Epidemiological shift in neonatal viral lower respiratory tract infections during and after the COVID-19 pandemic: changes in pathogen dDistribution and clinical severity

Hasan Avşar; Ali Bülbül; Evrim Kıray Baş; Ahmet Yaşar Tellioğlu; Alper Divarcı; Hasan Sinan Uslu; Ebru Türkoğlu Ünal

Epidemiological shift in neonatal viral lower respiratory tract infections during and after the COVID-19 pandemic: changes in pathogen dDistribution and clinical severity

Abstract

Aims: To evaluate the impact of the COVID-19 pandemic on the epidemiology and clinical characteristics of viral lower respiratory tract infections (LRTIs) in young infants admitted to a neonatal intensive care unit (NICU). Methods: This single-center retrospective cohort study included 235 young infants hospitalized with viral LRTI between January 2018 and January 2024. Patients were categorized into pre-pandemic (n=54), during the pandemic (n=64), and post-pandemic (n=117) periods. Demographic characteristics, viral pathogen distribution, respiratory support requirements, length of stay, and clinical morbidities were compared. Multivariate logistic regression was performed to identify predictors of invasive mechanical ventilation (IMV). Results: RSV was the most frequently identified pathogen (49.8%), followed by SARS-CoV-2 (8.5%), influenza (6.4%), and rhinovirus (3.0%); no pathogen was detected in 24.7% of cases. Viral distribution differed significantly across pandemic periods (χ² test, p=0.017; Cramer’s V=0.35). RSV proportion increased from 40.7% (pre-pandemic) to 53.0% (post-pandemic), while SARS-CoV-2 emerged during the pandemic (20.3%). Respiratory support requirements differed significantly (p=0.002; Cramer’s V=0.22), with invasive ventilation decreasing from 50.0% (pre-pandemic) to 20.5% (post-pandemic). Length of NICU stay did not differ significantly among periods (p=0.354). Clinical morbidities were comparable across periods (all p>0.05). In multivariate analysis, RSV-related infection independently predicted IMV (OR 4.36, 95% CI 2.15-8.84, p<0.001). Compared with the pre-pandemic period, the odds of IMV was significantly lower during the pandemic (OR 0.38, 95% CI 0.17-0.87, p=0.022) and post-pandemic (OR 0.17, 95% CI 0.07-0.38, p<0.001). Conclusion: The COVID-19 pandemic was associated with significant changes in viral pathogen distribution in young infants viral LRTIs. Although RSV remained the predominant pathogen and independently increased odds of severe disease, overall invasive ventilation requirements declined during and after the pandemic. Ongoing young infants-specific viral surveillance and updated RSV preventive strategies are warranted.

Keywords

Ethical Statement

The study was approved by the Clinical Research Ethics Committee of the Health Sciences University Şişli Hamidiye Etfal Training and Research Hospital Date: 03 March 2024; Decision No: 4357).

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Details

Primary Language

English

Subjects

Pediatric Intensive Care

Journal Section

Research Article

Authors

Hasan Avşar ^*
0000-0003-0283-0457
Türkiye

Ali Bülbül
0000-0002-3510-3056
Türkiye

Evrim Kıray Baş
0000-0001-5230-8718
Türkiye

Ahmet Yaşar Tellioğlu
0000-0001-7531-1821
Türkiye

Alper Divarcı
0000-0001-8754-2504
Türkiye

Hasan Sinan Uslu
0000-0002-2004-0419
Türkiye

Ebru Türkoğlu Ünal
0000-0003-0171-7858
Türkiye

Publication Date

May 19, 2026

Submission Date

February 23, 2026

Acceptance Date

March 28, 2026

Published in Issue

Year 2026 Volume: 9 Number: 3

IZ

https://izlik.org/JA64WT32KK

Cite

RIS / Bibtex

APA

Avşar, H., Bülbül, A., Baş, E. K., Tellioğlu, A. Y., Divarcı, A., Uslu, H. S., & Ünal, E. T. (2026). Epidemiological shift in neonatal viral lower respiratory tract infections during and after the COVID-19 pandemic: changes in pathogen dDistribution and clinical severity. Journal of Health Sciences and Medicine, 9(3), 727-733. https://izlik.org/JA64WT32KK

AMA

1.Avşar H, Bülbül A, Baş EK, et al. Epidemiological shift in neonatal viral lower respiratory tract infections during and after the COVID-19 pandemic: changes in pathogen dDistribution and clinical severity. J Health Sci Med / JHSM. 2026;9(3):727-733. https://izlik.org/JA64WT32KK

Chicago

Avşar, Hasan, Ali Bülbül, Evrim Kıray Baş, et al. 2026. “Epidemiological Shift in Neonatal Viral Lower Respiratory Tract Infections During and After the COVID-19 Pandemic: Changes in Pathogen DDistribution and Clinical Severity”. Journal of Health Sciences and Medicine 9 (3): 727-33. https://izlik.org/JA64WT32KK.

EndNote

Avşar H, Bülbül A, Baş EK, Tellioğlu AY, Divarcı A, Uslu HS, Ünal ET (May 1, 2026) Epidemiological shift in neonatal viral lower respiratory tract infections during and after the COVID-19 pandemic: changes in pathogen dDistribution and clinical severity. Journal of Health Sciences and Medicine 9 3 727–733.

IEEE

[1]H. Avşar et al., “Epidemiological shift in neonatal viral lower respiratory tract infections during and after the COVID-19 pandemic: changes in pathogen dDistribution and clinical severity”, J Health Sci Med / JHSM, vol. 9, no. 3, pp. 727–733, May 2026, [Online]. Available: https://izlik.org/JA64WT32KK

ISNAD

Avşar, Hasan - Bülbül, Ali - Baş, Evrim Kıray - Tellioğlu, Ahmet Yaşar - Divarcı, Alper - Uslu, Hasan Sinan - Ünal, Ebru Türkoğlu. “Epidemiological Shift in Neonatal Viral Lower Respiratory Tract Infections During and After the COVID-19 Pandemic: Changes in Pathogen DDistribution and Clinical Severity”. Journal of Health Sciences and Medicine 9/3 (May 1, 2026): 727-733. https://izlik.org/JA64WT32KK.

JAMA

1.Avşar H, Bülbül A, Baş EK, Tellioğlu AY, Divarcı A, Uslu HS, Ünal ET. Epidemiological shift in neonatal viral lower respiratory tract infections during and after the COVID-19 pandemic: changes in pathogen dDistribution and clinical severity. J Health Sci Med / JHSM. 2026;9:727–733.

MLA

Avşar, Hasan, et al. “Epidemiological Shift in Neonatal Viral Lower Respiratory Tract Infections During and After the COVID-19 Pandemic: Changes in Pathogen DDistribution and Clinical Severity”. Journal of Health Sciences and Medicine, vol. 9, no. 3, May 2026, pp. 727-33, https://izlik.org/JA64WT32KK.

Vancouver

1.Hasan Avşar, Ali Bülbül, Evrim Kıray Baş, Ahmet Yaşar Tellioğlu, Alper Divarcı, Hasan Sinan Uslu, Ebru Türkoğlu Ünal. Epidemiological shift in neonatal viral lower respiratory tract infections during and after the COVID-19 pandemic: changes in pathogen dDistribution and clinical severity. J Health Sci Med / JHSM [Internet]. 2026 May 1;9(3):727-33. Available from: https://izlik.org/JA64WT32KK