Following requests received from some Regions regarding the measures to be taken following the appearance of a serious adverse reaction (ADR) after the first dose of an anti COVID-19 vaccine, AIFA, having heard the opinion of its Scientific-Technical Committee, specifies that it is not possible to provide general recommendations in light of the heterogeneity of the cases, which require specific clinical evaluation.

However, similarly to what has already been decided for subjects <60 years of age, by applying the principle of maximum precaution, the Agency specifies that a booster with an m-RNA vaccine can be performed in subjects who have experienced serious adverse reactions of the thrombotic type or in any case affecting coagulation after administration of Vaxzevria.

For other ADR cases, in the absence of data from ad hoc studies, it is seemingly not possible to make general recommendations regardless of the examination of specific ADRs and of the clinical evaluation of individual cases.