As the coronavirus has spread from person to person over the last year and a half, we have quickly realized that no two infections look the same. While some people are testing positive for the virus without ever experiencing a single symptom, more than 716,000 people in the U.S. have died as a result of their COVID infection, according to the Centers for Disease Control and Prevention (CDC). The virus has even bypassed vaccine protection in some individuals, further reminding us that there is still so much we can't predict about what we might personally experience from a COVID case. On the other hand, new research has found that there is at least one commonality among a majority of people who get infected with COVID.
A new study published Oct. 14 in JAMA Network Open analyzed the various lengths of COVID infections among more than 250,000 virus survivors. The researchers conducted a systematic review of 57 studies to find the proportion of individuals who reported experiencing at least one COVID symptom in three different intervals: short-term at one month, intermediate-term at two to five months, and long-term at six or more months.
According to the study, 54 percent of the study population experienced long-term symptoms for six or more months after COVID diagnosis or hospital discharge. One month and two to five months after infection, 54 percent and 55 percent of the population still experienced symptoms as well, respectively.
"These findings confirm what many health care workers and COVID-19 survivors have been claiming, namely that adverse health effects from COVID-19 can linger," co-lead investigator Vernon Chinchilli, PhD, chair of the Department of Public Health Sciences, said in a statement. "Although previous studies have examined the prevalence of long COVID symptoms among patients, this study examined a larger population, including people in high-, middle- and low-income countries, and examined many more symptoms. Therefore, we believe our findings are quite robust given the available data."
The researchers found that common lingering complications of COVID included weight loss, fatigue, fever, pain, decreased mobility, difficulty concentrating, generalized anxiety disorders, chest imaging abnormality, difficulty breathing, chest pain and palpitations, hair loss, rashes, stomach pain, lack of appetite, diarrhea, and vomiting.
"The burden of poor health in COVID-19 survivors is overwhelming," co-lead investigator Paddy Ssentongo, MD, assistant professor at the Penn State Center for Neural Engineering, said in a statement. "Among these are the mental health disorders. One's battle with COVID doesn't end with recovery from the acute infection."
According to the study, health care providers in the coming years are likely to see an influx of psychiatric and cognitive problems among patients who were otherwise healthy before their COVID infection. The researchers say it is not yet fully known why survivors experience long-term symptoms, but it could be the result of immune-system overdrive, lingering infection, reinfection, or an increased production of autoantibodies.
"Our study was not designed to confirm COVID-19 as the sole cause of these symptoms. It is plausible that symptoms reported by patients in some of the studies examined were due to some other causes," Ssentongo noted.
Regardless, the investigator stressed that the best way to prevent these long-COVID cases is to get more people vaccinated. According to White House COVID adviser Anthony Fauci, MD, there are about 66 million people eligible for vaccinations in the U.S. that still haven't gotten the shot.
"Vaccination is our best ally to prevent getting sick from COVID-19 and to reduce the chance of long COVID even in the presence of a breakthrough infection," Ssentongo said.