New Delhi: A volunteer participating in clinical trials of the COVID-19 vaccine developed by pharmaceutical firm AstraZeneca and Oxford University has died in Brazil, announced the Brazilian health agency Anvisa on Wednesday adding that the trial will continue. Also Read - India May Get 100 Million Doses of Oxford's Coronavirus Vaccine by January, Says Adar Poonawalla

According to reports, the volunteer was a 28-year-old doctor working on the frontlines of the pandemic, treating coronavirus patients since March in two hospitals in Rio de Janeiro and died of complications after contracting the virus. Also Read - Oxford-Astrazeneca Vaccine 90% Effective in Preventing COVID, Show Results

It is the first death reported in the various coronavirus vaccine trials taking place worldwide. Also Read - COVID-19: When Will India Get Vaccine? How Many Indians Will be Inoculated by Next Year? Health Minister Answers

Oxford confirmed the plan to keep testing, saying in a statement that after careful assessment “there have been no concerns about safety of the clinical trial.”

Brazilian newspaper Globo and international news agency Bloomberg said he was in the control group and had received a placebo rather than the test vaccine, citing sources close to the trials.

AstraZeneca said medical confidentiality meant it could not give details on any individual volunteer, but that independent review had “not led to any concerns about continuation of the ongoing study.”

Oxford and AstraZeneca previously had to suspend testing of the vaccine in September when a volunteer in Britain developed an unexplained illness.

Trials resumed after British regulators and an independent review concluded the illness was not a side effect of the vaccine.

Half the volunteers in the final-stage clinical trial — a double-blind, randomized, controlled study — receive a placebo, IDOR said.

Around 8,000 volunteers have been vaccinated so far in Brazil, and more than 20,000 worldwide, it said.

Study participants must be doctors, nurses or other health sector workers who come into regular contact with the virus.