A new study finds that some people experience extended symptoms or "long colds" following various respiratory illnesses, similar to long COVID.
The new study published in The Lancet's eClinicalMedicine journal states that "long colds" tend to last at least four weeks after the initial illness.
The findings suggest that there may be long-lasting health impacts following respiratory infections such as colds, influenza or pneumonia that are currently going unrecognized.
"Our findings may chime with the experience of people who have struggled with prolonged symptoms after having a respiratory infection despite testing negative for COVID-19 on a nose or throat swab," Professor Adrian Martineau, chief investigator of the study, said in a statement.
While long COVID is now a recognized condition, there have been few studies comparing long-term symptoms following SARS-CoV-2 coronavirus infection versus other respiratory infections.
The research compared the prevalence and severity of long-term symptoms after an episode of COVID-19 vs. an episode of another acute respiratory infection that tested negative for COVID-19.
Those recovering from COVID-19 were more likely to experience light-headedness or dizziness and problems with taste and smell compared to those who had a non-COVID-19 respiratory infection.
Some of the most common symptoms of the "long cold" include coughing, stomach pain, and diarrhea more than four weeks after the initial infection.
While the severity of an illness appears to be a key driver of risk of long-term symptoms, more research is being carried out to determine why some people suffer extended symptoms while others do not.
"Our findings shine a light not only on the impact of long Covid on people's lives, but also other respiratory infections," lead author Giulia Vivaldi said. "A lack of awareness—or even the lack of a common term —prevents both reporting and diagnosis of these conditions."
Vivaldi said "long" infections are so difficult to diagnose and treat because patients can have so many possible symptoms and there is a lack of diagnostic tests.
"Ongoing research into the long-term effects of COVID-19 and other acute respiratory infections is important because it can help us to get to the root of why some people experience more prolonged symptoms than others," Martineau added. "Ultimately this could help us to identify the most appropriate form of treatment and care for affected people."