(Photo: Canadian Press)

When Craig Sylvant stood in line to get a COVID-19 vaccine, he was aware that the dose injected into his arm could leave him with side effects.

The 46-year-old cultural columnist recounts how he inflicted a mythical hangover upon himself during his lifetime.

So the possibility of “vaccine residues” occurring in exchange for a dose that would protect him and his family was an easy choice. He laughs, he said, that he liked to believe that “all the extra alcohol” he had made in his life helped him prepare for the unwanted side effects of the vaccine.

The day after receiving the Oxford / AstraZeneca vaccine, his arm was injured, but soon after he was feeling better. He explained that two friends who received the same vaccine at the same time had flu-like symptoms for 24 hours.

As more Canadians receive each day, some are reporting a host of side effects.

Some people experience mild pain and swelling in the area where they were vaccinated. But fewer may also experience fatigue, headache, muscle aches, chills, fever, or nausea.

These symptoms now bear the unofficial title “vaccine residue”.

Unique immune response

Jason Kendrachuk, assistant professor in the Department of Medical Microbiology and Infectious Diseases at the University of Manitoba, explains that immune systems are complex and very individualized.

“It is difficult to guess how someone would react to something like a vaccination,” he said.

Symptomatic side effects are common after many vaccines, not just those of COVID-19.

Kendrachuk explained that across demographics, including gender and age, there are different immune responses based on biological differences. Some people are more likely to have a strong response to the stimulation of their immune system with the vaccine.

A study published this week in the medical journal The Lancet found that 13.5% of people reported side effects after one dose of Pfizer / BioNTech and 22% reported them after the second dose.

The study found that more people – 37.7% – reported side effects after taking their first dose of AstraZeneca.

Headache and fatigue were more common in women, and any side effects were more likely if people had previously had COVID-19.

The study also found that people under the age of 55 were more likely to experience side effects.

Regardless of the reaction, it works

Dr. Joseph Blondo, Head of the Department of Clinical Microbiology at Royal University Hospital in Saskatoon, thinks this may be because young men have stronger immune systems and are faster to respond.

For stronger side effects in some people when taking their second dose, offer this explanation:

“The body reacts faster and more aggressively because it recognizes something it has already seen and that is what the body is supposed to do.”

Joseph Blondo himself felt more tired and painful than his wife after the vaccination. They both went at the same time and received the same vaccine.

“This doesn’t mean that the reaction was right or wrong, it just means that we are all individuals and we don’t necessarily respond in the same way.”

And if a person does not experience side effects after the vaccine, he or she says this is not a sign that the vaccine is not working.

Dr Blondo suspects that people may also report more side effects than they do with something like the annual flu shot, as there is intense awareness of COVID-19 vaccines and people recognize the importance of helping the world restore some semblance of normality.

While some people may experience symptoms for a few days, Joseph Blondieux explains that the risks of COVID-19 far outweigh these shortcomings.

Craig Silliphant agrees and has some advice for those concerned about side effects.

He says you can find the bright side of your pollen hangover by thinking about how you dealt with alcohol-related pain during your college days.

He laughed, “Make it an excuse to order pizza and spend time on the sofa watching Netflix all day.”