The medical community has recognized post-viral syndrome for decades, and it has been well-documented and confirmed with scientific research.[1] Exactly how to categorize it remains controversial, though. 

Although one perspective continues to claim it is primarily psychogenic (psychological origin), there are real physical changes that can be measured, so it’s definitely not just “all in your head.” 

Typically, in post-viral syndrome an acute flu-like illness that may not have been specifically diagnosed is followed by unexplained, continuous or relapsing fatigue that causes the person to reduce his or her normal activities. 

In addition, a constellation of other signs and symptoms will be present that aren’t the same for everyone but show a recognizable pattern. Under the UK definition, these symptoms must last for at least four months; under the US definition, they must last six months or more.[2]

In technical terms, post-viral syndrome occurs when a long-term state of fatigue characterized by post-exertion neuroimmune exhaustion follows recovery from an acute illness.

Some voices in the medical field have equated post-viral syndrome with Chronic Fatigue Syndrome (CFS), pointing out that the signs and symptoms are virtually identical. Others note that not every case of CFS can be traced back to an original acute illness. 

For now, it probably makes sense to consider post-viral syndrome as a subcategory of CFS. 

By the way, the official international terminology for CFS is CFS/ME. In the United States, the condition has been known primarily as CFS, but in Europe, it was called Myalgic Encephalomyelitis, a term that emphasizes muscle pain and central nervous system involvement over the main symptom of fatigue. 

If you think you have post-viral syndrome, reading more about CFS/ME will probably be useful to you. Just remember that you have the extra factor of a previous infection to consider when seeking to understand how your symptoms developed and deciding what to do about them.

Furthermore, if you have been diagnosed with long-haul COVID, you and your practitioner may find it helpful to use existing therapies for post-viral fatigue, myalgic encephalomyelitis, and/or chronic fatigue syndrome. 

Decades of research links PVFS to a variety of infections caused by both viruses and bacteria. After polio, one of the first viruses to be recognized as causing the pain and fatigue in some CFS patients was Epstein-Barr Virus (EBV), the pathogen that causes mononucleosis. In the 1980s, some scientists zeroed in on EBV as the single cause of CFS, but more research found that not every CFS patient had EBV antibodies. [3]

Since then, a number of other viruses and bacteria have been identified that can lead to post-viral syndrome, including: [4]

•         Coxsackie virus (causes Hand, Foot, and Mouth Disease)
•         Varicella-zoster virus (causes chickenpox)
•         Enterovirus (causes “stomach flu” and colds)
•         Influenza
•         Human parvovirus (causes Fifth disease)
•         Human herpesvirus 6 A or B (HHV-6 B causes roseola in babies and toddlers) 
•         SARS-CoV and SARS-CoV-2 (cause SARS and COVID-19)
•         Rubella (causes German measles)
•         Borrelia (causes Lyme disease)
•         Mycoplasma pneumoniae (causes “walking pneumonia”)

By the time most people reach adulthood, they’ve probably been infected by one or more of these microbes. Obviously, not everyone has “long-haul” symptoms after an infection. But in some cases and for some people, chronic symptoms can develop and hang on for months or years.

Here are the most common symptoms of PVFS, which have been recognized as part of the diagnostic criteria since 1990. [5]

•         Exhaustion, especially after exercise or activity
•         Fatigue
•         Muscle pain
•         Mild fever
•         Sore lymph nodes
•         Sore throat
•         Headache
•         Light sensitivity
•         Dizziness or feeling off balance
•         Sleep disturbances (sleeping a lot, unrefreshing sleep)
•         Night sweats
•         Difficulty concentrating
•         Poor memory
•         Depression
•         Mood swings
•         Irritability
•         Irritable Bowel Syndrome

Because there’s no lab test that can confirm PVFS or CFS, doctors rule out other causes of the symptoms and look for a cluster of symptoms affecting different body symptoms when they make a diagnosis. 

If you’ve experienced at least six months of fatigue that has interfered with your life, your doctor may determine that you have PVFS or CFS if you have at least four of these symptoms: “post-exertional malaise (PEM) lasting more than 24 hours; substantial impairment in short-term memory or concentration; sore throat; tender lymph nodes; muscle pain; multi-joint pain without swelling or redness; headaches of a new type, pattern, or severity; and unrefreshing sleep.”[6]

A lot of disagreement remains about just how a viral or bacterial infection can trigger the long list of symptoms that someone with PVFS can have. Despite volumes of research, no one has developed the perfect explanation yet. For now, most of the ideas remain hypotheses that have yet to be fully proven.

These are some areas of the body that seem to be involved in post-viral fatigue.

Immune system. One of the earliest findings about people who had post-viral fatigue was that they had alterations of their lymphocytes, or white blood cells. That’s not surprising since the pathogen triggers an immune response. But not all people with PVFS have the same changes to their immune cells. One theory is PVS is an autoimmune disorder where the overactive immune system mounts a response against its own cells and organs. Many studies have investigated the role that immune-related pro-inflammatory cytokines play in PVFS, but the results are inconclusive.

Nervous System. The international diagnostic classification categorizes PVFS as a nervous system disorder. Muscle pain, poor concentration and memory, and irregular sleep patterns are all related to the nervous system. Research shows that the autonomic nervous system (ANS), which controls background functions like breathing and heartbeat, functions differently in people with CFS.

For example, people with CFS seem to have less heart rate variability while they sleep, which could be related to less restful sleep.[7] The vagus nerve, which is part of the ANS, also interacts with the immune system. When it senses cytokines in one part of the body, it can communicate with the brain stem to produce a “sickness response.” One medical hypothesis proposes that infection of the vagus nerve by latent microbes could be the cause of PVFS symptoms. [8]

Mitochondria. Mitochondria are organelles that have been called the “powerhouse of the cell” because they produce energy in the form of adenosine triphosphate (ATP). Since fatigue and low energy are the key symptoms of CFS/ME, researchers have studied mitochondria for clues. People with CFS don’t have genetic problems with their mitochondria, but many studies have found changes in mitochondrial function. In particular, lower levels of CoQ-10, a co-enzyme involved in ATP production, were found to be lower in those with CFS. [9]

Lymphatic System. Swollen and painful lymph nodes, a key characteristic of PVFS, are an objective sign that supports the organic rather than psychogenic nature of fatigue syndromes. Doctors can conduct a physical scan of tender points and specific lymph nodes to help confirm their diagnosis. [10] Lymphatic drainage is important to recovery from PVFS, but that requires moving around, and malaise after exercising is part of the syndrome, so finding a balance is important. Self-massage techniques and gentle movements throughout the day can improve your lymphatic system’s ability to clear toxins out of your body.

[RJ note: I’d really like to have a page of self-massage to link to, but I couldn’t find anything I like. Maybe you can find something.]

Post-exertional malaise (PEM) is a hallmark of PVFS, so if you have this condition, it’s not reasonable to expect that you can exercise like others. How much CFS patients should exercise has ignited an ongoing controversy in the medical profession. An approach called graded exercise therapy (GET) seemed to be supported by research, but it was subsequently criticized by doctors who specialize in treating CFS patients. In 2008, the M.E. Association found that most of the doctors surveyed found GET to be unsuccessful or even harmful.

While those with mild CFS, especially younger people who are recovering, may benefit from gradually increasing exercise, those with moderate or severe symptoms should embark on a mild stretching program first. As recommended by the American Myalgic Encephalomyelitis and Chronic Fatigue Syndrome Society, those who are ready can begin very short, sub-aerobic walks of a few minutes at a time. When they are able to tolerate a five-to-seven-minute walk, they can try yoga and weightless muscle-strengthening exercise. 

Learning to listen to your body will help you benefit from movement without crashing from doing too much.

While eating well is good for everyone, it’s even more important for those with chronic health issues. A diet high in fats, refined carbohydrates, and artificial ingredients can make anyone feel sluggish. If you’re already fatigued, you want to eat foods that will give you more energy—if that’s possible.

