggested the need to promote IV for this susceptible population of patients with KD.

Relative Effectiveness of Cell-Cultured versus Egg-Based Seasonal Influenza Vaccines in Preventing Influenza-Related Outcomes in Subjects 18 Years Old or Older: A Systematic Review and Meta-Analysis

Avian mutations in vaccine strains obtained from embryonated eggs could impair vaccine effectiveness. We performed a systematic review and meta-analysis of the adjusted relative vaccine effectiveness (arVE) of seed cell-cultured influenza vaccines (ccIV) compared to egg-based influenza vaccines (eIV) in preventing laboratory-confirmed influenza related outcomes (IRO) or IRO by clinical codes, in subjects 18 and over. We completed the literature search in January 2021; applied exclusion criteria, evaluated risk of bias of the evidence, and performed heterogeneity, publication bias, qualitative, quantitative and sensitivity analyses. All estimates were computed using a random approach. International Prospective Register of Systematic Reviews, CRD42021228290. We identified 12 publications that reported 26 adjusted arVE results. Five publications reported 13 laboratory confirmed arVE and seven reported 13 code-ascertained arVE. Nine publications with 22 results were at low risk of bias. Heterogeneity was explained by season. We found a significant 11% (8 to 14%) adjusted arVE favoring ccIV in preventing any IRO in the 2017–2018 influenza season. The arVE was 3% (−2% to 7%) in the 2018–2019 influenza season. We found moderate evidence of a significant advantage of the ccIV in preventing IRO, compared to eIV, in a well-matched A(H3N2) predominant season.

Association between Maoto Use and Hospitalization for Seasonal Influenza in a Nonelderly Cohort in Japan

Objective Maoto is a traditional Japanese Kampo formula used to treat influenza. However, clinical evidence for maoto has been limited to small-scale studies of its effect in alleviating symptoms. The present study evaluated whether or not the addition of maoto to a neuraminidase inhibitor was associated with a reduction in hospitalization following influenza. Methods Using the JMDC Claims Database, we identified outpatients <60 years old who were diagnosed with influenza by an antigen test from September 2013 to August 2018. One-to-five propensity score matching was conducted between patients who received maoto in addition to a neuraminidase inhibitor and those who received a neuraminidase inhibitor alone. Hospitalization within seven days of the influenza diagnosis was compared in the matched groups using the Mantel-Haenszel test. Results We identified 1.79 million cases of influenza from the database in the 5-year study period. Maoto was prescribed for 3.9% of the 1.67 million cases receiving a neuraminidase inhibitor. In the 64,613 propensity score-matched groups of patients, the 7-day hospitalization rate was 0.116% (n=75) for patients with maoto and 0.122% (n=394) for patients without maoto. The difference between these treatment groups was nonsignificant (common odds ratio, 0.95; 95% confidence interval, 0.74 to 1.22; p=0.695). Conclusion The addition of maoto to a neuraminidase inhibitor was not associated with a decrease in hospitalization among nonelderly patients with influenza. Further research is necessary to clarify the indication and efficacy of maoto.

Moving the Needle on Atherosclerotic Cardiovascular Disease and Heart Failure with Influenza Vaccination

PURPOSE OF REVIEW

The interplay between viral respiratory infections and cardiovascular disease has been most comprehensively researched using seasonal and pandemic influenza viruses as case studies. Here, we summarize the latest international observational research and clinical trials that examined the association between influenza, influenza vaccines, and cardiovascular disease, while contextualizing their findings within those of landmark studies.

RECENT FINDINGS

Most recent observational literature found that one in eight adults hospitalized with laboratory-confirmed influenza infection experienced an acute cardiovascular event. The latest meta-analysis of the cardioprotective effects of influenza vaccine found a 25% reduced risk of all-cause death. There are four large cardiovascular outcome trials assessing the cardioprotective effects of different influenza vaccine strategies. Among these, the INVESTED study showed there is no significant difference between the high-dose trivalent and standard-dose quadrivalent influenza vaccines in reducing all-cause mortality or cardiopulmonary hospitalizations in a high-risk patient group with pre-existing cardiovascular disease. Persons with cardiovascular disease represent a high priority group for viral vaccines; hence, using robust evidence to increase vaccine confidence among patients and practitioners is integral as we prepare for a possible influenza resurgence in the coming years.

