Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Comparative Study
. 2025 Mar 21;44(8):e278-e284.
doi: 10.1097/INF.0000000000004801.

Severe Influenza Virus Infection After COVID-19 Pandemic: Comparison of Influenza A and Influenza B

Affiliations
Comparative Study

Severe Influenza Virus Infection After COVID-19 Pandemic: Comparison of Influenza A and Influenza B

Nihal Akçay et al. Pediatr Infect Dis J. .

Abstract

Background: Influenza is a common cause of hospital admissions worldwide, and an increase in influenza cases has been observed following the COVID-19 pandemic. Our study investigated the epidemiological and clinical characteristics of pediatric patients with influenza infection admitted to pediatric intensive care units (PICUs) in Istanbul, Turkey, following the COVID-19 pandemic.

Methods: We conducted a retrospective study of pediatric patients with confirmed influenza infection who were admitted to 1 of the 11 PICUs in Istanbul, Turkey, between July 1, 2022, and June 30, 2024. Data on demographic characteristics, risk factors, clinical presentations, microbiological findings, complications and outcomes were systematically collected.

Results: A total of 108 children diagnosed with laboratory-confirmed influenza required admission to the PICUs. Sixty-five (60.2%) were diagnosed with influenza A and 43 (39.8%) patients were diagnosed with influenza B. Epidemiologic and clinical characteristics were similar in both influenza types, oxygen saturation was significantly higher in the influenza A group compared to the influenza B group. Severe neurological manifestations, including seizures and encephalitis, were significantly more common in the Influenza A group. In contrast, patients with Influenza B demonstrated a higher incidence of gastrointestinal symptoms, such as nausea, vomiting and abdominal pain. Pneumonia, sepsis and/or multiorgan dysfunction and liver failure were significantly higher in influenza B. Mortality was observed solely in the Influenza B group, with six patients resulting in death, corresponding to a mortality rate of 14%.

Conclusions: Influenza virus infection can cause serious multisystem complications such as acute respiratory distress syndrome and encephalitis. Influenza A can present with isolated or predominant neurological manifestations. Mortality may be more common in influenza B.

Keywords: children; critical care; influenza A; influenza B.

PubMed Disclaimer

Conflict of interest statement

The authors have no funding or conflicts of interest to disclose.

References

    1. Taubenberger JK, Morens DM. The pathology of influenza virus infections. Annu Rev Pathol. 2008;3:499–522.
    1. 2023-2024 influenza season summary: Influenza severity assessment, burden and burden prevented. Centers for Disease Control and Prevention; 2024. Available at: https://www.cdc.gov/flu/whats-new/flu-summary-addendum-2023-2024.html#:~... . Accessed January 1, 2025.
    1. Centers of Disease Control and Prevention. Preliminary estimated flu disease burden 2022–2023 flu season. Available at: https://www.cdc.gov/flu-burden/php/data-vis/2022-2023.html . Accessed January 3, 2025.
    1. T.C. Sağlik Bakanliği. “Aşi Takvimi.” and “Yetişkin Aşilama.” Available at: https://asi.saglik.gov.tr/asi/asi-kimlere-yapilir/liste/30-yeti%C5%9Fkin... and Available at: https://asi.saglik.gov.tr/asi-takvimi.html . Accessed January 4, 2025.
    1. Yehya N, Smith L, Thomas NJ, et al.; Second Pediatric Acute Lung Injury Consensus Conference (PALICC-2) of the Pediatric Acute Lung Injury and Sepsis Investigators (PALISI) Network. Definition, incidence, and epidemiology of pediatric acute respiratory distress syndrome: from the second pediatric acute lung injury consensus conference. Pediatr Crit Care Med. 2023;24:S87–S98.

Publication types

MeSH terms

LinkOut - more resources