Hospitalization For Acute Respiratory Infections Research Articles

Epidemiological characteristics and meteorological factors of acute respiratory infections (ARIs) in hospitalized children in eastern Guangdong, China

Acute respiratory infections (ARIs) are the most common issue in pediatric clinical practice. They pose a significant public threat, with high morbidity and mortality rates worldwide. Aiming at understanding the epidemiological characteristics of respiratory pathogens and their risk factors among children in eastern Guangdong, China. Samples obtained from 15,993 children hospitalized with ARIs in eastern Guangdong Province were tested for 14 pathogens via multiplex polymerase chain reaction (PCR) from May 2019 to July 2023. The number of hospitalizations for ARIs was correlated with pathogens, age, meteorological parameters, and the pandemic of COVID-19. The data were analyzed by different statistical methods. Among all the samples, the positive rate with ARIs accounted for 68.94% (11,026/15,993) in hospitalized patients. Cytomegalovirus (CMV) (24.49%), Streptococcus pneumoniae (SP) (20.54%), and Respiratory Syncytial Virus (RSV) (14.16%) were the top three pathogens with the greatest infection rates. Among hospitalized patients, there were more single infections in pediatric patients (40.91%, P < 0.001). Compared with bacterial infection and mixed infection, the detection rate of virus infection was higher in pediatric (36.04%, P < 0.001). Age-related increases in Mycoplasma pneumoniae (MP) infection (r = 0.729, P < 0.001) and decreases in RSV infection were observed (r = 0.88, P < 0.001). The virus infection peaked at six months, and the bacterial infection and mixed infection peaked at 1–3 years. Viral pathogens are on the rise in the post-pandemic era. The prevalence of SP infection was more influenced by the Air Quality Index (AQI), RSV infections were more clearly influenced by temperature, and Influenza A virus (IAV) infections were more strongly correlated with both the AQI and relative humidity (P < 0.001). This study highlights the need of keeping an eye on monitoring meteorological factors in assessing hospitalizations for pediatric ARIs in eastern Guangdong, China, especially RSV- and SP-associated hospitalizations.

Inconsistent Increase in Age at Respiratory Syncytial Virus Hospitalization of Children Aged

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic disrupted respiratory syncytial virus (RSV) seasonality. To optimize the use and evaluation of RSV infant immunization strategies, monitoring changes in RSV epidemiology is essential. Hospitalizations for acute respiratory infections (ARIs) and RSV-coded ARI in children <2 years were extracted in 4 European hospitals, according to predefined case definitions (International Classification of Diseases, Tenth Revision codes). Prepandemic RSV seasons (2017-2018 to 2019-2020) were compared to 2021-2022 and 2022-2023. In 2021-2022 and 2022-2023, the peak number of RSV hospitalizations was higher than prepandemic peaks after short periods of RSV circulation, and lower than prepandemic peaks after long periods of RSV circulation. A greater proportion of RSV hospitalizations occurred in children 1 to <2 years in 2021-2022 in the Netherlands (18% vs 9%, P = .04). No increase in age was observed elsewhere. High-risk children represented a greater proportion of RSV hospitalizations during the pandemic. The proportion of pediatric intensive care unit admissions did not increase. A decrease in population immunity has been linked to older age at RSV hospitalization. We did not observe an increase in age in 3 of the 4 participating countries. Broad age categories may have prevented detecting an age shift. Monitoring RSV epidemiology is essential as Europe implements RSV immunization.

Impact of SARS-CoV-2 Pandemic on Emergency Hospitalizations for Acute Respiratory Infections: The Experience of a Paediatric Tertiary Care Hospital in Italy.

Acute respiratory infections (ARIs) are a major healthcare issue in children. The SARS-CoV-2 pandemic changed the epidemiology of ARIs; the aims of this study are to characterize the epidemiological trend of ARI emergency hospitalizations and virology results and to estimate the association of ARI emergency hospitalizations with respiratory viruses from January 2018 to June 2023. This study was carried out in an Italian tertiary care children's hospital (Bambino Gesù Children's Hospital). The demographic and clinical information of children who accessed the Emergency Department (ED) with ARI and were hospitalized were retrospectively extracted from the electronic health records. Multivariate linear regression model was used to compare the number of ARI hospital admissions with the reported temporal trends in viruses diagnosed from respiratory samples throughout the same time period. During the study period, there were 92,140 ED visits and 10,541 hospitalizations due to ARIs, reflecting an admission rate of 11.4%. The highest proportion of hospitalizations occurred in infants ≤ 1 year of age (n = 4840, 45.9% of total admissions), with a hospitalization rate of 22.6%. Emergency hospitalizations aligned closely with the predictions made by the multivariate regression model; peaks in hospitalizations reflected Respiratory Syncytial Virus (RSV) circulation. ARI hospital urgent admissions are a relevant component of ARI disease burden in children. RSV prevention and control are crucial to limit the risk of urgent hospitalizations due to ARIs.

The Changing Landscape of Respiratory Viruses Contributing to Hospitalizations in Quebec, Canada: Results From an Active Hospital-Based Surveillance Study.

A comprehensive description of the combined effect of SARS-CoV-2 and respiratory viruses other than SARS-CoV-2 (ORVs) on acute respiratory infection (ARI) hospitalizations is lacking. This study aimed to compare the viral etiology of ARI hospitalizations before the pandemic (8 prepandemic influenza seasons, 2012-13 to 2019-20) and during 3 pandemic years (periods of increased SARS-CoV-2 and ORV circulation in 2020-21, 2021-22, and 2022-23) from an active hospital-based surveillance network in Quebec, Canada. We compared the detection of ORVs and SARS-CoV-2 during 3 pandemic years to that in 8 prepandemic influenza seasons among patients hospitalized with ARI who were tested systematically by the same multiplex polymerase chain reaction (PCR) assay during periods of intense respiratory virus (RV) circulation. The proportions of infections between prepandemic and pandemic years were compared by using appropriate statistical tests. During prepandemic influenza seasons, overall RV detection was 92.7% (1384/1493) (respiratory syncytial virus [RSV]: 721/1493, 48.3%; coinfections: 456/1493, 30.5%) in children (<18 years) and 62.8% (2723/4339) (influenza: 1742/4339, 40.1%; coinfections: 264/4339, 6.1%) in adults. Overall RV detection in children was lower during pandemic years but increased from 58.6% (17/29) in 2020-21 (all ORVs; coinfections: 7/29, 24.1%) to 90.3% (308/341) in 2021-22 (ORVs: 278/341, 82%; SARS-CoV-2: 30/341, 8.8%; coinfections: 110/341, 32.3%) and 88.9% (361/406) in 2022-23 (ORVs: 339/406, 84%; SARS-CoV-2: 22/406, 5.4%; coinfections: 128/406, 31.5%). In adults, overall RV detection was also lower during pandemic years but increased from 43.7% (333/762) in 2020-21 (ORVs: 26/762, 3.4%; SARS-CoV-2: 307/762, 40.3%; coinfections: 7/762, 0.9%) to 57.8% (731/1265) in 2021-22 (ORVs: 179/1265, 14.2%; SARS-CoV-2: 552/1265, 43.6%; coinfections: 42/1265, 3.3%) and 50.1% (746/1488) in 2022-23 (ORVs: 409/1488, 27.5%; SARS-CoV-2: 337/1488, 22.6%; coinfections: 36/1488, 2.4%). No influenza or RSV was detected in 2020-21; however, their detection increased in the 2 subsequent years but did not reach prepandemic levels. Compared to the prepandemic period, the peaks of RSV hospitalization shifted in 2021-22 (16 weeks earlier) and 2022-23 (15 weeks earlier). Moreover, the peaks of influenza hospitalization shifted in 2021-22 (17 weeks later) and 2022-23 (4 weeks earlier). Age distribution was different compared to the prepandemic period, especially during the first pandemic year. Significant shifts in viral etiology, seasonality, and age distribution of ARI hospitalizations occurred during the 3 pandemic years. Changes in age distribution observed in our study may reflect modifications in the landscape of circulating RVs and their contribution to ARI hospitalizations. During the pandemic period, SARS-CoV-2 had a low contribution to pediatric ARI hospitalizations, while it was the main contributor to adult ARI hospitalizations during the first 2 seasons and dropped below ORVs during the third pandemic season. Evolving RVs epidemiology underscores the need for increased scrutiny of ARI hospitalization etiology to inform tailored public health recommendations.

Respiratory syncytial virus-associated hospitalizations among children: an Italian retrospective observational study

BackgroundRespiratory syncytial virus (RSV), a single-stranded RNA virus, is a leading cause of hospitalization in infants, especially ≤ 2 months of life. In the light new immunization strategies adoption, we described epidemiological and clinical characteristics of RSV-associated hospitalizations in pediatric and neonatal intensive care units of the Policlinico Foggia Hospital, Apulia Region, Italy.MethodsHospitalized children with a laboratory-confirmed RSV infection from 2011 to 2023 were retrospectively evaluated. Clinical information was collected from Hospital Discharge Registry in the period 2011–2020. The proportion of the hospitalization for acute respiratory infections (ARIs) associated to RSV was calculated and the hospitalization cost was analyzed by using the diagnosis-related group reimbursement rate. The anticipated impact of immunization either with monoclonal antibodies or maternal immunization on the number of hospitalizations was estimated. All analyses and quality assessment were performed using STATA/SE15.0.ResultsA total of 1,005 RSV-cases were included in the study, of which 86.3% occurred between December-March. In the period 2011–2020, 832 RSV-cases were matched with the corresponding hospital admissions; 75.2% were aged < 1 year (49.6% 0–2 months). Bronchiolitis was the most frequent admission diagnosis occurring in 63.3% of patients; 25% of children were affected by a very severe RSV-disease. Younger age ≤ 2 months (OR:14.8, 95%CI:8.30–26.31, p = 0.000), higher length-of-hospital-stay (OR:1.01, 95%CI:1.0–1.02, p = 0.030) and history of prematurity (OR:4.4, 95%CI:1.57–12.11, p = 0.005) were associated with a higher disease severity. RSV caused 48.9% of ARIs among children < 1 year. The mean cost of an RSV-associated hospitalization was 3,036 euros/year, with the higher cost in the 0–2 months age group (4,225 euros/year). Immunization programs with nirsevimab could prevent 51.4 RSV hospitalizations/year and 18.1 very severe RSV disease/year in infants < 1 year of age. RSV vaccine could prevent 46.1 of hospitalizations/year caused by RSV within 180 days after birth.ConclusionsOur study contributes to outlining the baseline profile of RSV-associated hospitalizations among Italian children by providing epidemiological/clinical/economic estimates. While awaiting new recommendations on immunization, healthcare-workers should persist in implementing public health measures and appropriate case management to control RSV seasonal epidemics. Strengthened laboratory RSV surveillance is needed to inform the implementation of the new immunization strategies.

