Vagus nerve infection hypothesis

The Vagus Nerve Infection Hypothesis (VNIH) proposes that the symptoms of Chronic Fatigue Syndrome are caused by an infection of the vagus nerve.

In 2013, Michael VanElzakker, then a postdoctoral researcher at Harvard Medical School, published the hypothesis.

The vagus nerve, also called the tenth cranial nerve, starts in the brain and runs down the trunk of the body, with branches that innervate the major organs. It is responsible for the sickness response, an involuntary response characterized by fatigue, fever, myalgia, depression, and other symptoms that are often observed in patients with CFS.

Theory

As explained by Dr. VanElzakker: "The vagus nerve infection hypothesis of CFS contends that CFS symptoms are a pathologically exaggerated version of normal sickness behavior that can occur when sensory vagal ganglia [structures containing a number of nerve cell bodies]or paraganglia [non-nerve cells that surround nerves] are themselves infected with any virus or bacteria.... [The] glial cells [clells that support and protection neurons] can bombard the sensory vagus nerve with proinflammatory cytokines and other neuroexcitatory substances, initiating an exaggerated and intractable sickness behavior signal. According to this hypothesis, any pathogenic infection of the vagus nerve can cause CFS, which resolves the ongoing controversy about finding a single pathogen." The neuroimmune cells whose job is to protect the nerve, such as mast casts and glial cells, can sense an infectious agent and become activated, in turn signaling the vagus nerve to tell the brain there is an infection present, causing a systemic reaction.

VanElzakker believes that any infectious agent with an affinity for nerve tissues can cause a vagus nerve infection, including HHV-6, Epstein-Barr virus, Varicella zoster virus, Chickenpox, certain kinds of enteroviruses and even Borrelia, the bacterium that causes Lyme disease. He thinks this could explain why no single infective agent has been isolated as the cause of CFS, even though all of these agents have been associated with disease.

Notable studies

• 2016: Autonomic correlations with MRI are abnormal in the brainstem vasomotor centre in Chronic Fatigue Syndrome
• 2013, Chronic fatigue syndrome from vagus nerve infection: a psychoneuroimmunological hypothesis.

Learn more

• 2016: Vagus Nerve Infection Hypothesis and the Driscoll Theory
• 2013, Article about Michael VanElzakker and his theory on the HHV-6 Foundation Website
• Michael VanElzakker quotes Louis Pasteur in reference to the Vagus Nerve Infection Hypothesis: "The germ is nothing; the terrain is everything."

See also

• Vagus nerve stimulation
• Twitter #VNIH

References

<references>

ganglion A ganglion is a group of neuron cell bodies in the peripheral nervous system. Plural: ganglia / ganglions

cytokine any class of immunoregulatory proteins secreted by cells, especially immune cells. Cytokines are small proteins important in cell signaling that modulate the immune system. (Learn more: me-pedia.org)