The Italian Medicines Agency has published the third Pharmacovigilance Report on COVID-19 vaccines. The data collected and analyzed concern the reports of suspected adverse reactions registered in the National Pharmacovigilance Network between 27 December 2020 and 26 March 2021 for the three vaccines in use in the current vaccination campaign.
In the period considered, 46.237 reports were received out of a total of 9.068.349 doses administered (reporting rate of 510 per 100.000 doses), of which 92,7% referred to non-serious events, which completely resolve, such as pain on site. of injection, fever, asthenia / fatigue, muscle aches.
Serious reports correspond to 7,1% of the total, with a rate of 36 serious events per 100.000 doses administered, regardless of the type of vaccine, the dose (first or second) and the possible causal role of the vaccination.
Most of the reports are related to the Comirnaty vaccine (81%), so far the most used in the vaccination campaign (68% of the doses administered), with an increase in reports for the Vaxzevria vaccine (17%) following the increase in use of this vaccine (27% of administered doses). The reports relating to the Moderna vaccine instead represent 2% of the total and are proportional to the more limited number of doses administered (5%).
The reported events mostly occur on the same day of vaccination or the day after (87% of cases).
For all vaccines, the most reported adverse events are fever, headache, muscle / joint pain, injection site pain, chills and nausea, in line with known information on vaccines used in Italy so far.
A focus is dedicated to thromboembolic events after administration of Vaxzevria. Very rare cases of thrombi associated with low levels of platelets in the blood have occurred within 2 weeks of vaccination. Out of a total of 62 cases entered into Eudravigilance in Italy, 7 cases (with two deaths) of intracranial venous sinus thrombosis (CSVT) were reported up to 22 March 2021 and 4 cases (with two deaths) of thrombosis of several blood vessels in atypical office out of the 24 included in the European surveillance network in the same period. The investigation at national level of these reports is conducted with the support of a “Working Group for the evaluation of thrombotic risks from anti-COVID-19 vaccines”, made up of some of the leading national experts in thrombosis and haemostasis.
Adverse events not known are subject to continuous investigation at national and European level.