A prominent physician and key member of Canada's COVID-19 Immunity Task Force says the World Health Organization (WHO) placed too much confidence in Chinese data on the outbreak and set back the world's response by as much as three weeks.

"I think they were a little too deferential. They knew from SARS-1 that there had been problems with incomplete reporting," Dr. David Naylor told CBC News Network's Power & Politics Thursday.

"I think we lost two to three weeks and I think that's regrettable, and I think that will come to light when a review is done."

Naylor, the former president of the University of Toronto and an inductee into the Canadian Medical Hall of Fame, has been named to a federal task force charged with overseeing the co-ordination of a national blood testing campaign to see how far the virus has spread and to estimate Canadians' immunity to the disease.

Other doctors on the task force include Dr. Catherine Hankins, Dr. Tim Evans, Dr. Theresa Tam and Dr. Mona Nemer.

Naylor told host Vassy Kapelos that while the WHO may have put too much trust in the data China released, the delay in getting information out did not result in the loss of "a huge amount of time" in the fight against the pandemic.

"I don't think this was a massive amount of time lost," he said. "People who say that it … completely changed the course of the outbreak are simply wrong."

Despite those missteps, Naylor said Canada should not re-examine its relationship with the WHO because it plays an important role in ensuring global co-ordination in a pandemic. Instead, Naylor said that such agencies need to be made better through scrutiny to ensure they can perform well.

"They are simply too important to not be held to high standards," he said, "but also to be supported and be a source of multilateral collaboration that protects us all. So, engage, scrutinize, hold accountable … and make better."

Long-term care failure

Looking at how governments in Canada have responded to the pandemic, Naylor said there have been a number of missteps but he is reluctant to "armchair quarterback" the crisis because, he says, there will be plenty of time for that later.

But he said he had no reservations pointing out the failure to protect vulnerable, elderly populations in long-term care facilities.

"I think that one thing that we missed out on was figuring out how to protect some of these vulnerable populations, that's a miss," Naylor said.

"Right now I think the area of acute focus for everybody has to be those homes. The long-term care facilities and the seniors, that's a big miss. And it has to be remedied quickly. It's unacceptable, as the prime minister said."

WATCH | Dr. Naylor's full interview with Power & Politics host Vassy Kapelos: