There Really Is Such a Thing As Long Flu!

One of the most devastating consequences of COVID-19 infections is what doctors call post-acute sequelae of COVID-19 (PASC). Patients refer to this condition more succinctly as Long COVID. A study demonstrates that COVID-19 is not the only infection that can lead to long-lasting complications. There may also be “long flu.” In other words, some people may experience long-lasting symptoms after “recovering” from influenza and other respiratory tract infections. People with chronic fatigue syndrome (CFS) feel vindicated…after 35 years!

A Story of Long Flu:

Q. Twenty years ago, after an upper respiratory infection, I suddenly went from being a high-energy person to someone who could not get out of bed. I couldn’t lift my head off the pillow without experiencing POTS.

The fatigue is better, although my very fast heart rate makes it hard to exert myself. The shortness of breath and sleep problems are annoying, but the neurological symptoms are the worst. Besides brain fog, I have neuropathy.

When all this started, I read that neurological symptoms are often part of the profile for chronic fatigue syndrome. I have been wondering if that is what I have, but I haven’t been able to find out anything more. What can you tell me?

A. When you developed an upper respiratory tract infection 20 years ago, most physicians did not recognize that such flu-like illnesses might lead to long-lasting complications. A study in Lancet Infectious Diseases, Dec. 14, 2023, reveals that both COVID-19 and influenza can cause neurological symptoms as well as fatigue.

The authors of this study are calling the condition “long flu.”

You mention POTS–postural orthostatic tachycardia syndrome. This condition, which is common in both long COVID and chronic fatigue syndrome (CFS), seems to be a dysfunction of the autonomic nervous system. Heart rate increases rapidly when a person stands up, and they often feel dizzy. Sadly, there is not yet a cure for long COVID, long flu or CFS, even after many decades.

Long Flu or Chronic Fatigue Syndrome?

We were among the first health journalists to discuss a mysterious viral condition that led to long-lasting complications. In the spring of 1988, we interviewed Dr. Paul Cheney on our radio show, The People’s Pharmacy. He was a brilliant scientist with an MD and a PhD (physics). At one time in his career, he was a research associate at the CDC’s Division of Immunology.

We became interested in Dr. Cheney after he reported a strange syndrome in his medical practice at Incline Village (near Lake Tahoe), Nevada. It was the late 1980s and there had been a bad winter flu season in his community.

An article about his contribution to medicine describes it this way (Integrative Medicine: A Clinician’s Journal, Oct. 2017):

“Chronic fatigue syndrome (CFS) has remained a medical enigma since it was first reported in the late 1980s by Paul Cheney, MD, PhD, who—along with his medical partner in Incline Village, Nevada—made the observation of a group of his patients all having serious and unremitting fatigue following a significant winter flu season.

“During the 1990s, there was considerable discussion about the etiology of CFS, which is commonly referred to as myalgic encephalomyelitis (ME) in the United Kingdom. CFS/ME is now recognized to be a complex, chronic medical condition. It is characterized by a symptom cluster presenting as pathological fatigue and malaise that is worse after exertion, cognitive and immune dysfunctions, muscle pain, lymphadenopathy, and sleep disturbances. It is estimated that between 1 and 2.5 million people in the United States have this condition, resulting in an annual treatment cost of $17 to $24 billion dollars.”

Why Didn’t Infectious Disease Experts Recognize Long Flu?

Dr. Cheney was a true pioneer in the chronic fatigue syndrome (CFS) field! But his description of long flu symptoms did not endear him to infectious disease experts. They had a hard time wrapping their heads around the concept of chronic fatigue syndrome.

No one could identify a pathogen. Without a smoking gun causative factor, most experts denied CFS existed. A majority of physicians at the time considered the condition psychosomatic. In other words, it was all in peoples’ heads.

The CDC now recognizes ME/CFS as a:

“…complex, chronic, debilitating disease associated with multiple pathophysiological changes that affect multiple systems.

“ME/CFS affects between 836,000 and 2.6 million Americans of all ages, ethnicities, races, and socioeconomic groups.

“While the cause of the disease remains unknown, onset may follow an ‘infectious-like’ syndrome.”

Is It Long Flu?

Dr. Paul Cheney was decades ahead of his time. What he was describing back in the 1980s seems a lot like the condition we now call long COVID. In other words, the post-acute sequelae of COVID or PASC are somewhat similar to the complaints Dr. Cheney’s patients voiced more than four decades ago.

I am not suggesting that CFS is the same as long COVID. What I am suggesting, though, is that some people experience long-lasting symptoms after viral infections from SARS-CoV-2, influenza virus or some other mysterious pathogen.

The latest research on the likelihood of long flu comes from Washington University School of Medicine in St. Louis and the Veterans Affairs St. Louis Health Care System (Lancet Infectious Diseases, Dec. 14, 2023). An analysis of more than 90,000 health records from the VA reveals that people recovering from seasonal influenza may also be at risk for premature death and hospital readmission.

Here is how the lead author describes the research (News Release, Washington University School of Medicine in St. Louis, Dec. 14, 2023):

“The study illustrates the high toll of death and loss of health following hospitalization with either COVID-19 or seasonal influenza.

“It’s critical to note that the health risks were higher after the first 30 days of infection. Many people think they’re over COVID-19 or the flu after being discharged from the hospital. That may be true for some people. But our research shows that both viruses can cause long-haul illness.”

It IS Long Flu!

The investigators tracked patients for up to 18 months after recovery from the initial infection. Although COVID-19 led to more serious problems than influenza, both infections have a long tail. That is, the persistent complications far outweighed the health problems during the initial hospitalizations.

The researchers are now calling the continuing complications of influenza “long flu.” They warn their colleagues to recognize that some patients end up with serious long-term health problems after both COVID and influenza.

The lead author describes the thinking behind Long Flu:

“Our novel approach compared the long-term health effects of a vast array of conditions. Five years ago, it wouldn’t have occurred to me to examine the possibility of a ‘long flu.’ A major lesson we learned from SARS-CoV-2 is that an infection that initially was thought to only cause brief illness also can lead to chronic disease. This revelation motivated us to look at long-term outcomes of COVID-19 versus flu.

“We wanted to know whether and to what degree people with flu also experience long-term health effects,” Al-Aly said. “The big answer is that both COVID-19 and the flu led to long-term health problems, and the big aha moment was the realization that the magnitude of long-term health loss eclipsed the problems that these patients endured in the early phase of the infection. Long COVID is much more of a health problem than COVID, and long flu is much more of a health problem than the flu.”

Final Words About Long Flu:

Early in the COVID pandemic we heard from a lot of people that COVID was no worse than the flu. That turned out not to be the case. COVID-19 is much worse than influenza. The research from Washington University School of Medicine and the Veterans Affairs St. Louis Health Care System established that. But long flu should now be recognized as a real problem in its own right.

Here again is the lead author describing the findings of the latest study (Lancet Infectious Diseases, Dec. 14, 2023) in the News Release from Washington University School of Medicine:

“The idea that COVID-19 or flu are just acute illnesses overlooks their larger long-term effects on human health,” Al-Aly said. “Before the pandemic, we tended to belittle most viral infections by regarding them as somewhat inconsequential: ‘You’ll get sick and get over it in a few days.’ But we’re discovering that is not everyone’s experience. Some people are ending up with serious long-term health issues. We need to wake up to this reality and stop trivializing viral infections and understand that they are major drivers of chronic diseases.”

What Do You Think?

Please share your thoughts about long flu or chronic fatigue syndrome. Do you know someone has experienced long COVID, long flu or CFS? We welcome your story in the comment section below.