Your main focus should be eating foods in their near-natural state. Many raw foods contain the enzymes that will help you digest them, so fresh fruits and vegetables make great choices. They have the added benefit of requiring no or little preparation. Berries, bananas, oranges, and apples make great go-to items. Keep a stock of munchable veggies like carrots, bell peppers, pea pods and jicama with hummus or guacamole to dip them in. Yogurt, trail mix, and granola are other easy-to-grab mini-meals that are packed with nutrients.

When you’re up to doing a few minutes of food preparation, eggs, oatmeal, and brown rice or quinoa can form the basis of a quick and satisfying lunch or supper.

Nowadays, there are many food-delivery services, including several healthy and organic options. If you can afford it, doorstep service means you don’t have to use up your energy shopping. Having some of these meals in the freezer can make all the difference after an especially exhausting day. Personally, we like Daily Harvest. 

Don’t forget to stay hydrated. A good rule of thumb is to drink half your weight in ounces each day of pure water. For example, if you weigh 130 pounds, you need 65 ounces of water a day. Many people fill up their favorite water bottle in the morning, at lunch, and after supper and keep it constantly by their side to remind themselves to keep sipping.

The lingering effects of a past viral or bacterial infection put unusual stress on the body. Natural nutritional supplements can help restore balance when nutrient stores have been depleted from ongoing physical stressors. Obviously, it’s important to work with a healthcare professional to receive a diagnosis and recommendations for supplements that can help you. 

From years of working with post-viral fatigue sufferers, we’ve found the products below can help reduce symptoms and improve energy levels. Combined with other targeted therapies, they can help put you on the road to recovery.

1. Archer MI. The post-viral syndrome: A review. J R Coll Gen Pract. 1987;37(298):212-214.

2. Hives L, Bradley A, Richards J, et al. Can physical assessment techniques aid diagnosis in people with chronic fatigue syndrome/myalgic encephalomyelitis? A diagnostic accuracy study. BMJ Open. 2017;7(11):e017521. Published 2017 Nov 13. doi:10.1136/bmjopen-2017-017521

3. Bannister BA. Post-infectious disease syndrome. Postgrad Med J. 1988;64(753):559-567. doi:10.1136/pgmj.64.753.559

4. Rasa S, Nora-Krukle Z, Henning N, et al. Chronic viral infections in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). J Transl Med. 2018;16(1):268. Published 2018 Oct 1. doi:10.1186/s12967-018-1644-y

5. Behan PO et al. Enteroviruses and Postviral Fatigue Syndrome. In Bock, G.R.; Whelan, J. (eds.). Ciba Foundation Symposium 173 ‐ Chronic Fatigue Syndrome. 2007. doi:10.1002/9780470514382.ch9

6. Fukuda K, et al. The chronic fatigue syndrome: A comprehensive approach to its definition and study. International Chronic Fatigue Syndrome Study Group. Ann Intern Med. 1994;121(12):953-959. doi:10.7326/0003-4819-121-12-199412150-00009

7. Cauwenbergh D, et al. Malfunctioning of the autonomic nervous system in patients with chronic fatigue syndrome: A systematic literature review. European Journal of Clinical Investigation. 2014;44(5): 516-526.  doi:10.1111/eci.12256

8. VanElzakker MB. Chronic fatigue syndrome from vagus nerve infection: a psychoneuroimmunological hypothesis. Med Hypotheses (2013) 81:414–23. doi: 10.1016/j.mehy.2013.05.034

9. Holden S, et al. A systematic review of mitochondrial abnormalities in myalgic encephalomyelitis/chronic fatigue syndrome/systemic exertion intolerance . J Transl Med. 2020;18(1):290.  doi:10.1186/s12967-020-02452-3

10. Hives L, et al. Can physical assessment techniques aid diagnosis in people with chronic fatigue syndrome/myalgic encephalomyelitis? A diagnostic accuracy study. BMJ Open. 2017;7(11):e017521. doi:10.1136/bmjopen-2017-017521

11. Khanna A. et al. (2020) The effects of oral administration of curcumin–galactomannan complex on brain waves are consistent with brain penetration: A randomized, double-blinded, placebo-controlled pilot study. Nutritional Neuroscience. 2020. DOI: 10.1080/1028415X.2020.1853410