(HealthDay News) — Long COVID symptoms can persist for up to 12 months, according to research published in the Aug. 11 issue of the US Centers for Disease Control and Prevention Morbidity and Mortality Weekly Report.

Juan Carlos C. Montoy, MD, PhD, from the University of California in San Francisco, and colleagues analyzed data on self-reported symptoms from 1,296 adults with COVID-like illness who were tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The researchers observed a substantial decrease in the prevalence of any symptoms between baseline and three-month follow-up, from 98.4 to 48.2% and from 88.2 to 36.6%, respectively, for those who received a positive and a negative SARS-CoV-2 test result. Through 12 months, there was a decrease in persistent symptoms; at 12 months, there was no difference seen between the groups. Symptoms that emerged or reemerged at six, nine and 12 months were reported in both groups.

Nicole D. Ford, PhD, from the CDC in Atlanta, and colleagues estimated the prevalence of long COVID using data from surveys completed between June 1 to 13, 2022, and June 7 to 19, 2023. The researchers found that the prevalence of long COVID decreased from 7.5 to 6.0% among the overall US adult population and from 18.9 to 11.0% among US adults reporting previous COVID-19. Prevalence decreased from June 1 to 13, 2022, through Jan. 4 to 16, 2023, among both groups, before stabilizing. Overall, 26.4% of adults with long COVID reported significant activity limitation during June 7 to 19, 2023; the prevalence did not change over time.

“These findings highlight the importance of COVID prevention, including staying up to date with recommended COVID-19 vaccination,” Ford and colleagues write.

Several authors from the Montoy study disclosed ties to the diagnostics and medical technology industries.

Abstract/Full Text – Montoy

Abstract/Full Text – Ford