Considerations for causality assessment of neurological and neuropsychiatric complications of SARS-CoV-2 vaccines, 2021, Butler at al

Full title: Considerations for causality assessment of neurological and neuropsychiatric complications of SARS-CoV-2 vaccines: from cerebral venous sinus thrombosis to functional neurological disorder

Introduction

The scientific community rapidly responded to the COVID-19 pandemic by developing novel SARS-CoV-2 vaccines (table 1). As of early June 2021, an estimated 2 billion doses have been administered worldwide.1 Neurological adverse events following immunisation (AEFI), such as cerebral venous sinus thrombosis and demyelinating episodes, have been reported. In some countries, these have led to the temporary halting of both vaccine trials and roll-out programmes. In the absence of clear evidence of causal associations between the vaccine and adverse events, or the rarity of the AEFIs themselves, programmes have thus far been restarted, although sometimes with modifications to recommendations.2

Transient influenza-like symptoms such as headache, myalgia and fatigue have been reported in up to 5% of SARS-CoV-2 vaccine recipients in clinical trials,3 4 although these symptoms often indicate an appropriate immune response to vaccination.5 More severe potential adverse effects in the open-label phase of vaccine roll-outs are being collected through national surveillance systems. In the USA, roughly 372 adverse events have been reported per million doses, which is a lower rate than expected based on the clinical trials.6

Open access, https://jnnp.bmj.com/content/early/2021/08/05/jnnp-2021-326924

 

That seems expected. In trials they actively ask, while in normal health care settings there are multiple barriers preventing this from happening, can't find in data what never gets recorded.