Coronavirus

Brazil ask vaccine labs to warn about possible side-effect syndromes

Brazil ask vaccine labs to warn about possible side-effect syndromes
Photo: Luchschen F/Shutterstock

Brazil’s federal health regulator Anvisa plans to ask major vaccine producers to inform about the possible risks of Guillain-Barré syndrome, which is among the rarest side effects of coronavirus vaccination. 

According to Anvisa, at least 34 cases of the syndrome have been detected as of today — 27 related to AstraZeneca, four to CoronaVac, and three to single-shot Janssen vaccines. Guillain-Barré syndrome is a rare autoimmune neurological disorder which can cause the immune system to attack nerve cells. 

However, cases associated with the vaccines administered in Brazil are “rare,” said the regulators, adding that they only want to certify that the information is properly labeled.