ABSTRACT
Background: Public concern has risen regarding the risk of hypersensitivity reactions (HSR) due to vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV- 2) in the general allergic population, especially in those with a history of anaphylaxis. Moreover, the associated alarm that patients diagnosed with allergies to polyethylene glycol (PEG) could suffer from an allergic reaction to vaccines against SARS-CoV- 2 has become a limitation during the mass immunization campaign. Method(s): Objective: 1. To describe the management implemented between allergology and primary care physicians (PCP) in our territory during the first mass immunization campaign in order to safely reach the largest number of people immunized. 2. To only asses patients at risk of having an HSR to the components of the SARS-CoV- 2 vaccine according to the algorithm implemented in primary care centers. Method(s): A retrospective study was performed including patients referred to the allergist by PCP due to the potential risk of presenting HSR to SARS-COV- 2 vaccines between March and September 2021. An algorithm was created, to assess the potential risk of presenting HSR to SARS-COV- 2 vaccine in allergic population. Patients were visited firstly by PCP, who applied the algorithm proceeding with virtual consultation with the allergist if needed. Risk assessment performed by the allergist determined if vaccination could continue at their assigned place or if an allergological diagnosis approach was needed. The rate of virtual and physical consultations with the allergist as well as the results of skin test and drug provocation tests were recorded. Result(s): A total of 181 patients were assessed virtually. A total of 147 (81%) patients were immunized at their assigned vaccination point after virtual consultation without incidences. On the other hand, 19% of the patients were assessed by the allergist physically and only 12 (6.6%) patients underwent skin tests and drug provocation test with negative results and good tolerance to the vaccine in all cases. Conclusion(s): A careful allergological risk assessment protocol significantly reduced the number of patients who would have avoided vaccination due to a history of allergies or apparent HSR to the first doses of SARS-CoV- 2, demonstrating the low incidence of true allergy to SARS-COV- 2 vaccines in our territory.