OTTAWA - Concerns about vaccine safety emerged again Tuesday, as Canada reported its first case of vaccine-induced blood clots linked to Oxford-AstraZeneca, and the United States put the brakes on the Johnson & Johnson vaccine following six reports of blood clots there.

Officials in both countries, however, continued to stress the vaccines are safe, and their benefits outweigh their risks, even as investigations into what is causing the clots continue.

The vaccine news is also dropping as the third wave of COVID-19 is exploding. Canada now has one of the highest rates of new cases in the world, and a record number of patients in critical care.

The Quebec health ministry and Public Health Agency of Canada reported the Canadian blood clot in separate statements Tuesday afternoon. The woman, whose age was not specified, received the AstraZeneca vaccine made at the Serum Institute of India, known by the brand name Covishield.

“The person was taken care of by the health and social services network and received the care appropriate to their condition,” said Quebec's statement. “She is now recovering at her home and there is no fear for her life.”

Quebec said it has given out 185,000 doses of AstraZeneca so far, and this is the first and only blood clot report, making it an extremely rare event. Nationally, 700,000 doses had been given as of April 3 and no other reports of clots have been made in Canada to date.

Last week, Europe and the United Kingdom reported 222 cases of blood clots out of more than 34 million shots given.

Health Canada said with all the information it has, the benefits of the vaccine continue to outweigh its risks, particularly as the risk of a vaccine-induced clot is less than one in 100,000.

Blood specialists, infectious disease experts and the drug regulators say the risk of blood clots is vastly lower from the vaccines than from COVID-19 itself. The syndrome is treatable if caught.

Canada's chief public health officer, Dr. Theresa Tam, said there is a rigorous safety process to monitor for any serious adverse events following vaccination, and Canadians can trust the system.

Health Canada has added a warning about the potential risk of clots to the AstraZeneca label, and the National Advisory Committee on Immunization recommended that vaccine not be used on people under 55, because most reports thus far showed patients with blood clots were younger. Health Canada is also getting a risk analysis by age and gender from AstraZeneca that could inform future decisions about the vaccine's use.

In a tweet Tuesday, Health Canada said it was also aware the U.S. had paused the use of J&J's vaccine because of clots. The U.S. has six reports out of more than 6.8 million shots given. Health Canada has asked the drug maker for more information, and is in touch with U.S. officials as well.

Dr. Anthony Fauci, the head of the U.S. Institutes of Health and Infectious Diseases, said the U.S. pause is out of an abundance of caution, and a desire to quickly get to the bottom of what might be going on.

“You want to make sure that safety is the important issue here,” he said. “We are totally aware that this is a very rare event. We want to get this worked out as quickly as we possibly can.”

Canada has approved J&J but isn't expecting any deliveries until the last week of April.

Johnson & Johnson issued a written statement Tuesday saying they are working with U.S. authorities, and have also decided to pause the rollout of their vaccine in Europe for now, as investigations on the blood clots are completed.

“The safety and well-being of the people who use our products is our number one priority,” the company said.

As of Tuesday, 20 per cent of Canadians have now received at least one dose of vaccine, and the pace of vaccinations has continued to rise. More than 336,000 vaccines were given out Monday, a new one-day record.

Canada is now giving out vaccines at a rate of almost seven per 1,000 people a day, up from five just two weeks ago, and only 2.5 a month ago.

But Prime Minister Justin Trudeau said while “everyone is working around the clock” to get vaccines out as quickly as possible, the pandemic is still raging around us.

“The situation we're facing with COVID-19 remains extremely serious,” Trudeau said Tuesday.

There were 8,500 new COVID cases in Canada Monday, nearing the one-day record of 9,200 set in early January. And Tam said over the last seven days, there were an average of 970 people in intensive care with COVID-19, the highest number ever.

The previous seven-day average was 880 in mid-January.

Canada's new case rate is now well ahead of the United States, at 289 new cases for every million people compared to 212 in the U.S. The European average is 209.

Vaccines may be providing some welcome good news in keeping deaths down. Tam reported an average of 34 deaths per day in the last week, compared to 140 when ICU numbers were similar in January.

People the most at risk of dying have been vaccinated in high numbers, with more than 80 per cent Canadians over 80 now being immunized. Long-term care homes are similarly well covered by vaccines.

“We do believe the vaccine has had an impact, and has been effective in reducing severe outcomes,” said Tam.

This report by The Canadian Press was first published April 13, 2021.