CDC officials urge US flu vaccination after record child deaths last year

Health officials are strongly recommending that people get vaccinated against the flu and that doctors prescribe antiviral medications, following a year with a record high number of flu-related deaths in children. A new mutation of the virus is also circulating in the United States, raising concerns.

Dr. Timothy Uyeki, chief medical officer of the influenza division at the CDC, emphasized the urgency of vaccination in a recent call with clinicians. "Flu activity is increasing across the country, and now is the time to get vaccinated for this season," he stated.

The recommendation comes at a time when access to vaccines may be diminishing, and misinformation about their effectiveness is spreading. These concerns are amplified by the actions of Robert F Kennedy Jr., the secretary of the Department of Health and Human Services, who has made false claims about flu vaccines and has overseen restrictions on routine vaccinations.

CDC officials also stressed the importance of ongoing monitoring of flu variants, including the H3N2 virus subclade K, which is currently the dominant strain in the US. This emphasis follows a year of significant staff and program cuts at health agencies.

"It's difficult to predict the flu season's trajectory, highlighting the necessity of surveillance to track the virus," Uyeki explained.

Earlier this month, the CDC reported the first known pediatric flu death of the current season, occurring in the week ending November 22nd. Last year saw a total of 288 child deaths from the flu, making it the deadliest pediatric flu season on record outside of a pandemic year. Hospitalizations due to influenza last year were estimated to range from 610,000 to 1.3 million.

According to Uyeki, "Last season was severe by all measures, ranking among the most severe seasons the U.S. has experienced."

During the call, CDC officials also noted changes to vaccine policy, including a new recommendation against the use of thimerosal, a preservative previously used in a small percentage of flu vaccines. In June, the CDC's vaccine advisors voted to recommend only flu vaccines that are thimerosal-free.

The FDA has also announced changes to the approval process for flu vaccines, potentially requiring extensive annual trials for children and pregnant individuals. These changes could make annual vaccination more difficult to achieve.

Children, pregnant individuals, those with compromised immune systems, and the elderly are at the highest risk of severe illness and death from the flu. Vaccination helps protect against serious complications such as pneumonia, cardiac issues, neurological problems, and encephalopathy (brain dysfunction).

Last year, there were 109 cases of encephalopathy among children, with 74% requiring intensive care and 54% needing mechanical ventilation. A majority (55%) of these children had no underlying health conditions, except for not being vaccinated. Only 16% of eligible children had received the flu vaccine, and nearly one in five (19%) of those with encephalopathy died.

Uyeki stated that "The majority of these cases are preventable, making these deaths truly tragic."

He added, "This is the highest number of deaths for a seasonal influenza epidemic since records have been kept, underscoring the urgent need to improve flu prevention and reduce flu-related deaths in children across the United States."

Last year's flu vaccine was found to be 63% to 78% effective in preventing hospitalization among children and 41% to 55% effective among adults.

In August, the CDC identified a new flu variant, H3N2 virus subclade K, which mutated from the H3N2 version included in the current vaccine. This raises concerns about the vaccine's potential effectiveness this season.

That said, the reality is a bit more complicated. with the flu season just beginning in the US, there isn't enough data yet to accurately assess the vaccine's effectiveness against this new variant.

Lisa Grohskopf, a medical officer in the CDC's influenza division, explained, "It's too early to determine the precise impact of this new subclade on the influenza vaccine's effectiveness for this season."

She added that it takes time to accumulate enough data and specimens to calculate vaccine effectiveness.

Early data from the United Kingdom, which experienced an early flu season, suggests vaccine effectiveness of around 70% to 75% for children and 30% to 40% for adults, which is similar to previous years.

Grohskopf stated that the evidence indicates that "influenza vaccination remains an effective tool in preventing influenza-associated hospitalizations for the season."

She emphasized that the flu vaccine is recommended for everyone six months of age and older.

Healthcare providers are increasingly recommending FluMist for eligible patients, as its non-shot delivery method may reduce vaccine hesitancy. The FDA also recently approved a major change in September 2024, allowing FluMist to be administered at home by a caregiver or the patient.

Antiviral medications are also considered a safe and effective way to both treat and prevent severe flu illness, including during pregnancy. These medications are most effective when started early.

Uyeki noted a decline in flu antiviral prescriptions in recent years. Only 35% of high-risk children are prescribed antivirals, and only 32% of children who visit emergency departments due to the flu receive antiviral prescriptions.