A health care worker in Alaska has shown a serious allergic reaction to the coronavirus vaccine developed by U.S. pharmaceutical giant Pfizer Inc. and its German partner BioNTech SE, local authorities said Wednesday.

It was the first confirmed report of an adverse reaction to the COVID-19 vaccine in the United States, which began administering it on Monday. Similar allergic reactions by two health care workers have been reported in Britain after it became the first nation to roll out the Pfizer-BioNTech vaccine earlier this month.

Pfizer headquarters in New York City. (Kyodo)

The health care worker in Alaska, who has no history of allergies, suffered an anaphylactic reaction that included flushing and shortness of breath 10 minutes after receiving the vaccine on Tuesday, the state government said.

The worker was identified as a middle-aged woman in a New York Times report that cited a hospital official. The allergic symptoms were discovered during the 15-minute observation period recommended by the Centers for Disease Control and Prevention, the nation's health protection agency, according to the state government.

After being admitted to an emergency department, the patient was in stable condition but is still being monitored in hospital, it added.

"We expected that a side effect like this could occur after reports of anaphylaxis were made in England after people there received the Pfizer-BioNTech COVID-19 vaccine," said Anne Zink, Alaska's chief medical officer.

Supplied electron micrograph shows the new pneumonia-causing coronavirus. (Photo courtesy of the U.S. National Institute of Allergy and Infectious Diseases)(Kyodo)

Britain, the first Western country to put a COVID-19 vaccine into general use, said Wednesday at least 137,897 people received initial shots in the first week of the rollout of the vaccine, which began Dec. 8. A second shot is required three weeks later to complete vaccination.

The two British health care workers who have developed allergic reactions to the vaccine had a history of anaphylaxis because of food and medicine allergies, prompting the local health authorities to warn those who have experienced similar reactions in the past not to receive the new vaccine.

As Europe has recently seen a resurgence in COVID-19 cases, Germany intends to start inoculating with the Pfizer-BioNTech vaccine on Dec. 27, according to news reports Wednesday quoting Health Minister Jens Spahn.

But as a member of the European Union, Berlin must wait for approval by the European Medicines Agency. Local media reported the agency is expected to give its final approval for the vaccine on Dec. 23.

Related coverage:

U.S. begins administering 1st doses of COVID-19 vaccine