For some COVID-19 patients, the initial illness isn’t nearly as bad as the persistent and sometimes disabling symptoms that linger for months or years afterward. These are the people with long COVID, a complex chronic illness that can afflict without regard for age, sex, vaccination status or medical history.
A study of nearly 2 million patients in Israel offers new insights into the trajectory of long COVID, particularly for younger, healthier people whose COVID-19 cases were mild. Researchers found that although most protracted symptoms subsided within a year, some of the syndrome’s most debilitating consequences — namely dizziness, loss of taste and smell, and problems with concentration and memory — still plague a minority of sufferers a full year after the initial infection.
For the study, published Wednesday in the medical journal BMJ, researchers examined the health records of more than 1.9 million members of Maccabi Healthcare Services, one of Israel’s largest health maintenance organizations. Among them were just under 300,000 people who tested positive for the SARS-CoV-2 coronavirus between March 1, 2020, and Oct. 1, 2021, and who were not hospitalized in the first month after infection, a sign that their cases were mild.
The researchers matched each coronavirus-positive subject with an uninfected person in the sample who had the same age, sex and vaccination status and a similar history of risk factors like diabetes, cancer and obesity, among other preexisting conditions. Then the investigators tracked the medical records of both members of each pair to see the health issues they experienced over the following 12 months.