WASHINGTON (NEWSnet/AP) — An FDA panel has recommended that this fall’s COVID-19 vaccines target a version of the coronavirus referred to as JN.1.

While the total number of COVID-19 cases currently is low, manufacturers need time to create enough doses for what has become an annual fall vaccination campaign.

Moderna, Pfizer and Novavax all have tested doses updated to match the JN.1 variant that became dominant last winter. Since that time, some offshoots of JN.1 have been detected, prompting Moderna and Pfizer to also test a slightly different vaccine formula targeting what’s now the most common U.S. subtype, called KP.2.

The circulating variations are making a difficult choice for the Food and Drug Administration, as it decides on a formula for the next doses.

FDA’s advisers voted Wednesday that the next vaccine should come from the JN.1 “lineage” or family. Then FDA vaccine chief Dr. Peter Marks challenged them to be more specific about exactly which variant to target, wondering if KP.2 was a better option.

“If this evolves further in the fall, will we regret not having been a little bit closer?” Marks said, likening the choice to how he always picks the “freshest” milk with the longest expiration date in the grocery store.

But KP.2 isn't likely to still be the biggest threat by fall, the panel responded.

Health officials have told Americans to expect a yearly update to COVID-19 vaccines, just like they get a new flu shot each fall designed to match as best as possible the currently spreading strains.

Even though many people either have been infected or had at least one round of COVID-19 vaccinations, the coronavirus keeps churning out new varieties that can evade prior immunity -– and protection also wanes over time.

As in previous years, the CDC will make recommendations on who should receive updated shots and when.

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