A study published on JAMA Network Open has shed new light on the phenomenon known as "long COVID," indicating that long-lasting symptoms following viral illness are actually more common among non-COVID respiratory illness than they are following COVID-19 infection.

Long COVID is generally understood to refer to symptoms that persist beyond four weeks after acute COVID infection, most commonly including fatigue, cognitive impairment, and malaise following physical exertion. It was previously believed to affect up to a half of all COVID-19 patients, and vaccination was promoted as a means to combat it. However, a huge study of over 13 million people published in Nature several months ago found that vaccination against COVID has only a minimal effect on progression to long COVID.

The JAMA study enrolled a thousand adults with acute symptoms "suggestive of SARS-CoV-2 infection" who were then tested for COVID-19. 72.% of study participants tested positive; the remaining 27.8% tested negative. They were then surveyed at baseline and at the three-month mark, using a common scale known as PROMIS-29 which asks respondents to describe 29 different symptoms such as anxiety, depression, fatigue, social participation, pain, and sleep disturbance.

At the three-month mark, 39.6% of the participants in the COVID-19-positive group reported persistent poor physical, mental, or social well-being, as opposed to 53.5% of the COVID-19-negative group.This was despite the fact that the COVID-19-positive participants had more symptoms at baseline and were more likely to have been hospitalized for their symptomatic illness.

The study's authors add that following "adjustment," only social participation scores were statistically greater in the COVID-19-positive group. They also note that the "presence and persistence of poor mental health among nearly 1 in 4 participants (21.9% of the COVID-19–positive group and 27.3% of the COVID-19–negative group) may reflect a more general pandemic exposure, which participants in both groups experienced."