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COVID-19 vaccine rollout: Adverse events being watched but no one has needed hospitalization

One death of an elderly resident in Windsor is being investigated

The Ontario Ministry of Health told reporters Tuesday there have been some adverse events with COVID-19 vaccines, but nothing that has resulted in any hospitalizations of the vaccine recipients.

The information was provided at a mid-morning technical briefing at Queen's Park to provide background information on the proviso that none of the high-level Ministry of Health officials taking part would be identified. 

There was a question of whether any adverse events were being measured, especially for vulnerable and elderly residents who are receiving vaccines such as the Pfizer BioNtech and Moderna vaccines.

A ministry official responded that the monitoring of adverse events following immunizations is a key part of the program.

"Certainly with these, given they're relatively new vaccines, there is a mechanism and a requirement that any adverse event be reported to the local health department and then investigated through Public Health Ontario and up to the federal level."

At that level, said the ministry official, there is a committee that would look at the adverse event to determine whether the reaction was indeed the result of a vaccine or whether it was a coincidence to another condition.

"What we have found so far is we have very few reports of serious events, and they're mostly allergic. They have not required hospitalizations," said the official. 

She added that in most cases among vaccine recipients the most common complaint is having a sore arm.

"Some people will get a fever and muscle aches and feel kind of lousy for a day or two," she added. 

In general, she said the experience so far is that the COVID-19 vaccines have been safe.

Another reporter suggested that since the vaccine types are new, wouldn't it be more prudent to test out of the vaccines on a larger population of younger and more healthy citizens first since they might be less susceptible to any adverse event that might arise from what is still an “experimental vaccine.”

The ministry official, herself a physician, responded quickly.

"These are definitely not experimental vaccines," she said. "The vaccines have gone through all the usual rigours that any vaccine has to go through for Health Canada approval. They were tested on many, many thousands of people. Off the top of my head, I believe 40,000 for the Pfizer and something similar for the Moderna.”

She added the vaccine pre-testing involved thousands of people of different ages.

"Yes they were approved quickly because it is an emergency situation. We have people who are getting very ill, people who are dying. We are in the middle of a pandemic of a very serious illness," she said.

Another question at the briefing asked about the details of a recent death of a Windsor-area resident, who was reported to have died after receiving one of the COVID-19 vaccines. The Windsor Essex County Health Unit (WECHU) has confirmed the death and said all factors, including the health history of the deceased person, would be taken into account. 

Officials were asked about the death and whether it would change Ontario's vaccine program rollout.  

"I can confirm that we are investigating and we are working with the public health unit, and to try to understand the circumstances of the death," said a ministry official. 

The official said the investigation was in the early stages to see if the vaccine had any relationship with the cause of death.

Len Gillis is a Local Journalism Initiative reporter at, covering health care in Northern Ontario. The Local Journalism Initiative is funded by the federal government. 

About the Author: Len Gillis, local journalism initiative reporter

Len Gillis is a Local Journalism Initiative reporter at covering health care in northeastern Ontario and the COVID-19 pandemic.
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