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Rapid Molecular Detection and Differentiation of Influenza Viruses A and B
Published on: January 30, 2017
Comparative Severity of Influenza A and B Infections in Hospitalized Children
Janna-Maija Mattila1, Tytti Vuorinen2,3, Terho Heikkinen1
1From the Department of Pediatrics, Turku University Hospital and University of Turku.
Insights
Influenza A and B infections show similar clinical severity in hospitalized children. Quadrivalent vaccines are recommended for optimal protection against severe influenza in children.
Area of Science:
- Pediatrics
- Infectious Diseases
- Virology
Background:
- Influenza A viruses are often considered more severe than influenza B viruses.
- Limited long-term studies compare the clinical severity of influenza A and B in pediatric hospitalizations.
Purpose of the Study:
- To compare the clinical severity and outcomes of influenza A and B infections in children.
- To evaluate management and treatment differences between influenza A and B in pediatric patients.
Main Methods:
- A retrospective analysis of 391 children under 16 hospitalized with confirmed influenza A or B.
- Data collected over a 14-year period (2004-2018) at Turku University Hospital, Finland.
- Comparisons performed across age groups (0-2, 3-9, 10-15 years) and overall.
Main Results:
- Influenza A (71.4%) was more common than influenza B (28.6%).
- No significant differences in clinical features, outcomes, ICU treatment, or length of stay were observed between influenza A and B.
- Similar rates of blood cultures and lumbar punctures were performed for both types.
Conclusions:
- Clinical severity of influenza A and B infections is comparable in children.
- Quadrivalent influenza vaccines, including both B lineages, are recommended for children to prevent severe illness.
Background:
Influenza A viruses are conventionally thought to cause more severe illnesses than B viruses, but few studies with long observation periods have compared the clinical severity of A and B infections in hospitalized children.
Methods:
We analyzed the clinical presentation, outcomes and management of all children <16 years of age admitted to Turku University Hospital, Finland, with virologically confirmed influenza A or B infection during the 14-year period of 1 July 2004 to 30 June 2018. All comparisons between influenza A and B were performed both within predefined age groups (0-2, 3-9 and 10-15 years) and in all age groups combined.
Results:
Among 391 children hospitalized with influenza A or B infection, influenza A was diagnosed in 279 (71.4%) and influenza B in 112 (28.6%) children. Overall, there were no significant differences in any clinical features or outcomes, management, treatment at intensive care unit or length of stay between children with influenza A and B, whether analyzed by age group or among all children. As indicators of the most severe clinical presentations, blood cultures were obtained from 101 (36.2%) children with influenza A and 39 (34.8%) with influenza B (P = 0.80), and lumbar puncture was performed to 16 (5.7%) children with influenza A and 11 (9.8%) children with influenza B (P = 0.15).
Conclusions:
The clinical severity of influenza A and B infections is similar in children. For optimal protection against severe influenza illnesses, the use of quadrivalent vaccines containing both lineages of B viruses seems warranted in children.
