Listening to Twitter about Adverse Events of the Comirnaty COVID-19 Vaccine during first weeks of immunisation in Poland

Abstract

Aim. We perform an exploratory study of how Social Media Listening using simple keywords can be useful in pharmacosurveillance of Adverse Events (AE) of COVID-19 vaccines.Concept. 43375 Tweets about vaccines during the fi rst weeks of Comirnaty COVID-19 vaccine roll-outs in Poland were collected. We analyse the frequency of occurrence of selected common symptoms by infodemiological (related to self-reporting posts) and compare them with the epidemiological (product summary and post-registration) surveillance in Poland.Results. The AE keywords posting in Social Media is mainly driven by media interest rather than real burden of AE. The best accordance between infodemiological and epidemiological surveillance was found for systemic reactions, however local and gastric reactions seems to be underrepresented in social media. Conclusion. Infodemiology can be useful in early warning pharmacosurveillance of some AE during massive drug delivery as immunisation. Some keywords of symptoms such as fever or pain seem to be the most promising and due to low cost of monitoring should be incorporated in real-time dashboards for decision makers.