Risk for Bell Palsy Up 42 Days After First Dose of CoronaVac
Hong Kong study shows small increased risk after Sinovac Biotech vaccine, but no significantly increased risk after BNT162b2 vaccine
WEDNESDAY, Aug. 25, 2021 (HealthDay News) -- The risk for Bell palsy is increased after CoronaVac vaccination, but not after BNT162b2 vaccination, according to research published online Aug. 16 in The Lancet Infectious Diseases.
Eric Yuk Fai Wan, Ph.D., from the University of Hong Kong, and colleagues examined the risk for Bell palsy within 42 days following vaccination with BNT162b2 (Fosun-BioNTech [equivalent to Pfizer-BioNTech]) or CoronaVac (from Sinovac Biotech, Hong Kong). Cases of Bell palsy were described among vaccine recipients; the estimated age-standardized incidence of clinically confirmed cases among individuals who had received the CoronaVac or BNT162b2 vaccination (451,939 and 537,205 individuals who received the first dose, respectively) was compared to the background incidence in the population.
The researchers identified 28 and 16 clinically confirmed cases of Bell palsy following CoronaVac and BNT162b2 vaccination, respectively, with an age-standardized incidence of 66.9 and 42.8 per 100,000 person-years, respectively. Compared with the background incidence in the population, the age-standardized difference for the incidence was 41.5 and 17.0 for CoronaVac and BNT162b2, respectively, equivalent to an additional 4.8 and 2.0 cases per 100,000 people vaccinated, respectively. The adjusted odds ratios were 2.385 (95 percent confidence interval, 1.415 to 4.022) and 1.755 (95 percent confidence interval, 0.886 to 3.477) for CoronaVac and BNT162b2, respectively, in the nested case-control analysis with 298 cases matched to 1,181 controls.
"Our study shows an overall increased risk of Bell's palsy after CoronaVac vaccination but not after BNT162b2 vaccination," the authors write. "The beneficial and protective effects of the inactivated COVID-19 vaccine far outweigh the risk of this generally self-limiting adverse event."
Several authors disclosed ties to the biopharmaceutical industry.