Prevalence of Influenza Viruses A and B, Adenovirus, Respiratory Syncytial Virus, and Human Metapneumonia Viruses among Children with Acute Respiratory Tract Infection.

Acute respiratory tract infection (ARTI) is a significant cause of morbidity and mortality among children worldwide. The majority of acute respiratory infections in children are caused by viruses, with respiratory syncytial virus (RSV) being the most frequently encountered. Other important viral pathogens include human metapneumovirus, human coronaviruses, adenovirus, and influenza. These infections can lead to complications such as bronchitis and pneumonia. So, this study aimed to evaluate the prevalence of influenza viruses A and B, adenovirus, respiratory syncytial virus (RSV), and human metapneumovirus (HMPV) in children with ARTI. The molecular diagnostic of polymerase chain reaction approach was used to detect influenza (A and B), metapneumovirus, respiratory syncytial virus (RSV), and adenovirus in respiratory samples of children with acute respiratory infection hospitalization in a teaching hospital of the Shiraz University of Medical Sciences in January 2016-March 2017. Of the 340 patients examined, 208 (61.20%) were male and the median age was 3.13 ± 2.38 years. Respiratory viruses were found in 179 (52.64%) patients. The male-to-female ratio was 1.63 : 1 in patients who were viral positive. Detection rates for influenza A, adenovirus, influenza B, RSV, and HMPV were 28.23%, 24.70%, 8.52%, 3.23%, and 2.64%, respectively, and coinfections were detected in 24.02%. The most common combination of two-virus coinfections was IFVA/AdV, followed by IFVB/AdV, AdV, IFVB/IFVA, RSV/IFVA, HMPV/AdV, RSV/AdV, and HMPV/IFVA. The high prevalence of respiratory viruses in children hospitalized with ARTI suggests that viral infection may play a role in disease pathogenesis. This should be confirmed through the conduct of case-control studies and may inform the role of vaccination to prevent respiratory viral infections.

260. Durability of Antibody Responses to RSV in Older Adults Following Hospitalization for Acute Respiratory Infection

Abstract Background Respiratory syncytial virus (RSV) is a common viral pathogen identified in older adults with acute respiratory infections (ARIs). Data describing the durability of immune responses to RSV are limited but suggest responses may be short-lived. In this study, we assessed longitudinal antibody responses following RSV-associated hospitalization for 3 years. Methods Between September 2018 and March 2020, adults ≥ 50 years of age hospitalized with ARI at two Emory University hospitals who had a positive RSV test via PCR were enrolled. A nasopharyngeal swab, oropharyngeal swab, and 10mL blood were collected at enrollment (V1), 30 days after enrollment (V2), and in the 4 weeks prior to the start of the influenza season(s) for three years after enrollment (1 yr, 2 yr, 3 yr). Syndrome-positive, RSV-negative controls were also enrolled. Serum samples were analyzed for RSV A/B lysate antigen by enzyme-linked immunosorbent assay (ELISA) and end-point titers were interpolated to a standard curve. Geometric mean titers (GMTs) were calculated, and statistical comparisons of log-transformed titers were performed using a mixed effects model in GraphPad Prism v9.0. Results Of the 30 enrolled participants who completed follow-up, there were 20 RSV-positive cases and 10 controls (Table 1). Of these, 22 (73%) were female, 22 (73%) Black, and 30 (100%) non-Hispanic ethnicity. Baseline demographics were similar in cases and controls. However, being immunocompromised was more common in cases, and heart disease was more common in controls. Peak antibody titers were observed in cases at V2 (IgG GMT 642,685), and these declined non-significantly prior to the start of the next RSV season (IgG GMT 396,059, P=0.1306) (Figure 1). Titers then declined significantly 2 years (IgG GMT 134,836, P=0.0003) and 3 years (IgG GMT 117,729, P&amp;lt; 0.0001) after infection. RSV IgG GMTs were not significantly different between cases and controls at any time point. Results were similar when immunocompromised participants were excluded from the analysis.Table 1.Baseline characteristics of study cohort. Figure 1.RSV IgG antibody titers by ELISA in (A) Cases vs. Controls; (B) change in titer over time in Cases; and (C) change in titer over time in Controls. Conclusion RSV antibody responses peaked in early convalescence and persisted for 3 years after RSV-associated hospitalization. Antibody titers were similarly elevated in cases and controls, indicating the durability of RSV antibodies in older adults. Disclosures Elizabeth Begier, M.D, M.P.H., Pfizer: EB is an employee of Pfizer, the sponsor of this study|Pfizer: Stocks/Bonds Robin Hubler, MS, Pfizer, Inc.: Employee|Pfizer, Inc.: Stocks/Bonds Qing Liu, M.S., Pfizer Inc.: Stocks/Bonds Bradford D. Gessner, M.D, M.P.H., Pfizer: I am an employee of Pfizer|Pfizer: Stocks/Bonds Benjamin Lopman, PhD, Epidemiological Research and Methods, LLC: Advisor/Consultant|Hillevax, Inc: Advisor/Consultant Nadine Rouphael, MD, Icon, EMMES, Sanofi, Seqirus, Moderna: Advisor/Consultant Satoshi Kamidani, MD, CDC: Grant/Research Support|Emergent BioSolutions: Grant/Research Support|NIH: Grant/Research Support|Pfizer Inc: Grant/Research Support Evan J. Anderson, MD, GSK: Advisor/Consultant|GSK: Grant/Research Support|Janssen: Advisor/Consultant|Janssen: Grant/Research Support|Kentucky Bioprocessing, Inc.: Safety Monitoring Board|Moderna: Advisor/Consultant|Moderna: Grant/Research Support|Moderna: Currently an employee|Moderna: Stocks/Bonds|Pfizer: Advisor/Consultant|Pfizer: Grant/Research Support|Sanofi Pasteur: Advisor/Consultant|Sanofi Pasteur: Grant/Research Support|Sanofi Pasteur: Safety Monitoring Board|WCG/ACI Clinical: Data Adjudication Board Christina A. Rostad, MD, BioFire Inc.: Grant/Research Support|GlaxoSmithKline Biologicals: Grant/Research Support|Janssen: Grant/Research Support|MedImmune LLC: Grant/Research Support|Meissa Vaccines, Inc.: RSV vaccine technology|Merck &amp; Co., Inc.: Grant/Research Support|Micron Technology, Inc.: Grant/Research Support|Moderna, Inc.: Grant/Research Support|Novavax: Grant/Research Support|PaxVax: Grant/Research Support|Pfizer, Inc.: Grant/Research Support|Regeneron: Grant/Research Support|Sanofi Pasteur: Grant/Research Support