Increased Risks of Death and Hospitalization in Influenza/Pneumonia and Sepsis for Individuals Affected by Psychotic Disorders, Bipolar Disorders, and Single Manic Episodes: A Retrospective Cross-Sectional Study

Individuals with severe mental disorders (SMDs) such as psychotic disorders, bipolar disorders, and single manic episodes have increased mortality associated with COVID-19 infection. We set up a population-based study to examine whether individuals with SMD also had a higher risk of hospitalization and death from other infectious conditions. Anonymized and summarized data from multiple Swedish patient registers covering the entire Swedish population were supplied by the Swedish National Board of Health and Welfare. The frequencies of hospitalizations and deaths associated with influenza/pneumonia and sepsis in individuals with SMD were compared with the rest of the population during 2018–2019. Possible contributing comorbidities were also examined, of which diabetes, cardiovascular disease, chronic lung disease, and hypertension were chosen. A total of 7,780,727 individuals were included in the study; 97,034 (1.2%) cases with SMD and 7,683,693 (98.8%) controls. Individuals with SMD had increased risk of death associated with influenza/pneumonia (OR = 2.06, 95% CI [1.87–2.27]) and sepsis (OR = 1.61, 95% CI [1.38–1.89]). They also had an increased risk of hospitalization associated with influenza/pneumonia (OR = 2.12, 95% CI [2.03–2.20]) and sepsis (OR = 1.89, 95% CI [1.75–2.03]). Our results identify a need for further evaluation of whether these individuals should be included in prioritized risk groups for vaccination against infectious diseases other than COVID-19.

Competing Bioaerosols May Influence the Seasonality of Influenza-Like Illnesses, including COVID-19. The Chicago Experience

Data from Chicago confirm the end of flu season coincides with the beginning of pollen season. More importantly, the end of flu season also coincides with onset of seasonal aerosolization of mold spores. Overall, the data suggest bioaerosols, especially mold spores, compete with viruses for a shared receptor, with the periodicity of influenza-like illnesses, including COVID-19, a consequence of seasonal factors that influence aerosolization of competing species.

Influenza Vaccine Effectiveness in Inpatient and Outpatient Settings in the United States, 2015-2018

BACKGROUND

Demonstration of influenza vaccine effectiveness (VE) against hospitalized illness in addition to milder outpatient illness may strengthen vaccination messaging. Our objective was to compare patient characteristics and VE between United States (US) inpatient and outpatient VE networks.

METHODS

We tested adults with acute respiratory illness (ARI) for influenza within 1 outpatient-based and 1 hospital-based VE network from 2015 through 2018. We compared age, sex, and high-risk conditions. The test-negative design was used to compare vaccination odds in influenza-positive cases vs influenza-negative controls. We estimated VE using logistic regression adjusting for site, age, sex, race/ethnicity, peak influenza activity, time to testing from, season (overall VE), and underlying conditions. VE differences (ΔVE) were assessed with 95% confidence intervals (CIs) determined through bootstrapping with significance defined as excluding the null.

RESULTS

The networks enrolled 14 573 (4144 influenza-positive) outpatients and 6769 (1452 influenza-positive) inpatients. Inpatients were older (median, 62 years vs 49 years) and had more high-risk conditions (median, 4 vs 1). Overall VE across seasons was 31% (95% CI, 26%-37%) among outpatients and 36% (95% CI, 27%-44%) among inpatients. Strain-specific VE (95% CI) among outpatients vs inpatients was 37% (25%-47%) vs 53% (37%-64%) against H1N1pdm09; 19% (9%-27%) vs 23% (8%-35%) against H3N2; and 46% (38%-53%) vs 46% (31%-58%) against B viruses. ΔVE was not significant for any comparison across all sites.

CONCLUSIONS

Inpatients and outpatients with ARI represent distinct populations. Despite comparatively poor health among inpatients, influenza vaccination was effective in preventing influenza-associated hospitalizations.

Respiratory Syncytial Virus-Associated Hospitalizations Among Adults With Chronic Medical Conditions

BACKGROUND

In contrast with respiratory disease caused by influenza, information on the risk of respiratory syncytial virus (RSV) disease among adults with chronic medical conditions (CMCs) is limited.

