The UK drug regulatory agency MHRA is specifying its warning about the Pfizer / BioNTech vaccine for people with a significant allergic history.

“Individuals with a history of anaphylactic shock from vaccines, drugs, or food should not receive the Pfizer / BioNTech vaccine.
The second dose should not be given to anyone who has developed anaphylaxis after receiving the first dose of this vaccine," stated June Raine, managing director of the MHRA on Thursday.

The warning came after two cases of severe allergic reactions occurred with the UK's first anti-Wuhan virus vaccinations.