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Long Covid prevalence was highest among US adults ages 35 to 44, according to new CDC research.
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The percentage of US adults reporting long Covid symptoms has fallen since the summer of 2022, but some people say they are still coping with changes to daily life brought on by the condition, according to a new report from the US Centers for Disease Control and Prevention.

The CDC analyzed data from the Census Bureau’s Household Pulse Survey from June 2022 to June 2023. The national survey is designed to measure the social and economic effects of Covid-19 on US households.

Long Covid questions were added to the survey in June 2022. Respondents were then asked to report whether they had ever tested positive for Covid-19 or whether a doctor had ever told them that they had the virus. They were also asked if they had long Covid, which the CDC describes as the “wide range of ongoing respiratory, neurologic, cardiovascular, and other symptoms that can last for weeks, months, or years” after an initial infection.

According to the data, published Thursday in the CDC’s Morbidity and Mortality Weekly Report, long Covid prevalence among all U.S. adults fell from 7.5% in June 2022 to 6% in June 2023.

Among adults reporting previous Covid-19 infections, long Covid prevalence fell from 18.9% to 11% during the study period, the data shows.

Long Covid tended to be less prevalent in the “the youngest and the oldest age groups” of adults reporting previous infections, the CDC researchers noted. Rather, the survey data shows that long Covid prevalence was highest among US adults ages 35 to 44.

The researchers noted that adults 50 and older are more likely to have severe Covid-19 symptoms, but they could not identify whether there is any associated risk between age and long Covid.

The researchers suggest that the decline in overall long Covid cases – particularly in older people – could be due to an overall decline in the prevalence of Covid-19 infections, a decline in severe infections and an increase in preventative measures such as the Covid-19 vaccine.

During the study period, however, about 1 in 4 (26.4%) respondents with long Covid said they had “significant activity limitations,” meaning they have difficulty carrying out day-to-day activities like going to work or to the grocery store.

Overall, the data suggests that this percentage of people with significant changes to daily life did not change over time, the CDC researchers say.

Another data set analyzed by the CDC found that Covid-19 symptoms among adults decreased over time after they had Covid-19, but some participants reported “continuing and/or new symptoms” up to 12 months after an infection.

The Innovative Support for Patients with SARS-CoV-2 Infections Registry or INSPIRE study looked at 1,296 adults who had Covid-19-like symptoms. Participants were tested for Covid-19 at the start of the study and self-reported symptoms at three-month intervals for 12 months.

The data showed that 18.3% of participants who tested positive for Covid-19 reported “persistent symptoms of any type” through 12 months, compared with 16.1% of those who tested negative, according to the study results, which were also published Thursday in the Morbidity and Mortality Weekly Report.

Just over 21% of participants who tested positive listed extreme fatigue as a symptom at the beginning of the study period; 3.5% reported it at the end.

Cognitive difficulties and extreme fatigue were two common symptoms reported six months into the study period, emphasizing the need to better understand post-Covid-19 conditions, the researchers suggest.

“The larger economic and societal impact of long COVID could be far-reaching if working-age adults are unable to maintain employment or care for children or aging parents,” the CDC researchers said, noting that severe long Covid can lead more people to lose their jobs.

Last month, the US Department of Health and Human Services announced the formation of the Office of Long COVID Research and Practice to lead the federal government’s response to long Covid.

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It’s estimated that up to 23 million people in the United States have developed long Covid.

“As our nation continues to make strides in combating COVID-19, it is crucial that we address the impact of Long COVID and provide resources to those in need,” HHS Secretary Xavier Becerra said in last week’s announcement. “Last year President Biden called on HHS to coordinate the response to Long COVID. The Official establishment of the Long COVID Coordinating office and the launch of the RECOVER clinical trials solidifies this issue as an ongoing priority.”

The National Institutes of Health’s RECOVER Initiative, launched in 2021, is a $1.15 billion nationwide research program aimed at better understanding, treating and preventing long Covid.

In May, the initiative published research that identified 12 symptoms that can reliably classify someone as having long Covid: the worsening of health after mental or physical activity; fatigue; brain fog; dizziness; gastrointestinal symptoms; heart palpitations; changes in sexual desire or capacity; loss of or change in taste or smell; thirst; chronic cough; chest pain; and abnormal movements.

More than 200 symptoms are associated with long Covid, and the condition can affect nearly all systems within the body, including the nervous, cardiovascular, gastrointestinal, pulmonary and immune systems.

CNN’s Brenda Goodman and Jacqueline Howard contributed to this report.