Anaphylaxis after vaccines is a well known side effect, but just how common is it?
Anaphylaxis After Vaccines
Since it is listed as a possible reaction to nearly all vaccines and it can be life-threatening, anaphylaxis must be fairly common, right?
“Vaccine providers should be familiar with identifying immediate-type allergic reactions, including anaphylaxis, and be competent in treating these events at the time of vaccine administration. Providers should also have a plan in place to contact emergency medical services immediately in the event of a severe acute vaccine reaction.”
Preventing and Managing Adverse Reactions
After all, pediatricians even get warned to have a plan in place and to be prepared to treat children just in case they develop anaphylaxis after getting their vaccines.

Still, most probably have never had to.
“Any medication can cause a severe allergic reaction. Such reactions to a vaccine are estimated at about 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination.”
Possible Side-effects from Vaccines
And that’s because anaphylaxis after vaccines is very rare.
Anaphylaxis After Vaccines is Rarely Fatal
And suprisingly, it is even more rare for these cases to be fatal!
“All 30 patients with anaphylaxis survived (9 reports specified anaphylaxis, and we classified another 21 as probable cases, based on compatible clinical features, including respiratory and skin symptoms within 4 hours after vaccination). In half of 22 detailed reports, symptoms developed within 15 minutes after vaccination.”
Wise et al on Postlicensure Safety Surveillance for Varicella Vaccine
But that study just looked at the chicken pox vaccine and used VAERS, so we have to be concerned about under-reporting, right? Well, not necessarily. Under-reporting likely isn’t a big problem for serious reactions.
Anyway, that’s not the only study…
“We identified 33 confirmed vaccine-triggered anaphylaxis cases that occurred after 25,173,965 vaccine doses. The rate of anaphylaxis was 1.31 (95% CI, 0.90-1.84) per million vaccine doses.”
McNeill et al on Risk of anaphylaxis after vaccination in children and adults
The McNeill study used the Vaccine Safety Datalink, which unlike VAERS, is not a passive reporting system. So there is no concern about underreporting.
And like the Wise study, there were no deaths among these vaccine-triggered anaphylaxis cases.
“Fatalities from vaccine-induced anaphylaxis are exceedingly rare.”
Adverse reactions to vaccines practice parameter 2012 update
Similarly, a study in the UK found rare reports of anaphylaxis after vaccines in children and all those children made a full recovery.
Parents should understand that while anaphylaxis is a known side effect to getting a vaccine, it is extremely rare, and can usually be treated. This once again reinforces that vaccines are safe!
More on Anaphylaxis After Vaccines
- Vaccines Statistics and Numbers
- Vaccine Education for Pediatric Offices
- Are There Hidden Ingredients in Vaccines?
- Latex Allergies and Vaccines
- Neomycin in Vaccines
- Adjuvant 65 in Vaccines and the Peanut Allergy Epidemic
- What is the risk of anaphylaxis after vaccination in children and adults?
- WHO – Vaccine Anaphylaxis Information
- Adverse reactions to vaccines practice parameter 2012 update
- Study – Risk of anaphylaxis after vaccination in children and adults
- ACIP – Preventing and Managing Adverse Reactions
- CDC – Possible Side-effects from Vaccines
- Study – Postlicensure safety surveillance for varicella vaccine
- Study – Anaphylaxis as an adverse event following
immunisation in the UK and Ireland - Medical Management of Vaccine Reactions in Adult Patients
- Medical Management of Vaccine Reactions in Children and Teens
- Afraid of an Allergic Reaction to Vaccines? Chances are One in a Million