Molecular detection of Mycoplasma pneumoniae in respiratory samples from hospitalized children

It is currently reported that Mycoplasma pneumoniae (MP) infection can occur at a young age. Objective: Describe the findings of the molecular detection of MP in respiratory secretions of patients who required hospitalization due to acute respiratory infection, in a pediatric hospital. Data collection was performed by reviewing medical records and statistical correlation using the chi-square test. 919 patients from one month to fourteen years and eleven months of age who required hospitalization for acute respiratory infection were included. The frequency by age and sex of the isolation of MP was analyzed together with other respiratory pathogens. Mycoplasma pneumoniae was the most frequently detected microorganism (30%), followed by respiratory syncytial virus (RSV) (25.1%). Age and sex did not behave as a predictor of detection for MP. In 47.3% of the patients, MP was isolated together with another pathogen, the most prevalent was RSV 31.3%. Regarding the diagnoses at discharge of the group of patients with isolation of MP and a another microorganism, 50.8% had bronchiolitis, and in the group of patients with identification only of MP this percentage was 32.4%. The difference in the distributions was statistically significant (p <0.05). We conclude that Mycoplasma pneumoniae detection is frequent in our environment and occurs in a significant number of cases together with another respiratory pathogen. These findings should prompt further study to determine their clinical relevance.

