Covid-19 Vaccination Advantages of Opting for an Active Pharmacovigilance Model

Abstract

Background: To measure vaccination`s risks it exists the term “events supposedly attributed to vaccination or immunization”(ESAVI). ESAVI monitoring usually consist in passive surveillance based on voluntary notifications done either by beneficiariesor by health professionals. The spontaneous reports are scarce compared with active surveillance. Unfortunately; activemethods performed by health service are expensive, laborious and unfeasible due to the few health personnel available.Objective: to evaluate the efficacy of an active method for ESAVI reports associated to COVID19- vaccines performed byuniversity students.Methods: a research comparing two Pharmacovigilance methods for COVID-19-ESAVI was performed (passive vs activesurveillance with participation of university students) from May to September 2021.Results: At the end of the study period, in Argentina 52.786.324 anti-COVID-19 vaccines were applied (1st dose 56, 86%; 2nddose 43, 14%), and 102.358 ESAVIs were validated (1st dose 74, 75%; 2nd dose 23, 96%; other dose 0, 5%; No data 1, 24); 2,16% among them were considered severe. Although female/male vaccination/ratio was similar (50.31% vs 49.67%), ESAVIwere much more reported by females (72.8%). The active pharmacovigilance experience was performed by 933 students-volunteers. They contacted 56,824 vaccinated people; obtaining 39,952 “positive” calls (either “no events” or “potential ESAVI”results). The monthly contacts performed by students were 14,206±1124; among them, 1186±436 calls were “refused”, whilein 3,032±741 cases existed wrong phone number. From 6.652 potential ESAVI reported; 1,037 were validated, which means1.82% of vaccinated people contacted, certainly a better result than the 0.121%obtained by passive reports (p <0.0001).Conclusion: An active method of pharmacovigilance performed by health students was able to increase 15 times the validatedESAVI reports after COVID-19 vaccination.