Chronic Fatigue: We’re Still Not Sure What Causes It

Friday Feb 15 | BY |
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Chronic Fatigue

Could you be constantly tired because of a virus?

I had only been in clinical practice for about a year when Incline Village, Nevada became ground zero for chronic fatigue syndrome (CFS). Daniel Peterson and Paul Cheney, both private practice physicians at Incline Village, became pioneers in a shadow epidemic that started with an outbreak of a strange illness in 1984 in the Lake Tahoe region.

Within three years, the two physicians found the illness in 259 patients in the area. Because symptoms were similar to mononucleosis, Peterson and Cheney believed Epstein Barr Virus (EBV) caused it. After a few years, however their theory was proven wrong.

A Real Illness with Many Names

During this same time period, patients started to arrive at my clinic in San Diego with similar complaints: debilitating fatigue, brain fog, and weakness without an infection or obvious underlying illness. What was first suspected as a local epidemic very quickly showed up in other parts of the United States and Europe, mostly in Britain.

Doctors were baffled. In 1987, the New York Times published a long article about the new illness. People were getting sicker without a reason.

More and more cases of CFS, also referred to as “chronic fatigue immune deficiency syndrome (CFIDS)” or “myalgic encephalomyelitis (ME)” in England, turned up. Patients sought treatments that didn’t exist for an illness that wasn’t recognized as a disease. Conventional MDs brushed patients off as hypochondriacs. It was not until 1994 that the CDC recognized CFS as a real condition, giving it an ICD diagnostic code under the “Fukuda definition.”

A Real Diagnosis

Developed by a research team lead by Keiji Fukuda, M.D., M.P.H., an influenza epidemic specialist, for the first time CFS suffers had a real diagnosis to legitimize their condition.

The clinical definition of persisting or relapsing debilitating fatigue contained eight points that included the concurrent occurrence of four or more of the following symptoms:

  • 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;
  • refreshing sleep; and
  • post-exertional malaise lasting more than 24 hours.

The Disease Hits Me

In 1996, after completing ethnobotanical fieldwork at a biological research station in the upper Amazon rainforest, I was taken by a malaria-like illness. After months of intensive diagnostics, my doctors declared that I didn’t have malaria, but they had no idea what
caused my massive fatigues and weakness, severe joint pain, and inability to think clearly.

I was so exhausted that it took a major effort to even pick up a pencil! I had all eight of the CDC criteria symptoms, and every one was severe. In fact, I was considerably sicker and weaker then most of my CFS patients.

Frustrated with conventional medicine, I eventually treated myself and gradually recovered. But it took years. My experience with CFS inspired me to delve deeper into viral disease, which resulted in the publication of my first book, Viral Immunity, in 2000.

Anti-Viral Drugs Seem to Work

For more than ten years, viral infection as a cause for CFS was ignored. Most of the clinical focus shifted to adrenal fatigue, hormone deficiencies, allergies, and stress-related imbalances.

I wasn’t satisfied with any of the explanations, because they were too easy, not grounded in good clinical science, and the biological understanding of complex immune interrelationship was still in its infancy. And, when patients were treated with therapies for these causes, they still didn’t get better. When treated with common anti-viral drugs used for herpes simplex virus, however, most patients felt distinctively better.

From my view, viral and other infections like mycoplasma that were found in laboratory studies of my CFS patients had something to due with the condition. But were they the cause, or only linked to the disease?

The Science Falls Apart

In 2006, scientists announced a provocative finding about a retrovirus called “xenotropic murine leukemia virus-related virus (XMRV).” A handful of retroviruses, like HIV that causes AIDS, were getting a lot of attention. XMRV, closely related to a known virus from mice, was found to be associated with prostate cancer. In 2009, what was to become one the most interesting and bruising scientific debates of the times came to light: XMRV was thought to be the cause of CFS.

At first, results weren’t promising. Retroviruses are notoriously difficult to detect. The immune system doesn’t efficiently make antibodies against them and infections can persist at extremely low levels, but still cause symptoms like those in CFS. The XMRA theory made sense.

Yet the science quickly fell apart. Federal government agencies and European scientists got involved. Repeated failure to detect the virus prompted researchers to consider alternate explanations that effectively ended most worries about the virus.

