JUNEAU, Alaska (AP) — Health officials in Alaska reported a health care worker had a severe allergic reaction to a COVID-19 vaccine within 10 minutes of receiving a shot.

U.S. health authorities warned doctors to be on the lookout for rare allergic reactions when they rolled out the first vaccine, made by Pfizer and Germany’s BioNTech. Britain had reported a few similar allergic reactions a week earlier.

The Juneau health worker began feeling flushed and short of breath on Tuesday, says Dr. Lindy Jones, the emergency room medical director at Bartlett Regional Hospital. She was treated with epinephrine and other medicines for what officials ultimately determined was anaphylaxis, a severe allergic reaction. She was kept overnight but has recovered.

Unlike the British cases, the Alaska woman has no history of allergic reactions.