The Pros and Cons of Getting Vaccinated This Holiday Season

It feels like we’ve been listening to holiday music for a month already. Does that mean you’ve missed the window to get your seasonal vaccines? “Not at all,” says Dr. Marc-André Langlois, Professor in the Faculty of Medicine at the University of Ottawa and CoVaRR-Net Executive Director. “With the hustle and bustle of the holiday season, it’s just a matter of time before we all get infected.”

Battling the flu & COVID-19

In a pattern that has been observed for over 100 years, flu season is once again upon us. And while there are rare cases where the virus can cause severe complications, most of us will recover from an infection unscathed. So, what are the benefits of getting vaccinated? A simple jab can reduce the severity and duration of your flu symptoms and help you get back to your festive activities. It will also reduce your chances of transmitting the virus to Grandma, who may not recover as easily.

When it comes to COVID-19, don’t be fooled by the lack of press. It is still around, and it’s here to stay. In fact, the latest reports indicate that on 96% of flights, there is an individual infected with COVID-19 on board. So, if you’re planning on flying this holiday season, you ought to consider protecting yourself by getting vaccinated and wearing a mask on your flight.

And while we expect COVID-19 to follow seasonal patterns similar to influenza, that’s where the similarities end. “We now know, after intensive study of the virus, that it is not just like the flu,” states Dr. Langlois. “It is a multi-system disease that can affect your nervous and vascular systems as well as various organs including your heart, lungs, brain, and kidneys. It can also affect your mental fitness, reducing your energy and ability to concentrate.”

Furthermore, research now shows that the more times you are re-infected, the more likely you are to develop long COVID. For example, those who had two COVID infections are more than twice as likely to develop long COVID. Those with three or more infections are almost four times more likely to develop it. But more on that a little later…

So which vaccine to get?

For the 2024-2025 influenza season, the National Advisory Committee on Immunization (NACI) continues to recommend the age-appropriate quadrivalent or trivalent influenza vaccine for individuals aged 6 months and older who have no contraindications or precautions. Because the virus evolves so quickly, a new composition is needed each year.

Similarly, for fall 2024, NACI has recommended two updated mRNA vaccines against SARS-COV-2, both targeting the KP.2 strain. Moderna Spikevax is available for aged 6 months and over, and Pfizer-BioNTech Comirnaty is available for those 12 years and older. The difference between the two is negligible and you should feel comfortably protected after taking either one. NACI has also recommended Novavax’s Nuvaxovid, a protein-based vaccine, for those aged 12 and older, but it is not widely procured and sent to provinces due to low demand in previous years.

Can you get your flu and COVID-19 shots at the same time?

Currently, there is no evidence that it is better or worse to have them at the same time. “I would rather have a sore arm once for two days than twice for two days,” says Dr. Langlois, rather pragmatically. “I would rather wait at the pharmacy once. It’s purely a matter of convenience.”

Although this is the current state of knowledge, he admits we need to conduct more randomized clinical trials to establish whether co-administration (at the same time) or sequential administration produces an identical, a similar or slightly different immune response.

Co-administration versus sequential, a clinical trial

In an ongoing, CIHR-funded clinical trial for which Dr. Langlois is a co-investigator dubbed “The Best Shot for What You’ve Got,” Dr. Ruth Sapir-Pichhadze and her team at the Centre for Outcomes Research and Evaluation (CORE) at the Research Institute of the McGill University Health Centre (The Institute), aim to identify strategies to improve the protective immune response to respiratory vaccines in people living with immunocompromising conditions.

The 2024 summer surge in COVID-19 hospitalizations highlighted once again the continuing vulnerability of people living with immunocompromising conditions, such as solid organ transplant recipients taking immunosuppressive drugs, or people living with inflammatory bowel disease, rheumatological diseases or chronic viral diseases such as HIV. They are at increased risk of developing serious infections requiring additional treatment or hospitalization.

Dr. Sapir-Pichhadze’s team is investigating whether co-administration of the COVID-19 vaccine, together with the seasonal inactivated influenza vaccine, is as effective as sequential administration. “As COVID-19 disease moves from the context of a pandemic to an infection that tends to occur alongside the flu season, it is important to outline preventive strategies that take both into account,” explains Dr. Sapir- Pichhadze.

Long COVID

Unfortunately, no matter which COVID-19 vaccine you get or how you get it, neither of them prevent infections very well. However, what they do well is reduce the severity and duration of your symptoms and shorten the period in which you are contagious. But most importantly, vaccines have been shown to reduce your chances of developing long COVID.

“For about 1 in 6, or 17% of Canadians, a COVID-19 infection can result in long COVID,” says Dr. Nazeem Muhajarine, Co-Lead of CoVaRR-Net’s Public Health, Health Systems and Social Policy Impacts Pillar 8, Professor, and epidemiologist at the University of Saskatchewan.

“While there is a whole spectrum of severity of long COVID, it can result in debilitating symptoms for months, if not years. It can set you back in terms of your work, being physically active, being cognitively sharp, and being able to relate to people, for example, hug your grandchildren, get together and carry a conversation with your friends through an evening.”

Regrettably, Dr. Muhajarine says we still can’t conclude for sure who is at greater risk for long COVID because the manifestation is broad and seems to depend on several factors related to the patient, the virus and COVID-19 itself. “Physiologists, immunologists and public health researchers will be studying long COVID for some years to come.”

Better safe than sorry?

Cecilia Jenkins has been the Network Operating Officer at CoVaRR-Net since May 2021. A scientist in her own right, with a PhD in mineral engineering, you might assume she follows the science and gets vaccinated at every opportunity. And you would be right.

“I had both my COVID and flu shots, boom boom, on a Monday afternoon. Tuesday my arm was sore, took two acetaminophen tablets, and Wednesday it had improved. By Thursday, I was even better.”

Although Cecilia is a firm believer in the benefits of vaccination, she still looks forward to a time when she doesn’t have to take a COVID shot every year, perhaps with the advent of a mucosal vaccine.

Mucosal vaccines represent an altogether new category of vaccine technology – one that several CoVaRR-Net researchers are trying to develop – that not only reduces the severity and length of disease, but BLOCKS infection entirely. They are vaccines delivered via a nasal spray or inhaled to induce a protective immune response at the site of virus entry. This way, the virus that enters your airway doesn’t even get a chance to attach itself and infect a cell.

Until then, Cecilia, an independent, competitive, healthy, athletic, 62-year-old woman is doing everything she can to avoid her biggest worry: long COVID. “I work from home. I get vaccinated. I wear masks everywhere. If I get infected, it will be because I’ve chosen to take a risk,” says Cecilia. “People say I’m missing out. Well, yes and no. If I got COVID, would I be able to do all the mountain biking that I do as a 62-year-old lady, still riding a 26er when everybody’s gone e-biking? I don’t think so.”

While the risk of long COVID is a compelling enough reason for many of us to get vaccinated, why do others resist?

Though the answer is no doubt multifaceted, Dr. Nazeem Muhajarine and his Pillar 8 compatriots have spent their final year with CoVaRR-Net unpacking the concept of public trust and how it has changed as a result of the COVID-19 pandemic.

“I think we are at a critical point in terms of public trust,” Dr. Muhajarine explains. “In many cases, how people feel about vaccines and COVID-19, and maybe even future health emergencies, is influenced by how they feel about government, public health authorities, health scientists and medical care providers, not to mention politicians. Moving forward, we have to work to retain people’s trust, so they will trust us, as trust is a two-way street, and we cannot ignore our part in this.”