Epidemiology of Respiratory Syncytial Virus Infections: Retrospective Data to Estimate the Disease Burden in Turkiye

Study type

• Study topic:
  Disease /health condition
• Study type:
  Non-interventional study
• Scope of the study:
  Disease epidemiology
• Data collection methods:
  Secondary use of data

Non-interventional study

• Non-interventional study design:
  Other
• Non-interventional study design, other:
  Retrospective analysis of pre-existing data

Study drug and medical condition

• Medical condition to be studied:
  Respiratory syncytial virus infection

Population studied

• Short description of the study population:
  The study will include 994 children under five years of age admitted to Acibadem hospitals across Turkey between 1 June 2022 and 1 June 2024 with laboratory-confirmed RSV disease.; ; The study population includes:; > Children with RSV-associated respiratory infections requiring outpatient, emergency department (ED), inpatient or intensive care unit (ICU) treatment.; > Infants with and without major risk factors including prematurity, congenital heart disease and congenital lung disease.; > Patients from 19 Acibadem hospitals, representing a diverse cross-section of paediatric RSV cases in different healthcare settings.; No exclusion criteria were defined for this study, providing a comprehensive assessment of the burden of RSV among hospitalised children in Turkey.
• Age groups:
  Neonate

  Preterm newborn infants (0 – 27 days)

  Term newborn infants (0 – 27 days)

  Infants and toddlers (28 days – 23 months)

  Children (2 to < 12 years)

Study design details

• Study design:
  This retrospective, multi-center study will analyze 994 children under 5 admitted to 19 Acibadem hospitals in Türkiye with laboratory-confirmed RSV from June 2022 to June 2024, assessing clinical features, severity, management, and outcomes of RSV cases.
• Main study objective:
  The main aim of this study is to comprehensively describe the clinical features, disease severity, treatment and outcomes in children under 5 years of age admitted to Acibadem hospitals in Turkey with laboratory-confirmed RSV disease. ; This includes analyses of baseline disease characteristics such as ICU admission, use of invasive and non-invasive ventilation and other resuscitation indicators.; ; Secondary objectives; Quantify RSV diagnostic testing and coding: To assess the frequency of RSV diagnostic testing and coding in hospitalised children focusing on identifying potential underdiagnosis of RSV, especially as diagnostic tests are not always covered in the outpatient setting, which may lead to missed diagnosis.; The proportion of RSV+ LRTI diagnoses: Determine the proportion of RSV-positive lower respiratory tract infections (LRTIs) among all LRTI diagnoses in outpatient, inpatient, intensive care unit and emergency department (ED) settings. This will provide insight into how often RSV is identified as a cause of LRTI in different healthcare settings.; Comparison of the burden of RSV: Compare the burden of RSV in children with and without major risk factors (e.g., preterm birth, congenital heart disease, chronic lung disease) to assess whether the burden of disease is greater for these children and whether outcomes are more severe.; comorbidities and complications: Assess comorbidities and complication rates in RSV patients, including assessing the need for interventions such as oxygen therapy, mechanical ventilation, or use of antibiotics and steroids.; Comparison with national data: Compare the study results with national-level data (e.g. from published studies or open-access databases) to get a broader picture of the burden of RSV in Turkey. This will include an assessment of RSV-related outpatient data, which are often under-represented in studies due to a lack of out-of-hospital testing coverage.
• Setting:
  Persons:; Children under 5 years of age who were admitted to Acibadem hospitals across Turkey with a laboratory-confirmed diagnosis of respiratory syncytial virus (RSV) between 1 June 2022 and 1 June 2024 were included in the study. The total number of participants was estimated at 994 children. The cohort included both healthy children and those with underlying risk factors such as premature birth, congenital heart defects, and chronic lung disease.; ; Location:; The study was conducted across 19 Acibadem hospitals located in various regions of Turkey. These hospitals represented a well-distributed sample, ensuring coverage of multiple geographical areas and a variety of clinical settings, including outpatient, emergency department (EU), inpatient, and intensive care unit (ICU) care.; ; Time Period:; Data were collected retrospectively from 1 June 2022 to 1 June 2024, covering a two-year period. This time frame ensured that relevant RSV cases were captured, accounting for the seasonal fluctuations in RSV incidence rates.; ; Selection Criteria:; > Inclusion Criteria: All children under 5 years of age who were admitted to Acibadem hospitals during the study period with a confirmed RSV diagnosis via laboratory tests were included.; > Exclusion Criteria: No exclusion criteria were defined, allowing the study to include the entire population of children hospitalized for RSV.; ; The study incorporated several clinical variables, including:; > Severity of illness, such as ICU hospitalization, ventilation type (invasive vs. non-invasive), and the need for additional treatments (e.g., oxygen therapy, antibiotics, steroids).; > Demographic information, including comorbidities and major risk factors (e.g., preterm birth, congenital heart disease).; ; RSV testing and coding frequency, which helped to identify underreporting or missed diagnoses in various clinical settings.
• Outcomes:
  Clinical Features; Medical Comorbidities and Birth History; RSV Testing and Coding Frequency; Palivizumab Immunoprophylaxis (if recorded); Emergency Unit/Outpatient Clinic Administration Ratios; Hospitalization and ICU Ratios; Interventions (including oxygen therapy, antibiotics, steroids, etc.); Investigations (blood analysis, chest radiograph, CT, lumbar puncture, etc.); Outcomes (hospitalization, length of stay, death)