Every strain in this year’s flu vaccine differs from what practices stocked last fall. The FDA’s Vaccines and Related Biological Products Advisory Committee (VRBPAC) met in March and recommended updates to all three vaccine components, the first full reset in several years. For practices finalizing fall orders, that shift is worth considering now, both for what changed and why.
What This Means for Fall Ordering
For practices, this translates to several practical steps rather than a single change. The vaccine remains trivalent, meaning it targets three flu strains, rather than quadrivalent, which targets four. That’s been the case since the 2024–25 season. Nothing changes about the number of components in this year’s vaccine, only the viruses those components target.
Practices should confirm directly with each manufacturer that fall shipments reflect the updated formulation, rather than assume an order will simply carry over from last season. This is particularly important for practices using more than one brand or production type, since egg-based, cell-based, and recombinant vaccines may not complete reformulation and release on the same timeline.
That timeline is also a reason to order early. Manufacturers need time to reformulate, produce, and release each updated vaccine, and any slowdown along the way is more likely to result in a delayed shipment than a canceled order. Placing orders early and asking about anticipated shipping windows gives practices more flexibility if a particular product falls behind schedule.
Ordering season is also a convenient time to look beyond flu. Many patients who come in for a flu vaccine may also be due for an updated COVID-19 vaccine or, if eligible, an RSV vaccine. A single visit is often the easiest opportunity to provide all recommended vaccines.
Timing Still Matters Most
The CDC recommends flu vaccination for everyone age six months and older, ideally by the end of October. However, vaccination later in the season can still provide meaningful protection, as flu activity typically continues into the spring. Being prepared for that window depends on having vaccine available, placing the ordering timeline on equal footing with the clinical timeline.
A Full Reset, Not a Single Swap
That preparation depends on understanding what actually changed in this year's vaccine. Each flu vaccine is built around three components: two influenza A subtypes and one influenza B strain. Most years, the FDA updates one of those components, perhaps two. This year it updated all three, the first full reset in several years, affecting egg-based, cell-based, and recombinant vaccines alike.
Much of the update centers on an influenza A subtype. A new version of the virus, known as subclade K, emerged after last season’s strains had already been selected and went on to become the dominant circulating strain by season’s end. This year’s formulation was chosen specifically to close that gap.
Why It’s Worth Practices’ Attention
Subclade K circulated widely and hit older adults— already at elevated risk for severe flu—especially hard, with CDC surveillance showing adult hospitalization rates at their third-highest level in over a decade. Most pediatric flu deaths with a known vaccination history occurred in patients who hadn’t completed a full vaccination course. The takeaway for practices: a vaccine built around the strains actually driving illness offers stronger protection through the full season.
None of that changes what matters most for fall ordering: confirming the current formulation with each manufacturer and placing orders early. Atlantic Health Partners works directly with the full range of flu vaccine manufacturers, across egg-based, cell-based, and recombinant formulations. We help practices secure favorable pricing and plan orders around each manufacturer’s production and shipping schedule. That support makes the ordering side of flu season one less thing for a practice to manage alone. Reach out to learn more.