METHODS

We linked population-based surveillance of acute respiratory illness hospitalizations to national administrative data to estimate seasonal RSV hospitalization rates among adults aged 18-80 years with the following preexisting CMCs: chronic obstructive pulmonary disease (COPD), asthma, congestive heart failure (CHF), coronary artery disease (CAD), cerebrovascular accidents (CVA), diabetes mellitus (DM), and end-stage renal disease (ESRD). Age- and ethnicity-adjusted rates stratified by age group were estimated.

RESULTS

Among 883 999 adult residents aged 18-80 years, 281 RSV-positive hospitalizations were detected during 2012-2015 winter seasons. Across all ages, RSV hospitalization rates were significantly higher among adults with COPD, asthma, CHF, and CAD compared with those without each corresponding condition. RSV hospitalization rates were significantly higher among adults with ESRD aged 50-64 years and adults with DM aged 18-49 years and 65-80 years compared with adults in each age group without these conditions. No increased risk was seen for adults with CVA. The CMC with the highest risk of RSV hospitalization was CHF (incidence rate ratio [IRR] range, 4.6-36.5 across age strata) and COPD (IRR range, 9.6-9.7). Among RSV-positive adults, CHF and COPD were independently associated with increased length of hospital stay.

CONCLUSIONS

Adults with specific CMCs are at increased risk of RSV hospitalizations. Age affects this relationship for some CMCs. Such populations maybe relevant for future RSV prevention strategies.

Behavior of hospitalized severe influenza cases according to the outcome variable in Catalonia, Spain, during the 2017-2018 season

Influenza is an important cause of severe illness and death among patients with underlying medical conditions and in the elderly. The aim of this study was to investigate factors associated with ICU admission and death in patients hospitalized with severe laboratory-confirmed influenza during the 2017–2018 season in Catalonia. An observational epidemiological case-to-case study was carried out. Reported cases of severe laboratory-confirmed influenza requiring hospitalization in 2017–2018 influenza season were included. Mixed-effects regression analysis was used to estimate the factors associated with ICU admission and death. A total of 1306 cases of hospitalized severe influenza cases were included, of whom 175 (13.4%) died and 217 (16.6%) were ICU admitted. Age 65–74 years and ≥ 75 years and having ≥ 2 comorbidities were positively associated with death (aOR 3.19; 95%CI 1.19–8.50, aOR 6.95, 95%CI 2.76–1.80 and aOR 1.99; 95%CI 1.12–3.52, respectively). Neuraminidase inhibitor treatment and pneumonia were negatively associated with death. The 65–74 years and ≥ 75 years age groups were negatively associated with ICU admission (aOR 0.41; 95%CI 0.23–0.74 and aOR 0.30; 95%CI 0.17–0.53, respectively). A factor positively associated with ICU admission was neuraminidase inhibitor treatment. Our results support the need to investigate the worst outcomes of hospitalized severe cases, distinguishing between death and ICU admission.

Current Activities Centered on Healthy Living and Recommendations for the Future: A Position Statement from the HL-PIVOT Network

We continue to increase our cognizance and recognition of the importance of healthy living (HL) behaviors and HL medicine (HLM) to prevent and treat chronic disease. The continually unfolding events precipitated by the coronavirus disease 2019 (COVID-19) pandemic have further highlighted the importance of HL behaviors, as indicated by the characteristics of those who have been hospitalized and died from this viral infection. There has already been recognition that leading a healthy lifestyle, prior to the COVID-19 pandemic, may have a substantial protective effect in those who become infected with the virus. Now more than ever, HL behaviors and HLM are essential and must be promoted with a renewed vigor across the globe. In response to the rapidly evolving world since the beginning of the COVID-19 pandemic, and the clear need to change lifestyle behaviors to promote human resilience and quality of life, the HL for Pandemic Event Protection (HL-PIVOT) network was established. The 4 major areas of focus for the network are: (1) knowledge discovery and dissemination; (2) education; (3) policy; (4) implementation. This HL-PIVOT network position statement provides a current synopsis of the major focus areas of the network, including leading research in the field of HL behaviors and HLM, examples of best practices in education, policy, and implementation, and recommendations for the future.

