You May Also Get a “lingering Cold” and a “lingering Flu”

You’ve heard of “long COVID,” but COVID isn’t the only disease that can cause long-term symptoms. Other respiratory infections, including colds, flu and pneumonia, sometimes also cause the long version.

This may not be shocking news if you’ve ever noticed that a cough or body aches lingers for some time after you feel recovered from a cold or flu. But until recently this phenomenon was not well studied. As scientists try to understand long COVID, they are starting to learn about long forms of other diseases.

What are the symptoms of a long-term cold and long-term flu?

A new long-term COVID study compared people who had a COVID infection with those who had other respiratory infections (such as a cold) along with a negative COVID test. The researchers’ goal was to find out how long COVID differs from other diseases.

The study looked at surveys of people in the United Kingdom conducted in January 2021, after COVID had been circulating for some time but before most volunteers had received the vaccine. To differentiate long COVID from other post-infectious syndromes, they asked about other infections as well as coronavirus cases.

“Cold cold” is a term that comes from the press release announcing this article, but these non-COVID infections weren’t just colds. These included “pneumonia, influenza, bronchitis, tonsillitis, pharyngitis, ear infection, cold, or other upper or lower respiratory tract infection not caused by SARS-CoV-2.” This means the researchers looked at potentially life-threatening cases: say, pneumonia along with the common cold. That is, this is a large group. So, yes, long-term colds were included in this study, but they were included along with what you might call “long-term pneumonia” and many other things.

The study found that COVID and other respiratory infections can lead to a similar “long-term” syndrome four to 12 weeks after the initial illness. (This is just the time frame they studied; the actual duration of symptoms may have been longer). Symptoms of both long COVID and the “long cold” include:

• Muscle and joint pain
• Sleep problems
• Difficulty concentrating or remembering things
• Lightheadedness and dizziness
• coughing

People with long COVID were more likely to experience decreased sense of smell or taste; this was not as common with other respiratory infections. They also reported more dizziness and dizziness.

Are “long colds” and “long flu” real?

“Cold cold” and “long flu” are not yet universally recognized terms, but the idea that symptoms can persist after infection is not new. A 2022 paper called post-infectious syndromes “a significant blind spot in the medical field.” We know that cases of myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS) can be preceded by infection; It is hoped that research into long COVID may also benefit people who have ME/CFS .

But when people are diagnosed with ME/CFS, they tend to have pretty severe symptoms. The focus on “long COVID” as its own syndrome means that people pay more attention to the lingering symptoms that follow even mild or moderate infections, or when the symptoms themselves are not severe but last a long time.

And as a result of this focus on long COVID, researchers in a recent Lancet paper found that they need to ask what symptoms people experience after other infections to distinguish them from long COVID. They found many similarities between the two, suggesting that the “long cold” had been flying under the radar for some time, along with what we might call the “long flu”, “long pneumonia” and others.

It’s important to note that the new study has limitations when comparing long-term COVID with other syndromes. Diagnosis was largely self-made, and a person who had COVID but received a false negative COVID test result would be counted among “other” infections. (Critics have also questioned whether comparing “long COVID” to “long colds” minimizes or downplays the experience of patients with severe long COVID; I disagree with this formulation, but think it’s important to note that these non-COVID infections and their post-infectious symptoms are not necessarily mild.)

However, we are learning more about how the human body can respond to infection, and this is an area worthy of further study. Researchers in a recent paper write:

“Lack of awareness of the post-acute consequences of other [acute respiratory infections]—or even the lack of a common term such as “long COVID”—is likely to contribute to underreporting.”

If this is true, then simply giving long colds a name is a step toward better understanding them.