Why 90% of Children Dying From Flu This Season Were Unvaccinated

The 2024-25 flu season has claimed 66 children's lives so far, with a troubling pattern emerging: 90% of pediatric deaths occurred in children who were eligible for vaccination but remained unvaccinated. This statistic underscores a critical vulnerability in America's youngest population as flu activity remains moderate to very high across most regions of the country.

How Bad Is This Flu Season for Children?

The numbers paint a sobering picture. The current respiratory illness season has already surpassed historical norms for pediatric flu deaths. The 2024-25 season saw 289 pediatric deaths—the most reported in a non-pandemic flu season since the Centers for Disease Control and Prevention (CDC) began tracking child flu deaths in 2004. To put this in perspective, children have proven particularly vulnerable to severe illness this year, while both adults and older adults are experiencing moderate-severity disease.

Beyond deaths, the burden on healthcare systems is mounting. Last week alone, six more children died from influenza, bringing the season total to 66 pediatric deaths. The cumulative flu hospitalization rate reached 67.0 per 100,000 people, with 14,656 people admitted to hospitals in just one week. Flu test positivity climbed to 18.6%, and outpatient visits for respiratory illness reached 4.6%, indicating the virus continues spreading rapidly across communities.

What's Driving the Vaccine Gap Among Vulnerable Children?

The vaccination disparity is striking. Of all pediatric deaths this season, 90% of those who were eligible for the flu vaccine had not received it. This gap matters because the flu vaccine, while not perfect, significantly reduces the risk of severe illness and death in children. The current season has seen cumulative totals of 23 million illnesses, 300,000 hospitalizations, and 19,000 deaths across all age groups, yet vaccination rates among eligible children remain concerningly low.

Several factors contribute to this protection gap:

• Vaccine Effectiveness Challenges: The current flu vaccine shows modest effectiveness against this season's dominant strains, with 40% effectiveness against medically attended infection with influenza A(H3N2) viruses and 37% against the subclade K variant of H3N2, which carries mutations that allow it to partially evade immunity from the vaccine.
• Strain Dominance Shift: Influenza A activity is declining at 67.2%, while influenza B has been rising in most areas over the past three weeks, now accounting for 32.8% of cases, creating a moving target for vaccine formulation.
• Parental Hesitancy: Despite the clear evidence of severe illness in unvaccinated children, vaccination uptake remains below optimal levels, suggesting ongoing concerns or misinformation about vaccine safety among some families.

The genetic characterization of influenza A viruses adds another layer of complexity. Of 1,126 collected influenza A viruses that underwent additional genetic characterization since late September, 92% were the subclade K variant, which contains mutations allowing it to partially skirt immunity conferred by the current flu vaccine formula. This means even vaccinated individuals face some risk, though vaccination still provides meaningful protection compared to being unvaccinated.

What Other Respiratory Viruses Are Circulating Right Now?

Influenza is not the only concern this respiratory season. Respiratory syncytial virus (RSV) levels are also high and growing in many parts of the country. Emergency department visits among children younger than one year and those aged one to four years are elevated, with hospital admissions highest among infants under one year old. COVID-19 rates remain elevated in some states, though emergency department visits for the virus are decreasing overall.

The CDC continues to expect that the fall and winter respiratory disease season will likely produce a similar number of combined peak hospitalizations due to COVID-19, influenza, and RSV compared to last season. This means healthcare systems should prepare for sustained pressure across multiple viral fronts rather than a single dominant threat.

The data sends a clear message to parents and caregivers: while no vaccine is 100% effective, the flu vaccine remains the best available tool to protect children from severe illness and death. With 90% of pediatric deaths occurring in unvaccinated eligible children, the choice to vaccinate carries profound implications for individual families and public health alike.