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Epidemiology for public health - ISS

COVID-19 vaccine safety: the AIFA annual report

The “Annual COVID-19 vaccine safety report 27/12/2020 - 26/12/2021” is now available online. It provides an analysis of the 117,920 reports of suspected adverse reactions to COVID-19 vaccination submitted to the National Pharmacovigilance Network between 27 December 2020 and 26 December 2021. Considering that 108,530,987 doses were administered, the rate of reporting was 109 per 100,000 doses. The breakdown of reports by vaccine type was as follows: Comirnaty (the most commonly used vaccine, 68%), Vaxzevria (19.8%), Spikevax (10.8%) and Janssen COVID-19 vaccine (1.4%).

As for the severity of reactions:

  • 83.7% of the reports (98,717) were of non-serious adverse events (91 events/100,000 doses administered)
  • 16.2% of the reports (19,055) were of serious adverse events (17.6 events/100,000 doses administered).

For all vaccine types, the most frequently reported adverse events were: fever, fatigue, headache, muscle/joint pain, pain at the injection site, chills and nausea. Most of the events were non-serious and had resolved by the time of reporting.

The rate of reporting following third doses was lower than the rate observed after the first and second doses (21.7 reports per 100,000 doses administered).

Most of the reports submitted after heterologous vaccination involved the administration of an mRNA vaccine after an adenoviral vector vaccine, described non-serious events and were similar to the other reports.


Pregnancy, breastfeeding and fertility

Pharmacovigilance data and ad hoc studies of pregnant and breastfeeding women have not revealed specific safety concerns, and there is no evidence to suggest that COVID-19 vaccination may adversely affect fertility in either men or women.



Reporting rates for the 5-11 age group are preliminary, and no specific safety concerns have been identified.


The most frequently reported adverse events were fever, headache, fatigue and vomiting. Overall, 69% of the reactions observed among children had fully resolved or were resolving by the time of reporting.


Useful resources


Page published: 17 February 2022

Written by: Pharmacoepidemiology and Pharmacosurveillance Unit of the National Centre for Pre-Clinical and Clinical Drug Research and Evaluation.