The Death of a Theory

The debate reached its apex in 2010 when researchers found that XMRV came from a single prostate cancer cell line grown in lab dishes. All of the XMRV lab results isolated from patients came from a single lab-grown cancer cell line.

The implication was that XMRV came from the lab cell lines rather than patients. XMRV detection in CFS patients was an artifact, the product of hard-to-track-down contamination derived from a cell line that had picked up the laboratory virus during experiments with mice.

By 2012, the XMRV hypothesis was scientifically dead and buried. A study that cost taxpayers $2.3-million, funded by the U.S. National Institutes of Health (NIH), found no evidence to support XMRV to chronic fatigue syndrome.

W. Ian Lipkin, a molecular epidemiologist at Columbia University in New York, shepherded the effort. When things get tough in infectious viral disease, Lipkin is the guy they call. Between 2002 and 2010, his lab got 10,000 samples a year and discovered at least 400 new viruses. This scientist knows his stuff. He’s worked on West Nile Virus and a viral infection link to autism. But there were a few wrinkles in the XMRA studies: some people were infected with XMRV, even if it wasn’t associated with CFS.

The Cause May Be More Complicated

Scientists have put the XMRV hypothesis behind them. But, I’m not satisfied. How did a mouse virus get into people in the first place? Has an evolutionary super-virus developed in a lab escaped and gone global? Why do I find clusters of many viruses like EBV, CMV, HHV-6, HSV-2, and other infections like mycoplasma in my CFS patients’ labs? Why do I find deficiencies in their T-Lymphocyte counts? Why don’t they get better?

Like we’ve done for the last 30 years, doctors keep trying different therapies on CFS patients even though scientists haven’t yet nailed down a cause. But, is there one causative pathogen?

The whole saga of XMRV requires questioning the traditional medical paradigm that there is one cause for each disease. Viruses seem to play a role in CFS, but is one virus the specific cause?

In the mean time, I keep looking at the biomarkers in patient lab tests, testing innovative therapies, scouring the scientific literature, and attending the conferences in the hope of finding clues.

Learn More

New York Times

The CDC (Fukuda 1994) Definition for Chronic Fatigue Syndrome

Science Magazine

Discover Magazine: Chasing the Shadow Virus by Hillary Johnson, March 2013

Dr. J. E. Williams


Dr. Williams is a pioneer in integrative and functional medicine, the author of six books, and a practicing clinician with over 100,000 patient visits. His areas of interest include longevity and viral immunity. Formerly from San Diego, he now resides in Sarasota, Florida and practices at the Florida Integrative Medical Center. He teaches at NOVA Southeastern University and Emperor’s College of Oriental Medicine.

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  1. Dr. Williams,
    I believe my son and I both had EBV prior to 1992. He had an immune and bleeding disorder…he developed lymphoma. While he went thru a bone marrow transplant in 1993 they mistakenly gave him CMV positive blood. Our family had been checked for CMV prior to the transplant and were negative. I got very sick after my sons transplant…I was diagnosed with CMV and EBV. I now have brain stem, central nervous system and neuropathy illness. Perhaps the progression of these events sheds some light on the cause of this dreadful illness.

  2. Melissa says:

    Kevin, thank you for including this discussion in your weekly wednesday update. i had a bout of mono that lasted with infections on and off for 3 years; i self medicated with wild oregano oil, thyme oil and other naturopathics, acupuncture & chinese herbs. two years later, i would describe myself as still prone to bouts of dehibilitating fatigue and adrenal exhaustion. A raw food diet really helps; I think alot of the medical ideas of diagnosis and cure are too closed– the fact is your body can and will fall into illness if your temperature periodically or regularly lapses below about 95 degrees or your have pro-longed exposure to environmental or food allergens, including electromagnetic pollution factors, industrail noise, dirty inner city cargo trains, etc. i habitually wear scarves now in all seasons, doused with a few essential oil scents: wintergreen, eucalyptus, juniper, etc. these all help keep lumps and lungs happy and healthy. One factor that people regularly forget is how much a person’s morale suffers as they experienced these bouts of what looks like adult ADD: inability to finish jobs, follow through with goals, remember important dates and appts. … in short, i still have to work at my short term memory function; things that would have taken mere hours to learn are re-forgotten or re-remembered in terms of my state of health. This disease needs to be recognised.

