The coronavirus vaccines may ease symptoms of long Covid, new research suggests, with more than half of participants reporting improvements after a jab. 

Conducted by the patient advocacy group LongCovidSOS, in collaboration with Dr David Strain at the University of Exeter Medical School and Dr Jeremy Rossman at the University of Kent, the study surveyed more than 800 people about their symptoms before and after vaccination. 

It looked at before and after scores across 14 common long Covid symptoms, such as fatigue and memory fog. 

Over half (57%) of participants reported an overall improvement in their symptoms, with 24% reporting no difference and 19% deteriorating. 

However, it’s worth noting that only 3% said all of their symptoms had  worsened, and this was often transiently. 

The research, which has not been peer reviewed, follows concerns in the long Covid community that by stimulating the immune response, vaccination could exacerbate symptoms.

Ondine Sherwood, from LongCovidSOS, said she hopes those impacted by long Covid would be “reassured by the results of this survey, and [not] hesitate to have any of the vaccines on offer”.

“These data show that many people do improve after vaccination and only a small proportion get worse,” she added. “These changes might be temporary for some people. We hope that this information will lead to controlled clinical trials so that we can find out whether vaccines might have therapeutic use for those with long Covid.”

The research can’t say for certain whether the vaccines ease long Covid symptoms, or if people are simply recovering over a period of time. However, there was some evidence to suggest that people experience a reduction in symptoms after one vaccine, a slight resurgence while waiting for their second jab, then a second easing of symptoms after their second injection. 

In general, those who received mRNA vaccines (Pfizer or Moderna) reported more improvements in symptoms, compared with those who got an adenovirus vaccine (AstraZeneca). The survey found:

• The Moderna vaccine reduced the average symptom score by 31% of the prior symptoms, closely followed by Pfizer at 24.4% and the AstraZeneca at 23%.

• There was a “significant advantage” from receipt of the Moderna vaccine with respect to fatigue, myalgia/muscle pain and chest pain when compared to the AstraZeneca vaccine. 

• Approximately half of the people in the survey suggested that their symptoms were returning to their baseline at time of response, with the other half having had a sustained benefit.

“The vaccination programme is vital in preventing reinfection for people with Long Covid,” said Dr Strain of the University of Exeter Medical School. “These results do give cause for cautious optimism.

“Despite all of the caveats around observational data, self-reporting of symptoms and a lack of time control, the overwhelmingly positive response in people who had been suffering for up to 12 months, suggests that, at worst, vaccination will not cause a deterioration for those living with long Covid, and potentially may be of benefit.

“If confirmed, this benefit could provide hope for many more, as it demonstrates that for some people, long Covid does respond to treatment, and now we need to explore alternative therapeutics for the rest.”