Study suggests vaccines may improve symptoms for some COVID-19 long-haulers

Elaine McCartney typically keeps a list on hand of her 30 or so health issues following a bout of COVID-19 a year ago— in part because she just can’t keep track of them all.

There’s the severe fatigue and memory issues. Brain fog, much like after a concussion. Constant headaches, low appetite, round-the-clock dizziness. And on and on.

The 65-year-old from Guelph, Ont., has been experiencing those symptoms for close to a year, after developing what felt like a severe case of influenza in April 2020 and which a physician identified as a probable case of the COVID-19 illness. 

Then last month she got her first dose of the Pfizer-BioNTech vaccine. Her condition quickly seemed to improve.

“I was able to go to the store on my own, which I haven’t done for eight months,” McCartney said. “And my energy was up, and my pain was less. I had chronic debilitating pain in my shoulder, and it was gone.”

McCartney’s experience may offer a glimmer of hope for a growing number of people around the world living with prolonged health concerns after being infected with the virus causing the COVID-19 illness.

She’s not the only patient seeing unexpected improvements. Emerging research suggests vaccines may reduce symptoms for some of those suffering from what is now being called “long COVID”, where patients continue to suffer from a range of health concerns long after the infectious phase of the illness has passed. 

‘Reassuring’ findings from U.K. study

More than a year into the pandemic, it’s not clear how many people are experiencing long-term health issues after having COVID-19, but their numbers are growing.

Researchers think around 10 per cent of people who get sick with COVID-19 continue to live with lasting symptoms — some suggest the number could be as high as 30 per cent — which could mean millions worldwide are coping with some lingering issues from the disease.

A new preprint study out of the U.K., which is still awaiting the peer review process, looked at a small group of such “long COVID” patients. It found those who had received at least one dose of the vaccine had “a small overall improvement” in long COVID symptoms and a “decrease in worsening symptoms” when compared to the unvaccinated patients.

The researchers followed 66 hospitalized patients whose symptoms persisted — issues like fatigue, breathlessness, and insomnia — including 44 who got vaccinated and 22 who didn’t.

A little over 23 per cent of the vaccinated patients saw some resolution of their symptoms, the researchers noted, compared to around 15 per cent of those who weren’t vaccinated — with no difference in response identified between the Pfizer-BioNTech or Oxford-AstraZeneca vaccines used among the participants.

The team also found another “reassuring result” — fewer vaccinated patients reported any worsening symptoms during the time period studied than the unvaccinated group, though they cautioned that there was a large potential for bias given patients self-reported their symptoms. 

Dr. Fergus Hamilton, an infectious diseases researcher at the University of Bristol Medical School and part of the team behind the new study, said the findings offer a “slight hint” that vaccines might improve lingering symptoms.

“Although we’re a bit suspicious about that given the small numbers,” he added.

Science behind vaccine impact not clear

The study is limited by its small sample size, but other medical experts are observing a similar trend.

In the U.S., where roughly a quarter of the population is fully vaccinated, physicians now have a large pool of patients to follow.

Dr. Daniel Griffin, an infectious diseases physician at Columbia University in New York, said around 40 per cent of the patients he is treating for lingering health issues from COVID-19 are reporting either complete, or significant, improvement in their symptoms after being fully vaccinated.

He said the numbers in the U.K. study were “pretty on-target” with what he initially observed in his own patients, but that the impact seemed to bump up a couple weeks after people got their second dose.

“That’s the first bit of good news in a really a long time,” Griffin said.

But he acknowledged the mechanics behind why vaccination might clear up lingering COVID-19 symptoms isn’t yet clear.

WATCH | Long-COVID sufferers struggle with limited care options:

Kim Clark and Sonja Mally have jumped from specialist to specialist for the past year as they’ve sought relief for a series of crippling symptoms associated with post-acute COVID-19 syndrome. Some health experts say more dedicated funding and resources for COVID long-haulers would help sufferers like them and shed light on a little-understood aspect of the pandemic. 2:27

“I think the most persuasive theory for me is that the virus was never completely cleared, or whatever remnants might still be … are now able to be cleared because of the robust response that’s triggered by the vaccines,” Griffin said.

McCartney said her own post-vaccination experience felt nothing short of a miracle — even if the science behind what’s happening in her body remains hazy and more research needed to evaluate how much vaccines could actually help COVID long-haulers going forward.

“I was feeling so miserable, for so long,” she said.

“I’ve logged more than a thousand steps in the past four days and I haven’t done that for months and months and months — so I’ve definitely seen improvement.”