A study conducted by researchers at the Global Vaccine Data Network (GVDN) in New Zealand examined 99 million individuals who were immunized against COVID-19 in eight different countries.
There were 99,068,901 vaccinated participants. Throughout the course of the trial, 183,559,462 doses of BNT162b2, 36,178,442 doses of mRNA-1273, and 23,093,399 doses of the ChAdOx1 (adenovirus vector) were given to participating sites. In follow-up, risk periods after homologous immunization schedules contributed 23,168,335 person-years. Following the first dose of the ChAdOx1 vaccine, observed vs. anticipated (OE) ratios with a lower bound of the 95% confidence level (LBCI) > 1.5 were noted for cerebral venous sinus thrombosis (3.23, 95% CI: 2.51, 4.09) and Guillain-Barré syndrome (2.49, 95% CI: 2.15, 2.87). After receiving the first dose of the mRNA-1273 vaccine, acute disseminated encephalomyelitis displayed an OE ratio of 3.78 (95% confidence interval: 1.52, 7.78). With LBCIs > 1.5, the OE ratios for myocarditis and pericarditis after BNT162b2, mRNA-1273, and ChAdOx1 were considerably elevated.
Link to the study: