The beneficial effects of COVID-19 vaccines far outweigh the danger of facial paralysis on one side of the face referred to as Bell’s Palsy, confirms a large-scale population-based study published within the Lancet Infectious Diseases journal The researchers from The University of Hong Kong found that for each 100,000 people vaccinated with inactivated vaccine, CoronaVac, a further 4.8 people may develop the condition.

Bell’s palsy is that the sudden onset of one-sided facial paralysis. within the majority of cases, the condition resolves itself within six months without treatment and therefore the chance of recovery is even higher if patients receive early treatment with corticosteroids, they said Our study suggests alittle increased risk of Bell’s palsy related to CoronaVac vaccination,” said study lead author Professor Ian Chi Kei Wong from The University of Hong Kong .
“Nevertheless, Bell’s palsy remains a rare, mostly temporary, adverse event. All evidence so far , from multiple studies, shows that the beneficial and protective effects of the inactivated COVID-19 vaccine far outweigh any risks,” Wong said.
A small number of cases of Bell’s palsy are reported in clinical trials of mRNA COVID-19 vaccines, but thus far , analyses of the association have come to conflicting conclusions In the US, the Federal Drug Administration (FDA) didn’t consider there to be a transparent causal association for the 2 mRNA vaccines by Pfizer-BioNTech and Moderna but recommends ongoing surveillance.

However, acute partial facial paralysis is reported as a rare side effect of both the vaccines by the ecu Medicines Agency Current prescribing information for CoronaVac doesn’t list Bell’s palsy as a rare adverse event.
However, supported the findings from the study, approval has been obtained to incorporate information on the potential association, the researchers said.

The study analysed cases of Bell’s palsy associated with the 2 approved vaccines in Hong Kong — CoronaVac and BNT162b2 The study used data from the Hong Kong drug regulatory agency pharmacovigilance system, which incorporates reports of adverse events logged by health professionals throughout the territory Cases of Bell’s palsy were included within the analysis if they occurred within 42 days of the primary or second vaccine dose, within the timeframe of the study.

Between February 23, 2021 and should 4, 2021, 28 clinically confirmed cases of Bell’s palsy were identified among the 451,939 individuals who received a minimum of one dose of CoronaVac and 16 cases were identified among the 537,205 individuals who received a minimum of a primary dose of BNT162b2.

By analysing data from 2010-2020, the researchers estimated the background risk of Bell’s palsy in Hong Kong — around 27 cases per 100,000 people, per year Global estimates range from 15-30 cases per 100,000 people, per year, consistent with the researchers.

The study found that receiving CoronaVac was related to 2.4 times increased risk of Bell’s palsy whereas receiving BNT162b2 wasn’t related to a significantly increased risk The researchers concluded that for each 100,000 people vaccinated with CoronaVac, a further 4.8 people may develop Bell’s palsy For BNT162b2, the increased risk was like a further 2 cases per 100,000 people vaccinated, they said.

Further studies with a sufficient sample size are needed to guage the association between Bell’s palsy and BNT162b2.
The authors noted that they can’t conclude a causal relationship between Bell’s palsy and vaccination in a person cases from this study, which the mechanism by which vaccination can — in very rare instances –lead to Bell’s palsy remains unclear.