Barriers Associated with the Uptake Ratio of Seasonal Flu Vaccine and Ways to Improve Influenza Vaccination Coverage among Young Health Care Workers in Poland

Despite not being full-time health care workers, annual flu vaccination is nevertheless an important consideration for medical students. This study examined the reasons for refusing flu vaccination among medical students, a group characterized by low vaccination coverage, despite the fact that the flu vaccine is arguably the most effective way of preventing serious flu complications. A cross-sectional survey was performed of 1313 students at the Medical University of Lodz. The findings indicate that the main sites of vaccination were primary care centers, and main source of information about influenza vaccination (about 90% of cases) was the general practitioner (GP). The most common motivations for vaccination were a recommendation by the family doctor or the belief that it was an important factor for protection against influenza. Most students reported various adverse effects after vaccination, usually mild pain at the site of vaccination, malaise, or fever. The main reasons for rejecting influenza vaccination were the apparent low risk of disease, the need for annual vaccination, the need to pay for it, lack of time or opportunity, lack of vaccination promotion, negative attitudes toward the flu vaccine, or the belief that there are other methods of preventing flu. To increase long-term vaccine acceptance and increase the vaccination rate among medical students and qualified health care workers, there is a need to adapt the health system and to initiate ongoing promotion programs at university to raise consciousness, promote vaccinations, and develop clinical skills for immunization.

Clinical features and outcomes of COVID-19 in older adults: a systematic review and meta-analysis

Background

Few studies have focused on exploring the clinical characteristics and outcomes of COVID-19 in older patients. We conducted this systematic review and meta-analysis to have a better understanding of the clinical characteristics of older COVID-19 patients.

Methods

A systematic search of PubMed and Scopus was performed from December 2019 to May 3rd, 2020. Observational studies including older adults (age ≥ 60 years) with COVID-19 infection and reporting clinical characteristics or outcome were included. Primary outcome was assessing weighted pooled prevalence (WPP) of severity and outcomes. Secondary outcomes were clinical features including comorbidities and need of respiratory support.

Result

Forty-six studies with 13,624 older patients were included. Severe infection was seen in 51% (95% CI– 36-65%, I²–95%) patients while 22% (95% CI– 16-28%, I²–88%) were critically ill. Overall, 11% (95% CI– 5-21%, I²–98%) patients died. The common comorbidities were hypertension (48, 95% CI– 36-60% I²–92%), diabetes mellitus (22, 95% CI– 13-32%, I²–86%) and cardiovascular disease (19, 95% CI – 11-28%, I²–85%). Common symptoms were fever (83, 95% CI– 66-97%, I²–91%), cough (60, 95% CI– 50-70%, I²–71%) and dyspnoea (42, 95% CI– 19-67%, I²–94%). Overall, 84% (95% CI– 60-100%, I²–81%) required oxygen support and 21% (95% CI– 0-49%, I²–91%) required mechanical ventilation. Majority of studies had medium to high risk of bias and overall quality of evidence was low for all outcomes.

Conclusion

Approximately half of older patients with COVID-19 have severe infection, one in five are critically ill and one in ten die. More high-quality evidence is needed to study outcomes in this vulnerable patient population and factors affecting these outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02261-3.

Comparison of clinical characteristics and disease outcome of COVID-19 and seasonal influenza

While several studies have described the clinical course of patients with coronavirus disease 2019 (COVID-19), direct comparisons with patients with seasonal influenza are scarce. We compared 166 patients with COVID-19 diagnosed between February 27 and June 14, 2020, and 255 patients with seasonal influenza diagnosed during the 2017-18 season at the same hospital to describe common features and differences in clinical characteristics and course of disease. Patients with COVID-19 were younger (median age [IQR], 59 [45-71] vs 66 [52-77]; P < 0001) and had fewer comorbidities at baseline with a lower mean overall age-adjusted Charlson Comorbidity Index (mean [SD], 3.0 [2.6] vs 4.0 [2.7]; P < 0.001) than patients with seasonal influenza. COVID-19 patients had a longer duration of hospitalization (mean [SD], 25.9 days [26.6 days] vs 17.2 days [21.0 days]; P = 0.002), a more frequent need for oxygen therapy (101 [60.8%] vs 103 [40.4%]; P < 0.001) and invasive ventilation (52 [31.3%] vs 32 [12.5%]; P < 0.001) and were more frequently admitted to the intensive care unit (70 [42.2%] vs 51 [20.0%]; P < 0.001) than seasonal influenza patients. Among immunocompromised patients, those in the COVID-19 group had a higher hospital mortality compared to those in the seasonal influenza group (13 [33.3%] vs 8 [11.6%], P = 0.01). In conclusion, we show that COVID-19 patients were younger and had fewer baseline comorbidities than seasonal influenza patients but were at increased risk for severe illness. The high mortality observed in immunocompromised COVID-19 patients emphasizes the importance of protecting these patient groups from SARS-CoV-2 infection.

