Early influenza cases higher among children than adults

Children are more likely to experience symptoms and hospitalizations from influenza than adults during the current influenza season, according to a report from the Centers for Disease Control and Prevention.

Data was collected on influenza cases in Tennessee, which saw an early influenza season beginning in September 2022. In November 2022, high rates of hospitalizations were reported in pediatric patients. Following this rise in cases, data was evaluated from surveillance networks, patient surveys, and whole genome sequencing of influenza virus specimens.

Early influenza activity was examined in 14 of 95 Tennessee counties, using data from the Electronic Surveillance System for the Early Notification of Community-Based Epidemics (ESSENCE) and FluSurv-NET surveillance systems.

Information on emergency department visits for influenza-like illness(ILI-ED) was obtained through ESSENCE, while information on hospitalizations associated with influenza was obtained through FluSurv-NET. Data from October 2, 2022, to January 12, 2023, was analyzed.

While all age groups experienced influenza activity earlier than usual, hospitalizations among children aged under 5 years reached 12.6 per 100,000 individuals. These rates are similar to those seen during the peak of high-severity influenza seasons.

When examining patients tested for influenza at outpatient clinics, children were twice as likely to test positive than adults. Children were also twice as likely than adults to become ill through household contacts.

Overall, hospitalization rates from influenza reached high levels earlier than observed in recent influenza seasons. These rates were most common among pediatric patients, with 31% of ILI-ED visits in the week ending on November 26, 2022, being from this age group. Weekly pediatric hospitalizations approached the 98th percentile, which is considered very high intensity.

To reduce the risk of influenza infection, authors of the report advised individuals aged 6 months or older receive influenza vaccination, avoid contact with infected individuals, and take antivirals if recommended and prescribed.

Reference

Thomas CM, White EB, Kojima N, Fill MA, Hanna S, Jones TF, et al. Early and increased influenza activity among children — Tennessee, 2022–23 influenza season. MMWR Morb Mortal Wkly Rep. 2023;72:49–54. doi:10.15585/mmwr.mm7203a1