A health care worker at the Bartlett Regional Hospital in Juneau, Alaska, developed a severe allergic reaction shortly after receiving the Pfizer Covid-19 vaccine Tuesday evening, and had to be hospitalized overnight.
During a media briefing Wednesday, health officials said the middle-aged woman had no history of allergies and had never experienced anaphylaxis, a severe and life-threatening allergic reaction.
Bartlett Regional Hospital officials said all 96 of its workers who received the vaccine Tuesday were observed for 30 minutes after the shot. The woman starting feeling flushed about 10 minutes into that observation period, and took Benadryl, an antihistamine.
However, her symptoms progressed to an elevated heart rate and shortness of breath, and was sent to the hospital's emergency department.
"She had a red, flushed rash over her face and torso," Dr. Lindy Jones, the emergency physician who treated her, said during the briefing Wednesday. "I was concerned about an anaphylactic reaction." Jones gave her an emergency injection of epinephrine.
Her symptoms abated for a short time, but then re-emerged. She was put on intravenous epinephrine, and moved to the hospital's intensive care unit where she remained overnight. Jones said the woman did not necessarily require ICU resources, but added, "we are a small little hospital here, so if we are concerned about anyone, we put them in the ICU."
As of Wednesday morning, the woman was off all medications, and was expected to be discharged Wednesday evening.
Pfizer said in a statement that the company is "working with local health authorities to assess" the reaction that occurred in Alaska, and will "closely monitor all reports suggestive of serious allergic reactions following vaccination and update labeling language if needed."
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That hospital officials were able to identify the reaction and treat it appropriately "demonstrates that the vaccine safety monitoring system is strong and robust for handling the pandemic response," Dr. Jay Butler, head of the Covid-19 response at the Centers for Disease Control and Prevention, said.
Butler said the Alaska case is the only allergic reaction to the Pfizer-BioNTech vaccine reported in the United States so far.
Two health care workers in the United Kingdom experienced similar allergic reactions after receiving the Pfizer vaccine last week. After the Food and Drug Administration authorized the vaccine for emergency use in the U.S., the regulatory agency said people with a history of allergic reactions should speak with their doctors about the vaccine, but added there was not enough evidence to suggest the majority of people with allergies steer clear of the shots.
Allergic reactions to vaccines or other medications are rare, but do occur. Any facility qualified to administer vaccines is equipped with emergency epinephrine (known to many as an EpiPen) in the event of severe reactions.
Despite her reaction and subsequent hospitalization, health officials said, the health care worker "was enthusiastic that she got the vaccine," specifically about the benefits it might eventually offer her.
Still, Butler said the woman will be advised to skip the second dose.