Comparison of clinical characteristics and disease outcome of COVID-19 and seasonal influenza

While several studies have described the clinical course of patients with coronavirus disease 2019 (COVID-19), direct comparisons with patients with seasonal influenza are scarce. We compared 166 patients with COVID-19 diagnosed between February 27 and June 14, 2020, and 255 patients with seasonal influenza diagnosed during the 2017-18 season at the same hospital to describe common features and differences in clinical characteristics and course of disease. Patients with COVID-19 were younger (median age [IQR], 59 [45-71] vs 66 [52-77]; P < 0001) and had fewer comorbidities at baseline with a lower mean overall age-adjusted Charlson Comorbidity Index (mean [SD], 3.0 [2.6] vs 4.0 [2.7]; P < 0.001) than patients with seasonal influenza. COVID-19 patients had a longer duration of hospitalization (mean [SD], 25.9 days [26.6 days] vs 17.2 days [21.0 days]; P = 0.002), a more frequent need for oxygen therapy (101 [60.8%] vs 103 [40.4%]; P < 0.001) and invasive ventilation (52 [31.3%] vs 32 [12.5%]; P < 0.001) and were more frequently admitted to the intensive care unit (70 [42.2%] vs 51 [20.0%]; P < 0.001) than seasonal influenza patients. Among immunocompromised patients, those in the COVID-19 group had a higher hospital mortality compared to those in the seasonal influenza group (13 [33.3%] vs 8 [11.6%], P = 0.01). In conclusion, we show that COVID-19 patients were younger and had fewer baseline comorbidities than seasonal influenza patients but were at increased risk for severe illness. The high mortality observed in immunocompromised COVID-19 patients emphasizes the importance of protecting these patient groups from SARS-CoV-2 infection.

Comparing intravenous peramivir with oral oseltamivir for patients with influenza: a meta-analysis of randomized controlled trials

BACKGROUND

The study was to compare the efficacy between IV peramivir and oral oseltamivir treatments in patients with influenza.

METHODS

The PubMed, EMBASE, Scopus, ClinicalTrials.gov, and Cochrane Library databases were searched for studies published before January 2020.

RESULTS

The meta-analysis was conducted to calculate the pooled effect size by using a random-effects model. Seven randomized controlled trials (RCTs) including 1,138 patients were reviewed. The incidence of total complications revealed no significant difference between 600 mg IV peramivir (P600) and 75 mg oral oseltamivir (O75) treatments (2.8% vs. 4.1%; risk ratio [RR] = 0.70; 95% confidence interval [CI]: 0.36-1.38). The incidence of pneumonia was not significantly different between the P600 and O75 treatment groups (2.2% vs. 2.7%; RR = 0.74; 95% CI: 0.37-1.51). Regarding the time to the alleviation of symptoms, no difference was found in P600 and O75 treatment (MD = -3.00; 95% CI: -11.07 to 5.06). The rate of fever clearance in 24 h and the time to fever resolution were not statistically different between the IV peramivir and oral oseltamivir treatments (at different dosages) groups.

CONCLUSIONS

The treatment of influenza with IV peramivir or oral oseltamivir had similar clinical efficacy.

Diagnosing Chronic Obstructive Airway Disease on a Smartphone Using Patient-Reported Symptoms and Cough Analysis: Diagnostic Accuracy Study

Background

Rapid and accurate diagnosis of chronic obstructive pulmonary disease (COPD) is problematic in acute care settings, particularly in the presence of infective comorbidities.