  3. Mary says:

    ME is not another [British] name for CFS. This article both ignores the whole history of research eg Basant Puri, Vance Spence, UK., and the whole history of healing it which has long acknowledged the presence of a virus as not necessarily the cause eg the many nutritional and herbal approaches like the School of Natural Healing, Gerson Therapy, even middle ground Mark Hyman would have provided you with a good explanation of how the situation lends itself to cfs developing, however, if you want ME, then you need to look deeper

  4. Any doctor before 1973 new that what is now called chronic fatigue syndrome was low thyroid and low intake of Iodine. CFS is a made up disease for those that do not understand how the thyroid works. Chronic fatigue is greneralised muscle aches and pains with severe fatigue and susceptible to almost any infection which was a classic discription of Hypothyroid. Doctors today have no idea how to treat or even diagnose low thyroid.

    Do to todays diet high in Bromine, Chlorine and Fluorine which all displace Iodine and the extremly low intake of Iodine there is a chronic Hypothyroid throughout the country. Taking blood tests are not accurate as the Iodine is NOT present yet the TSH or even the Free T4 and Free T3 will show normal. The real test for Iodine is body temperature, do not believe any doctor that says that low temp is normal. With low thyroid you are more susceptible to any virus. People need to take up to 50mg. of Iodine per day for a year to displace all of the Bromine, Fluorine and Chlorine and then the reseptor sites for Iodine on all the cells of the body will contain Iodine.

    Treat the thyroid properly and Chronic Fatigue Syndrome disappears.

    • Deb says:

      This is very interesting information. My mother has been on thyroid meds for many years and I don’t see how it helps her. She is always tired and naps at least twice a day, hardly had the energy to do anything.

      Could you tell me, is there a preferred way to take the 50 mg of iodine?

  5. Deb says:

    Interesting discussion..
    I heard on line, a tape of the person, whose name I can’t remember, who started the vaccine movement, say that sometimes ‘wild viruses’ would end up being a part of the early vaccine treatments. He mentioned cancer being among them. I wonder if this could play a role in CFS? I believe that this was from one of Dr Mercola’s posts.

    Also, what about the virus used to insert genes into genetically modified plants that many of us are consuming unknowingly? Could there be a connection here, also?

    I have struggled with extreme exhaustion for extended periods of time since the early 90’s. Today if I work out at the gym, I may not have the energy to shower after, or do much of anything else, and have to lie down.. Sometimes I am out of it for a couple of days afterward. My joint pain seems to increase with more exercise even though I am careful to only use the machines at the gym that won’t pound my knees like the elliptical, arc and the bike. I also do strength training and plenty of stretching after my workouts. I feel like the’ living dead’.

    Melissa’s posts reminded me that I also had a very bad case of mono which lasted about 6 months, many years ago.
    And Dr. Ben-Joseph’s post reminds me that my normal body temperature runs between 97 and 97.5.

    • Louis Dupont says:

      Dr. Ben-Joseph omitted to mention axillary temperature rather than oral. In hypothyroidism, your blood’s circulation may be radically decreased. Your body shunts blood to vital organs. This will readily show up in decreased armpit (axillary) temperature, not necessarily in oral temperatures. Dr. Broda Barnes wrote about this in JAMA in 1942.
      Body temperatures ranging from 97.0°F (36.1°C) to 97.5°F (36.4°C) would definitely place you as suspect hypothyroid. Refer to Dr. Mark Starr’s excellent book “Hypothyroidism Type 2” for basic guidelines to cure yourself. According to Drs Barnes and Starr, normal axillary temperatures are 36.6 – 36.8°C at wake, reaching 37.0 – 37.5°C throughout the day.

      Peripheral Resistance to Thyroid Hormones caused by blocked thyroid receptors is real, and far more prevelent than you’d think.
      Please refer to the following excerpt from a letter by Dr. Richard L. Garrison @
      “Our research group has given doses far in excess of those given to the Kaplan patient, ranging up to 1350 ?g of liothyroliothyronine (T3) (T4 equivalence 5400 ?g) on multiple occasions without thyrotoxic effects.”

      The average adult thyroid gland will produce ~100 ug of T4 daily, along with ~20 ug T3. 1350 ug T3 would probably be fatal in many people – unless Peripheral Resistance to Thyroid Hormones is present.

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