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Anaphylaxis is 'extremely rare', says study

Anaphylactic shock following vaccination is “extremely rare”, a study has found.

Research published in the Archives of Disease in Childhood shows less than half of anaphylaxis cases studied were confirmed as true allergic reactions.

The study analysed under-16s in the UK and Ireland, who were suspected by specialists of having experienced anaphylaxis after being vaccinated between 2008 and 2009.

It was found that only seven of the fifteen cases reported were confirmed as true anaphylaxis.

As two of the cases were associated with the single component measles vaccine, researchers said around 12 anaphylaxis cases are likely to occur for every 100,000 doses.

Similarly, as three cases were associated with the HPV vaccine, the researchers expect 1.4 anaphylaxis cases to occur in every million doses.

None of the anaphylaxis cases studied were found to be associated with the normal pre-school or infant immunisation schedule, including the triple MMR jab.

Researchers conclude almost 5.5 million children would have received routine vaccinations during this period without any reported cases of anaphylaxis.

“This is extremely reassuring data for the general public and healthcare workers alike,” said the researchers.

“Despite its limitations, the small numbers of cases reported are likely to be a true estimate of anaphylaxis [following immunisation] rates.”

Question: Does the study's findings reflect your experiences?