1908. Social Risk Factors for COVID-19-Related Hospitalizations in Adults

Abstract Background During the COVID-19 pandemic, social interventions such as social distancing and mask wearing have been encouraged. Social risk factors for SARS-CoV-2 infection and subsequent hospitalization remain uncertain. Methods Adult patients were eligible if admitted to Emory University Hospital or Emory University Hospital Midtown with acute respiratory infection (ARI) symptoms (≤ 14 days) or an admitting ARI diagnosis from May 2021 – Feb 2022. After enrollment, an in-depth interview identified demographic and social factors (e.g., employment status, smoking history, alcohol use), household characteristics, and pandemic social behaviors. All patients were tested for SARS-CoV-2 using PCR. We evaluated whether these demographic and social factors were related to a positive SARS-CoV-2 test upon admission to hospital with ARI using a logistic regression model. Results 1141 subjects were enrolled and had SARS-CoV-2 PCR results available (700 positive and 441 negative). The median age was greater in the SARS-CoV-2 negative cohort than in the positive cohort (60 and 53 years, respectively; P&amp;lt; .0001). Those who tested positive were more likely to have had at least some college education compared to those who tested negative (64.3% vs 52.3%, P&amp;lt; .0001; adjusted odds ratio [aOR]: 1.4 [95%CI: 1.1, 2.0]). Compared to those who tested negative, those who were SARS-CoV-2 positive were also more likely to be employed (48.9% vs 26.5%, P&amp;lt; .0001; aOR: 1.7 [95%CI: 1.1, 2.3]), have children 5-17 yo at home (27.6% vs 17.9%, P=.0002; aOR: 1.5 [95%CI: 1.1, 2.1]). Those with COVID-19 were less likely to receive home healthcare (6.2% vs 13.3%, P&amp;lt; .0001; aOR: 0.5 [95%CI: 0.4, 0.9]) and to be a current or previous smoker (7.6% vs 17.7%, P&amp;lt; .0001; aOR: 0.3 [95%CI: 0.2, 0.5]). Conclusion Among adults admitted to the hospital for ARI, those who tested positive for SARS-CoV-2 were typically younger, more likely to care for school-aged children, more likely to work outside the home, but were less likely to receive home healthcare or smoke. Personal and public health strategies to mitigate COVID-19 should take into consideration modifiable social risk factors. Disclosures Laura A. Puzniak, PhD. MPH, Merck &amp; Co., Inc.: Stocks/Bonds|Pfizer, Inc.: Stocks/Bonds Robin Hubler, MS, Pfizer Inc.: Employee|Pfizer Inc.: Stocks/Bonds Srinivas Valluri, PhD, Pfizer: Employee|Pfizer: Stocks/Bonds Benjamin Lopman, PhD, Epidemiological Research and Methods, LLC: Advisor/Consultant Satoshi Kamidani, MD, NIH: His institution (Emory University) receives funds from Pfizer for his work as a co-investigator on clinical trials of Pfizer COVID-19 vaccine.|Pfizer: His institution (Emory University) receives funds from Pfizer for his work as a co-investigator on clinical trials of Pfizer COVID-19 vaccine. Christina A. Rostad, MD, BioFire Inc, GSK, MedImmune, Micron, Merck, Novavax, PaxVax, Pfizer, Regeneron, Sanofi-Pasteur.: Grant/Research Support|Meissa Vaccines, Inc.: Co-inventor of RSV vaccine technology licensed to Meissa Vaccines, Inc.|NIH (Funding from NIH to conduct clinical trials of Moderna and Janssen COVID-19 vaccines): Grant/Research Support John M. McLaughlin, PhD, Pfizer: Employee|Pfizer: Stocks/Bonds Evan J. Anderson, MD, GSK: Advisor/Consultant|GSK: Grant/Research Support|Janssen: Advisor/Consultant|Janssen: Grant/Research Support|Kentucky Bioprocessing, Inc: Data Safety Monitoring Board|MedImmune: Grant/Research Support|Medscape: Advisor/Consultant|Merck: Grant/Research Support|Micron: Grant/Research Support|NIH: Funding from NIH to conduct clinical trials of Moderna and Janssen COVID-19 vaccines|PaxVax: Grant/Research Support|Pfizer: Advisor/Consultant|Pfizer: Grant/Research Support|Regeneron: Grant/Research Support|Sanofi Pasteur: Advisor/Consultant|Sanofi Pasteur: Grant/Research Support|Sanofi Pasteur: Data Adjudication and Data Safety Monitoring Boards|WCG and ACI Clinical: Data Adjudication Board.

Urgent air transfers for acute respiratory infections among children from Northern Canada, 2005-2014.

BackgroundThe incidence of hospitalizations for acute respiratory infections (ARI) among young Indigenous children from Northern Canada is consistently high. ARIs requiring urgent air transfer can be life-threatening and costly. We aimed to describe their epidemiology, estimate age-specific incidences, and explore factors associated with level of care required.MethodsWe undertook a retrospective cohort study of children <5 years old from Northern Canada transferred by urgent air transport for ARI from 2005 through 2014 to 5 pediatric tertiary care centers in Vancouver, Edmonton, Winnipeg, Ottawa and Montreal. Admissions were identified via ARI-related ICD-9/10 coding and forward sortation area. Descriptive statistics and univariable analyses were performed.ResultsAmong 650 urgent air transfers, the majority were from Nunavut (n = 349, 53.7%) or Nunavik (n = 166, 25.5%), <6 months old (n = 372, 57.2%), and without underlying comorbidity (n = 458; 70.5%). Estimated annual tertiary care ARI admission rates in infants <1 year old from Nunavut (40.7/1000) and Nunavik (44.5/1000) were tenfold higher than in children aged 1 to 4 years. Bronchiolitis (n = 333, 51.2%) and pneumonia (n = 208, 32.0%) were the most common primary discharge diagnoses. Nearly half required critical care (n = 316, 48.6%); mechanical ventilation rates ranged from 7.2% to 55.9% across centres. The most common primary pathogen was respiratory syncytial virus (n = 196, 30.1%). Influenza A or B was identified in 35 cases (5.4%) and vaccine-preventable bacterial infections in 27 (4.1%) cases.InterpretationUrgent air transfers for ARI from Northern Canada are associated with high acuity. Variations in levels of care were seen across referral centers, age groups and pathogens.

