By now, it’s abundantly clear that COVID-19 is not always an illness that clears quickly and leaves no trace. Long COVID-19 is the term for symptoms that can last up to a year or more after an infection. It affects millions of Americans in America.
A new U.S. Centers for Disease Control and Prevention report (CDC) has now quantified how frequently COVID-19 can be linked to health problems. According to the report, one-fifth of Americans aged 65 and younger have developed health conditions that could be linked with COVID-19. The rate is about 1 in 4 among people over 65.
Researchers at CDC used electronic health records (eHRs) to find more than 350,000 COVID-19-positive adults in the United States. They tracked these people for up to a year after their diagnoses to see if they developed at least one of 26 conditions linked to post-COVID-19 illness—including heart disease, respiratory problems, asthma, kidney disease, neurologic conditions, diabetes, and mental health conditions. They also followed 1.6 million U.S. adults, who were not diagnosed with COVID-19 but received medical treatment for another reason during their study.
This comparison showed that COVID-19 patients were much more at risk for almost all 26 of these conditions. Most significant differences in risk between COVID-19 victims and the general public were for developing respiratory symptoms, and pulmonary embolisms (a form of blood clot that causes chest pain and shortness-of-breath). People who’d had COVID-19 were about twice as likely to develop both conditions.
The data had some limitations. Because the researchers only used one particular electronic health record network to collect data, the sample may not have been representative of all Americans. It’s also possible that doctors were looking more closely for the analyzed conditions in COVID-19 survivors than in those who hadn’t had the virus, or that some people had undiagnosed conditions before they got infected. People with any documented history of any 26 condition were not included in the study. The researchers also didn’t account for a person’s COVID-19 vaccination status, and data collection ran only through November 2021, so it’s impossible to say how newer COVID-19 variants like Omicron fit into the picture.
However, this study proves that COVID-19 can lead to problems lasting much longer than an acute illness. Even if symptoms like coughing, fever, and fatigue clear up in a matter of days, the virus can leave a lasting mark in ways that aren’t immediately apparent.
That’s cause for serious concern, particularly given how contagious the currently circulating variants are. According to CDC, almost 60% of U.S. citizens had been infected at the end of February. That number may rise further. “As the cumulative number of persons ever having been infected with SARS-CoV-2 increases, the number of survivors suffering post-COVID conditions is also likely to increase,” the authors of the new report write.
These conditions can be serious or even debilitating—some with Long COVID have had to leave their jobs or drastically change their lifestyles—and it’s not always possible to predict who will be affected. Experts often recommend that you avoid getting the COVID virus and get vaccinated.
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