Related Experiment Video
Updated: Oct 2, 2026
A Luciferase-fluorescent Reporter Influenza Virus for Live Imaging and Quantification of Viral Infection
Published on: August 14, 2019
Burden of interpandemic influenza in children younger than 5 years: a 25-year prospective study
Kathleen M Neuzil1, Yuwei Zhu, Marie R Griffin
1Division of Infectious Diseases, Department of Medicine, University of Washington School of Medicine, Seattle, Washington, USA. kneuzil@u.washington.edu
Insights
Influenza causes significant illness in young children, leading to many doctor visits and illnesses like ear infections and pneumonia. This study highlights the impact of influenza on children under five.
Area of Science:
- Pediatrics
- Infectious Diseases
- Vaccinology
Background:
- Respiratory viruses are a major cause of illness in young children.
- Influenza is a significant respiratory virus, but vaccines and treatments are available.
- Data on the incidence and impact of influenza in healthy young children is limited.
Purpose of the Study:
- To determine the incidence of laboratory-confirmed influenza illness in healthy children under five years old.
- To quantify the associated healthcare utilization and morbidity, including acute otitis media and lower respiratory tract disease.
- To assess the hospitalization rates for influenza-associated illnesses in this age group.
Main Methods:
- Prospective follow-up of 1665 healthy children aged under five years.
- Enrollment in the Vanderbilt Vaccine Clinic between 1974 and 1999.
- Collection of viral cultures during clinical illness to confirm influenzavirus infection.
Main Results:
- Influenza was associated with approximately 95 healthcare visits per 1000 children annually.
- An estimated 46 episodes of acute otitis media and 8 episodes of lower respiratory tract disease occurred per 1000 children yearly.
- Children under two years old experienced the highest rates of acute otitis media and lower respiratory tract disease, with 3-4 hospitalizations per 1000 children annually for influenza-associated conditions.
Conclusions:
- Influenza is a significant cause of morbidity in otherwise healthy children under five years old.
- The study quantifies the substantial burden of influenza, including doctor visits and secondary infections.
- Findings underscore the importance of influenza prevention strategies in young children.
Abstract:
Many respiratory viruses cause morbidity in young children, but a licensed vaccine and effective oral therapy are available only for influenzavirus. To determine the incidence of laboratory-confirmed influenza illness, we prospectively followed up 1665 healthy children aged <5 years who were enrolled in the Vanderbilt Vaccine Clinic at some point from 1974 through 1999. Viral cultures were obtained when the children presented with clinical illness. The isolation of influenzavirus was associated with an estimated 95 health care visits for children with symptoms of influenza, 46 episodes of acute otitis media, and 8 episodes of lower respiratory tract disease per 1000 children yearly. Rates of acute otitis media and lower respiratory tract disease were highest among children aged <2 years. Hospitalizations associated with culture-positive influenza occurred at an annual rate of 3-4 per 1000 children aged <2 years. Influenza is associated with substantial morbidity in otherwise healthy children aged <5 years.
