UK health authorities said Wednesday that people with “significant history of allergic reactions” should not take the Pfizer/BioNTech coronavirus vaccine, according to CNN.

  • The warning came after two health care workers suffered symptoms after receiving a shot on Tuesday.
  • The Telegraph reports the two National Health Services employees suffered “anaphylactoid reactions” to the vaccines.
  • The pair “responded adversely” to the COVID-19 vaccine after it was released in the UK.
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The staffers had a history of allergic reactions. Thousands of others received the first vaccine shot, though, and did not respond any problems, according to CNN.

  • “As is common with new vaccines the MHRA (Medicines and Healthcare products Regulatory Agency) have advised on a precautionary basis that people with a significant history of allergic reactions do not receive this vaccination after two people with a history of significant allergic reactions responded adversely yesterday,” said Stephen Powis, the national medical director for NHS England, in a statement. “Both are recovering well.”

Millions still plan to get the COVID-19 vaccine in the UK later this month, according to NPR.