New research offers fresh clues to targeting long Covid. Photo / Getty Images
Jenene Crossan was among the first New Zealanders to develop long-Covid after contracting Covid-19 during an overseas trip in early 2020. There was an expectation that she and other sufferers would eventually get better, but for many, that hasn’t been the case. If anything, Crossan’s health has worsened, as she has developed autoimmune disorders triggered by the virus.
“Recently, I had a myositis diagnosis,” she says. “It’s an autoimmune condition that causes chronic inflammation and weakness in the muscles.
“I used to be a boot camp girl and ran half-marathons. Now, if I go out shopping in the morning, I’m so shattered I have to lie on the couch for the rest of the day.”
When researchers at the University of Oxford looked at 475 people who had been hospitalised with Covid-19 in the first wave of the virus before vaccines were available, they found that many symptoms worsened over the following two to three years and some participants reported new symptoms.
“I was expecting to see a gradual improvement,” admits Maxime Taquet, lead author of the study, published in the Lancet. “I wasn’t expecting that on average people would be getting worse.”
Most participants reported at least mild symptoms, including depression, anxiety, fatigue and cognitive decline, and more than one in five experienced severe symptoms. For a quarter, the impact on their health resulted in them changing their occupation.
Cognitive testing confirmed brain function had been affected. Many participants had IQ scores that were lower than expected considering their age, education and other factors.
“We didn’t have data for these participants from before they had Covid-19, for obvious reasons,” says Taquet. “But we did have access to data from a large population of people who didn’t have Covid and completed the same test as part of the Great British Intelligence Study and we were able to use that for comparison. We found, on average, our participants were about 10 IQ points below the expected level.”
The testing took place online, but Taquet did have contact with some members of the cohort.
“One that really stuck with me was a man who was high achieving and had a very important job but had to stop because he couldn’t meet the demands of that job. This is the impact the cognitive deficit can have on people’s lives.”