Objective

The aim of this study was to develop a rapid smartphone-based algorithm for the detection of COPD in the presence or absence of acute respiratory infection and evaluate diagnostic accuracy on an independent validation set.

Methods

Participants aged 40 to 75 years with or without symptoms of respiratory disease who had no chronic respiratory condition apart from COPD, chronic bronchitis, or emphysema were recruited into the study. The algorithm analyzed 5 cough sounds and 4 patient-reported clinical symptoms, providing a diagnosis in less than 1 minute. Clinical diagnoses were determined by a specialist physician using all available case notes, including spirometry where available.

Results

The algorithm demonstrated high positive percent agreement (PPA) and negative percent agreement (NPA) with clinical diagnosis for COPD in the total cohort (N=252; PPA=93.8%, NPA=77.0%, area under the curve [AUC]=0.95), in participants with pneumonia or infective exacerbations of COPD (n=117; PPA=86.7%, NPA=80.5%, AUC=0.93), and in participants without an infective comorbidity (n=135; PPA=100.0%, NPA=74.0%, AUC=0.97). In those who had their COPD confirmed by spirometry (n=229), PPA was 100.0% and NPA was 77.0%, with an AUC of 0.97.

Conclusions

The algorithm demonstrated high agreement with clinical diagnosis and rapidly detected COPD in participants presenting with or without other infective lung illnesses. The algorithm can be installed on a smartphone to provide bedside diagnosis of COPD in acute care settings, inform treatment regimens, and identify those at increased risk of mortality due to seasonal or other respiratory ailments.

Trial Registration

Australian New Zealand Clinical Trials Registry ACTRN12618001521213; http://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=375939

A Comparison of the Attitudes to Influenza Vaccination Held by Nursing, Midwifery, Pharmacy, and Public Health Students and Their Knowledge of Viral Infections

Influenza is a viral vaccine-preventable disease. The present study aims to explore the attitude to influenza immunization and the knowledge of influenza among students in Poland. A cross-sectional survey was conducted at the end of 2019 and the beginning of 2020 among students of Nursing, Midwifery, Pharmacy, and Public health in all years of study. Data was obtained from 1137 students (90.7% female, 9.3% male), mean age 21.3 ± 1.62 years. The urban students were more likely to be vaccinated against seasonal influenza than rural students (OR: 1.52; 95% CI [1.10-2.10], p = 0.010362). The students of Public health were more likely to be vaccinated against influenza (48.9%, regularly annually 1.1%) than Pharmacy (31%, regularly annually 2.5%), Nursing (30.7%, regularly annually 1.3%) or Midwifery (25.1%, regularly annually 2.4%). First-year and second-year students were vaccinated more often (OR: 2.75; 95% CI [1.99-3.82], p = 0.00000; OR: 1.84; 95% CI [1.32-2.59], p = 0.0004, respectively) than later-year students. All students reported the main reasons for vaccination to be their own protection and parental decision. Concluded, present findings demonstrate a low prevalence of flu vaccination among medical students. Therefore, strategies are needed to increase the uptake of influenza vaccine in students, especially considering the future contact between this group of future health care workers and higher risk groups.

The immune response to influenza in older humans: beyond immune senescence

Despite widespread influenza vaccination programs, influenza remains a major cause of morbidity and mortality in older adults. Age-related changes in multiple aspects of the adaptive immune response to influenza have been well-documented including a decline in antibody responses to influenza vaccination and changes in the cell-mediated response associated with immune senescence. This review will focus on T cell responses to influenza and influenza vaccination in older adults, and how increasing frailty or coexistence of multiple (≥2) chronic conditions contributes to the loss of vaccine effectiveness for the prevention of hospitalization. Further, dysregulation of the production of pro- and anti-inflammatory mediators contributes to a decline in the generation of an effective CD8 T cell response needed to clear influenza virus from the lungs. Current influenza vaccines provide only a weak stimulus to this arm of the adaptive immune response and rely on re-stimulation of CD8 T cell memory related to prior exposure to influenza virus. Efforts to improve vaccine effectiveness in older adults will be fruitless until CD8 responses take center stage.