Estimating the burden of adult hospitalized RSV infection using local and state data - methodology

ABSTRACT Respiratory syncytial virus (RSV) is becoming increasingly recognized as a serious threat to vulnerable population subgroups. This study describes the statistical analysis plan for a retrospective cohort study of adults hospitalized for acute respiratory infection (ARI) to estimate the population burden of RSV especially for groups such as the elderly, pregnant women and solid organ transplant patients. Disease burden estimates are essential for setting vaccine policy, e.g., should RSV vaccine become available, burden estimates may inform recommendations to prioritize certain high-risk groups. The study population is residents of Allegheny County, Pennsylvania ≥18 years of age who were hospitalized in Pennsylvania during the period September 1, 2015–August 31, 2018. Data sources will include U.S. Census, Pennsylvania Health Care Cost Containment Council (PHC4) and the electronic medical record for the health system to which the hospitals belong. The algorithm involves: 1) ARI-associated hospitalizations in PHC4 data; 2) adjustment for ARI hospitalizations among county residents but admitted to hospitals outside the county; and 3) RSV detections from respiratory viral panels. Key sensitivity analyses will adjust for undertesting for viruses in the fall and spring quarters. The results will be population-based estimates, stratified by age and risk groups. Adjusting hospitalization data using a multiplier method is a simple means to estimate the impact of RSV in a given area. This algorithm can be applied to other health systems and localities to estimate RSV and other respiratory pathogen burden in adults, to estimate burden following introduction of RSV vaccine and to make cost-effectiveness estimates.

Respiratory Syncytial Virus Outbreak Without Influenza in the Second Year of the Coronavirus Disease 2019 Pandemic: A National Sentinel Surveillance in Korea, 2021-2022 Season.

BackgroundThis study aimed to investigate whether respiratory syncytial virus (RSV) and influenza virus (IFV) infections would occur in 2021–2022 as domestic nonpharmaceutical interventions (NPIs) are easing.MethodsData were collected from the Korean Influenza and Respiratory Virus Monitoring System database. The weekly positivity rates of respiratory viruses and number of hospitalizations for acute respiratory infections were evaluated (January 2016–2022). The period from February 2020 to January 2022 was considered the NPI period. The autoregressive integrated moving average model and Poisson analysis were used for data analysis. Data from 14 countries/regions that reported positivity rates of RSV and IFV were also investigated.ResultsCompared with the pre-NPI period, the positivity and hospitalization rates for IFV infection during 2021–2022 significantly decreased to 0.0% and 1.0%, respectively, at 0.0% and 1.2% of the predicted values, respectively. The RSV infection positivity rate in 2021–2022 was 1.8-fold higher than that in the pre-NPI period at 1.5-fold the predicted value. The hospitalization rate for RSV was 20.0% of that in the pre-NPI period at 17.6% of the predicted value. The re-emergence of RSV and IFV infections during 2020–2021 was observed in 13 and 4 countries, respectively.ConclusionDuring 2021–2022, endemic transmission of the RSV, but not IFV, was observed in Korea.

Burden of Influenza-Associated Respiratory Hospitalizations, Vietnam, 2014-2016.

Influenza burden estimates are essential to informing prevention and control policies. To complement recent influenza vaccine production capacity in Vietnam, we used acute respiratory infection (ARI) hospitalization data, severe acute respiratory infection (SARI) surveillance data, and provincial population data from 4 provinces representing Vietnam’s major regions during 2014–2016 to calculate provincial and national influenza-associated ARI and SARI hospitalization rates. We determined the proportion of ARI admissions meeting the World Health Organization SARI case definition through medical record review. The mean influenza-associated hospitalization rates per 100,000 population were 218 (95% uncertainty interval [UI] 197–238) for ARI and 134 (95% UI 119–149) for SARI. Influenza-associated SARI hospitalization rates per 100,000 population were highest among children <5 years of age (1,123; 95% UI 946–1,301) and adults >65 years of age (207; 95% UI 186–227), underscoring the need for prevention and control measures, such as vaccination, in these at-risk populations.

Quantifying dose-, strain-, and tissue-specific kinetics of parainfluenza virus infection.

Human parainfluenza viruses (HPIVs) are a leading cause of acute respiratory infection hospitalization in children, yet little is known about how dose, strain, tissue tropism, and individual heterogeneity affects the processes driving growth and clearance kinetics. Longitudinal measurements are possible by using reporter Sendai viruses, the murine counterpart of HPIV 1, that express luciferase, where the insertion location yields a wild-type (rSeV-luc(M-F*)) or attenuated (rSeV-luc(P-M)) phenotype. Bioluminescence from individual animals suggests that there is a rapid increase in expression followed by a peak, biphasic clearance, and resolution. However, these kinetics vary between individuals and with dose, strain, and whether the infection was initiated in the upper and/or lower respiratory tract. To quantify the differences, we translated the bioluminescence measurements from the nasopharynx, trachea, and lung into viral loads and used a mathematical model together a nonlinear mixed effects approach to define the mechanisms distinguishing each scenario. The results confirmed a higher rate of virus production with the rSeV-luc(M-F*) virus compared to its attenuated counterpart, and suggested that low doses result in disproportionately fewer infected cells. The analyses indicated faster infectivity and infected cell clearance rates in the lung and that higher viral doses, and concomitantly higher infected cell numbers, resulted in more rapid clearance. This parameter was also highly variable amongst individuals, which was particularly evident during infection in the lung. These critical differences provide important insight into distinct HPIV dynamics, and show how bioluminescence data can be combined with quantitative analyses to dissect host-, virus-, and dose-dependent effects.

