Flu Vaccine Cuts Hospitalization In Kids Up To 78%- Is It Too Late To Your Shot?

As the 2024-2025 flu season continues, early data suggest that flu vaccines this year have significantly reduced hospitalizations and outpatient visits in vaccinated individuals. Public health experts highlight the value of flu vaccination, especially in light of the possible virulence of strains present this season. With attention on vaccine efficacy, the present situation of flu cases, and flu vaccination's future, here's what you should know.

Inital reports by the Centers for Disease Control and Prevention (CDC) indicate that the 2024-2025 flu vaccine has shown remarkable effectiveness in avert severe cases of the flu, especially among children. The findings, extracted from two healthcare center networks under the surveillance of the CDC, show that the vaccine has been as effective as 78% in averting hospitalization in children and teens.

For adults, the effectiveness of the vaccine in avoiding hospitalization has been between 41% and 55%. Furthermore, flu vaccines have decreased outpatient visits, such as doctor visits, urgent care, and emergency room visits. In children and adolescents, the effectiveness of the vaccine for outpatient visits was found to be 32%, 59%, and 60% in various healthcare networks, while in adults it was between 36% and 54%.

Despite variations in regional effectiveness, experts maintain that this year’s flu shots offer strong protection comparable to previous high-efficacy flu seasons over the last 15 years.

Influenza viruses can be grouped into two broad categories—A and B—which, in turn, split into subtypes. For the current season, influenza A viruses, including H1N1 and H3N2, have prevailed in flu cases across the country. Although flu shots have conferred robust protection against H1N1, against H3N2, it has been moderately lower. In areas where H3N2 is more concentrated, according to studies, flu shots have less frequently prevented cases among pediatric outpatients.

Laboratory testing research on ferrets, the typical animal model used for influenza research, has shown that the flu vaccine this year is not quite as good a fit for the spreading H3N2 viruses as it is for H1N1. Even so, general flu vaccine effectiveness is in line with previous flu seasons, and public health authorities continue to recommend widespread immunization.

Changes in Flu Shot Formulation- What's Different This Year?

For the first time since 2012, the U.S. flu vaccine has changed from a quadrivalent (four-component) to a trivalent (three-component) formula. This year's vaccine protects against two influenza A subtypes—H1N1 and H3N2—and one influenza B strain called the Victoria lineage. The fourth component from last year, the Yamagata lineage of influenza B, has been dropped, since international data show it might have become extinct.

Is It Too Late to Get Vaccinated for Flu?

Although the best time to get vaccinated is early fall before flu cases start to peak, it's never too late to get the flu shot. The CDC advises annual flu vaccination for all individuals above six months of age, and since flu cases can persist until May, getting vaccinated even later in the season can be of great benefit.

For those who still need to get their flu vaccination, infectious disease specialists say immunization is still important, especially for vulnerable populations, including:

• Pregnant women
• Elderly patients aged 65 and above
• People with pre-existing chronic health conditions
• Young children aged less than five years

Although the number of cases of flu might start decreasing towards spring, getting vaccinated can keep severe complications low and curtail the virus transmission.

In spite of the effectiveness of this season's flu shot, the next year's vaccine hangs in uncertainty. Generally, an FDA advisory panel gathers in early spring to choose strains for the upcoming year's vaccine. But this year, the meeting that was planned was abruptly canceled, leaving public health experts anxious.

Manufacturing of flu vaccine takes months because the chosen virus strains have to be grown in chicken eggs prior to mass production. Delaying strain selection will affect supplies of vaccines for the 2025-2026 season, which could translate to higher rates of severe illness and hospitalization.

In spite of these obstacles, the World Health Organization (WHO) has persevered with its yearly flu strain selection process, and only time will tell if the FDA will proceed on their own with strain selection in time for manufacturers to achieve the production timeline necessary.

Why Flu Vaccination Remains Essential?

Influenza is a potentially serious disease that can result in hospitalization and even death, especially in high-risk populations. Although some flu seasons are less severe than others, flu vaccines are essential in preventing complications, curbing the transmission of the virus, and reducing the burden on healthcare systems.

With the 2024-2025 flu season demonstrating promising vaccine efficacy, public health officials continue to emphasize the need for universal immunization. With flu cases continuing across various regions, vaccination remains the best method in preventing yourself and your loved ones from getting sick.

The 2024-2025 flu season has shown the power of this year's vaccine to prevent severe illness and hospitalizations. While there are regional differences, especially from the H3N2 strain, overall vaccine effectiveness is strong, matching some of the most protective flu seasons in the last 15 years. With flu season still present, health professionals recommend that individuals who have not yet been vaccinated get vaccinated as soon as possible.