(CNN) – A volunteer in AstraZeneca’s COVID-19 vaccine trial has died in Brazil, but the trial will continue.
The announcement comes from Anvisa, Brazil’s health agency.
It wasn’t clear whether the volunteer received the vaccine or a placebo shot. About a third of the people in the U.S. version of the trial are injected with a saline placebo.
AstraZeneca’s vaccine, developed with Britain’s Oxford University, is being tested in tens of thousands of volunteers around the world.
“We cannot comment on individual cases in an ongoing trial of the Oxford vaccine as we adhere strictly to medical confidentiality and clinical trial regulations, but we can confirm that all required review processes have been followed,” a statement from the drugmaker said.
Vaccine experts say volunteers in clinical trials can become ill or die for any number of reasons, and they may not be related to the vaccine.