Effect of in-house crowding on childhood hospital admissions for acute respiratory infection: A matched case–control study in Bangladesh

ObjectiveDespite previous studies conducted to identify potential household factors, no conclusive evidence exists regarding the effect of in-house crowding on hospitalization for acute respiratory infection (ARI) in Bangladesh. Hence, the aim of this study was to detect such an association in children aged 6–59 months. MethodsAn age and sex-matched case–control study was conducted involving 348 children in Bangladesh. In-house crowding was measured by people-per-bedroom. Conditional logistic regression was performed to identify the association between in-house crowding and hospitalization for ARI. ResultsIn-house overcrowding was associated with a 2.9-fold (95% confidence interval 1.80–4.73) greater adjusted odds of hospitalization for ARI compared to children from less crowded houses. In-house overcrowding was common in rural areas and in households with a poor economic status. Suboptimal breastfeeding and household tobacco smoke exposure were found to prevail in overcrowded households. ConclusionIn-house overcrowding is associated with an increased risk of hospitalization for ARI in young children. Eliminating the fraction of the ARI burden due to in-house overcrowding will rely on increasing awareness regarding indoor air pollution and ventilation in the house and making efforts to avoid smoking in dwellings. Along with the management of crowding, child nutrition and exclusive breast-feeding requirements should be continued for a wide range of child health benefits.

Relative Severity of Common Human Coronaviruses and Influenza in Patients Hospitalized With Acute Respiratory Infection: Results From 8-Year Hospital-Based Surveillance in Quebec, Canada.

BackgroundFew data exist about the role of common human coronaviruses (HCoV) in patients hospitalized for acute respiratory illness (ARI) and the severity of these infections compared to influenza.MethodsProspective data on virus etiology of ARI hospitalizations during the peaks of 8 influenza seasons (2011-12 to 2018-19) in Quebec, Canada, was used to compare patients with HCoV to those with influenza infections; generalized estimation equations models were used for multivariate analyses.ResultsWe identified 340 HCoV infections which affected 11.6%(n=136) of children and 5.2%(n=204) of adults hospitalized with ARI. The majority of children (75%) with HCoV infections were also coinfected with other respiratory viruses compared to 24% of the adults (p<0.0001). No deaths were recorded in children; 5.8% of adults with HCoV monoinfection compared to 4.2% of those with influenza monoinfection died (p=0.226). The risk of pneumonia was non-significantly lower in children with HCoV than with influenza but similarly high in adults. Markers of severity (length-of-stay, intensive-care admissions and case-fatality ratio) were comparable between these infections in multivariate analyses, both in children and adults.ConclusionsIn children and adults hospitalized with ARI, HCoV infections were less frequent than influenza infections, but HCoV monoinfections were as severe as influenza monoinfections.

The health and economic burden of respiratory syncytial virus associated hospitalizations in adults.

Respiratory syncytial virus (RSV) is increasingly recognized as an important cause of illness in adults; however, data on RSV disease and economic burden in this age group remain limited. We aimed to provide comprehensive estimates of RSV disease burden among adults aged ≥18 years. During 2012-2015, population-based, active surveillance of acute respiratory infection (ARI) hospitalizations enabled estimation of the seasonal incidence of RSV hospitalizations and direct health costs in adults aged ≥18 years in Auckland, New Zealand. Of 4,600 ARI hospitalizations tested for RSV, 348 (7.6%) were RSV positive. The median (interquartile range) length of hospital stay for RSV positive patients was 4 (2-6) days. The seasonal incidence rate (IR) of RSV hospitalizations, corrected for non-testing, was 23.6 (95% confidence intervals [CI] 21.0-26.1) per 100,000 adults aged ≥18 years. Hospitalization risk increased with age with the highest incidence among adults aged ≥80 years (IR 190.8 per 100,000, 95% CI 137.6-244.0). Being of Māori or Pacific ethnicity or living in a neighborhood with low socioeconomic status (SES) were independently associated with increased RSV hospitalization rates. We estimate RSV-associated hospitalizations among adults aged ≥18 years to cost on average NZD $4,758 per event. RSV infection is associated with considerable disease and economic cost in adults. RSV disproportionally affects adult sub-groups defined by age, ethnicity, and neighborhood SES. An effective RSV vaccine or RSV treatment may offer benefits for older adults.

Cost-effectiveness of introducing national seasonal influenza vaccination for adults aged 60\xa0years and above in mainland China: a modelling analysis

BackgroundChina has an aging population with an increasing number of adults aged ≥ 60 years. Influenza causes a heavy disease burden in older adults, but can be alleviated by vaccination. We assessed the cost-effectiveness of a potential government-funded seasonal influenza vaccination program in older adults in China.MethodsWe characterized the health and economic impact of a fully funded influenza vaccination program for older adults using China-specific influenza disease burden, and related cost data, etc. Using a decision tree model, we calculated the incremental costs per quality-adjusted life year (QALY) gained of vaccination from the societal perspective, at a willingness-to-pay threshold equivalent to GDP per capita (US$8840). Moreover, we estimated the threshold vaccination costs, under which the fully funded vaccination program is cost-effective using GDP per capita as the willingness-to-pay threshold.ResultsCompared to current self-paid vaccination, a fully funded vaccination program is expected to prevent 19,812 (95% uncertainty interval, 7150–35,783) influenza-like-illness outpatient consultations per year, 9418 (3386–17,068) severe acute respiratory infection hospitalizations per year, and 8800 (5300–11,667) respiratory excess deaths due to influenza per year, and gain 70,212 (42,106–93,635) QALYs per year. Nationally, the incremental costs per QALY gained of the vaccination program is US$4832 (3460–8307), with a 98% probability of being cost-effective. The threshold vaccination cost is US$10.19 (6.08–13.65). However, variations exist between geographical regions, with Northeast and Central China having lower probabilities of cost-effectiveness.ConclusionsOur results support the implementation of a government fully funded older adult vaccination program in China. The regional analysis provides results across settings that may be relevant to other countries with similar disease burden and economic status, especially for low- and middle-income countries where such analysis is limited.

Acute respiratory infection and its associated factors among children under-five years attending pediatrics ward at University of Gondar Comprehensive Specialized Hospital, Northwest Ethiopia: institution-based cross-sectional study

BackgroundAcute respiratory infection is manifested by cough accompanied by short rapid breathing which may be associated with death especially when there are other co-morbidities. From an estimated 5.4 million children under –five years that died in 2017—roughly half of those deaths occurred in sub-Saharan Africa and acute respiratory infection contributed to the highest number of deaths. The current study aimed at evaluating the prevalence of, and risk factors associated with, acute respiratory infection hospitalization in under-five years children hospitalized at the University of Gondar Comprehensive Specialized Hospital.MethodAn institution-based cross-sectional study was carried out from May 01/2019 to July 10/2019. After the selection of participants using simple random sampling, face to face interview was performed using a semi-structured pre-tested questionnaire. Data were also extracted from medical registration charts. We used EPI Info 7 for data entry and exported into SPSS 21 for analysis. Results were presented by simple frequency, percentage and mean for descriptive variables. Binary logistic regression analysis was used to test the association of covariates and outcome variable. Variables with a p < 0.2 during the bivariable binary logistic regression analysis were included in the multivariable logistic regression analysis. Variables with p < 0.05 were considered as significantly associated with acute respiratory infection. This study is reported following the Strengthening the Reporting of Observational Studies in Epidemiology guideline.ResultsFour hundred and twenty-two under-five years’ children attending the Pediatrics ward were included in this study. The prevalence of acute respiratory infection among under-five years’ children in this study was 27.3%. Children aged below 12 months (AOR:3.39, 95% CI: 1.19, 9.65), maternal age of 16 to 27 years (AOR: 1.95, 95% CI: 1.03, 3.70), maternal age of 28 to 33 years (AOR: 2.73, 95% CI: 1.40, 5.34), lack of maternal awareness of handwashing (AOR: 2.79, 95% CI: 1.15, 6.76), rural residence (AOR:2.27, 95% CI: 1.18, 4.39), and lack of meningitis (AOR: 0.22, 95% CI: 0.08, 0.55), were significantly associated with acute respiratory infection.ConclusionAcute respiratory infection was common among children under-five years. Child and maternal age, residence and maternal hand hygiene information were significant factors identified to be associated with an acute respiratory infection.

Respiratory syncytial virus acute respiratory infection-associated hospitalizations in preterm Mexican infants: A cohort study.

BackgroundRespiratory syncytial virus (RSV) is the leading cause of severe acute respiratory infections (ARI) in preterm infants. The incidence of RSV‐associated hospitalizations has not been defined in Mexico.ObjectivesTo determine the incidence of ARI‐ and RSV‐associated hospitalizations in preterm infants during the first year of life.MethodsProspective cohort study of 294 preterm infants followed up through monthly telephone calls and routine outpatient visits. Hospitalized children were identified through daily visits to pediatric wards of participating hospitals and through telephone calls. Respiratory samples were tested for RSV by RT‐PCR.ResultsMean gestational age of participating infants was 33 weeks. Ninety‐six infants were diagnosed with bronchopulmonary dysplasia (BPD) and 17 with congenital heart disease (CHD); 11 had both conditions. There were 71 hospitalization episodes in 53 infants. Respiratory samples for RSV detection were available in 44 hospitalization episodes, and the result was positive in 16 (36.3%). At least one hospitalization for ARI was recorded in 33 of 96 participants with BPD, in seven of 17 with CHD, and 18 of 192 infants without these diagnoses. Five (71.4%) of CHD infants who required admission also had BPD. RSV‐confirmed hospitalization rates were 9.4%, 5.9%, and 2.6% for infants with BPD, CHD, and otherwise healthy preterm infants, respectively. Attributable RSV admission frequencies were estimated to be 13.6%, 16.5%, and 4.1%, respectively.ConclusionsMexican preterm infants, particularly those with BPD, have high rates of ARI‐ and RSVassociated hospitalizations. Specific interventions to reduce the incidence of severe infections in this highrisk group are required.