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Viruses that May Trigger Hashimoto’s

Viruses that May Trigger Hashimoto's

Hashimoto’s thyroiditis is a condition influenced by several factors. One of the many being the presence of a virus. Research shows that a number of common viruses influence thyroid and immune function, which may encourage the development and continuation of Hashimoto’s.

To better understand and treat Hashimoto’s we must be familiar with the condition itself, be familiar with the relevant mechanisms of viruses, and identify common viruses that promote thyroid malfunction.

What is Hashimoto’s Thyroiditis?

Hashimoto’s thyroiditis is an autoimmune thyroid disorder wherein the immune system mistakenly attacks and destroys healthy thyroid tissue. The result is a significant decline in thyroid function and an ever-increasing state of hypothyroidism. 

Hashimoto’s is rarely seen on its own and may be worsened by immune-related stress or malfunction. Therefore, the presence of other chronic illnesses or infections often contribute to the severity of Hashimoto’s.

Hashimoto’s does not develop on its own. Several factors such as stress, certain medications, toxin exposure, and food sensitivities encourage Hashimoto’s. However, these elements only set the stage for autoimmune dysfunction. For Hashimoto’s to occur, an autoimmune trigger must be present. Recently, it was found that common viruses may act as a trigger for Hashimoto’s.

How Viruses Encourage Hashimoto’s

Multiple mechanisms of immune function may be disrupted by viruses. Molecular mimicry, the bystander effect, and the encouragement of leaky gut are just some of the ways in which viruses may disrupt immune function and trigger Hashimoto’s.

Molecular Mimicry

If a virus contains similar proteins to cells or tissues in the body, the immune system may mistakenly target healthy structures in the body. There are several infectious pathogens that have molecular structures that mimic thyroid tissue. As such, antibodies released to eliminate a threat may mistakenly target thyroid tissue and contribute to the development of Hashimoto’s.

Inducing Leaky Gut

Viral infections may encourage increased immune activity in the gut, which can result in intestinal permeability or leaky gut. Leaky gut is a key component of autoimmune malfunction and greatly increases the risk of Hashimoto’s. 

The Bystander Effect

In some cases, viral infections may establish themselves in specific tissues. The immune system responds by attacking the afflicted tissue to destroy the invasive pathogens. If thyroid tissue becomes infected, the immune system may attack the gland to eliminate the infection. This action can cause irreparable damage to the thyroid gland and trigger Hashimoto’s.

What Viruses do I Need to Watch Out For?

There are several viruses that can trigger Hashimoto’s. These include Influenza, Coxsackie B, Parvovirus B-19, Enterovirus, Rubella, HTLV-1, Mumps, and HIV. However, perhaps the most common viral triggers of Hashimoto’s are Herpes Simplex 1 and 2, Epstein-Barr, Cytomegalovirus, and Hepatitis C. 

Herpes Simplex Virus 1 and 2

There are two common strains of the Herpes Simplex Virus; HSV 1 and HSV 2. 

  • HSV 1 may be asymptomatic or produce symptoms including cold sores, skin lesions on the genitals and elsewhere, and encephalitis. 
  • HSV 2, also known as genital herpes, is a sexually transmitted disease that affects the genitals, buttocks or anus, and mouth. 

HSV may remain dormant or inactive for extended periods. In this state it poses little to no threat. However, studies suggest that poor thyroid hormone values, often seen among those with hypothyroidism, may reactivate the virus. This can aggravate the immune system thereby encouraging autoimmune malfunction and subsequent Hashimoto’s.


Epstein-Barr virus (EBV) is a condition belonging to the herpes family of viruses. It is exceptionally common with studies estimating that up to 95 percent of Americans will contract it by the age of 40.

EBV may produce symptoms such as sore throat, swollen lymph nodes, and severe fatigue. It may also be asymptomatic for long periods only to reactivate at some later time. 

Perhaps the most concerning aspect of Epstein-Barr is that it may contribute to chronic illness and autoimmune conditions like Hashimoto’s.

T-cells are one of the immune system’s best tools for eliminating pathogens. When T-cells encounter cells containing EBV, they release inflammatory cytokines to destroy the derelict cells. Unfortunately, if EBV is established in the thyroid, cytokines may mistakenly attack healthy thyroid cells resulting in Hashimoto’s and a decline in thyroid function.


The Center for Disease Control estimate that more than 50 percent of adults over the age of 40 will contract Cytomegalovirus (CMV).

CMV, also referred to as herpes virus 5, is most often asymptomatic but may cause fever, swollen glands, sore throat, and fatigue. Patients who are immunocompromised may experience more severe infection that results in dysfunction of various organs including the lungs, brain, and liver.

Studies show that CMV often precedes autoimmune issues including Hashimoto’s. Similar to Epstein-Barr, CMV causes autoimmune malfunction via the bystander effect. If CMV establishes itself in the thyroid gland, the immune system may destroy thyroid tissue in an attempt to eliminate the virus thereby triggering Hashimoto’s.

Hepatitis C

Reports estimate that three million Americans have contracted the liver-attacking virus Hepatitis C. Nearly 75 percent of individuals with acute Hepatitis C are expected to develop a chronic illness. Unfortunately, a large percentage of those infected are unaware of their condition and increased risk of disease because most cases of Hepatitis C are asymptomatic.

Studies show that autoimmune thyroid disease has a higher occurrence rate among chronic, untreated Hepatitis C patients. Interestingly, cases of autoimmune thyroid disease are also elevated in treated cases of Hepatitis C. This is because the medication used to treat Hepatitis C, interferon, is a known trigger for Hashimoto’s.

Although the exact method is not fully understood, studies show that Hepatitis C encourages Hashimoto’s by traversing the bloodstream and infecting the thyroid gland. This instigates an autoimmune response against the thyroid gland thereby triggering Hashimoto’s.

Testing and Treating Viral Triggers of Autoimmune Malfunction

If a virus is triggering erroneous autoimmune activity, thorough testing and treatment are essential.

Depending on the suspected illness various testing methods may be employed. For the viruses discussed above, patients will likely undergo a variety of blood tests that assess for the presence of specific antibodies, pathogens, or biomarkers. In some cases, a biopsy may be also be required.

Fortunately, each of the above triggers of Hashimoto’s are treatable through standard practice. After completely eliminating any and all existing viruses, autoimmune disorders like Hashimoto’s should become much easier to resolve.

Eliminate Hashimoto’s by Treating Triggers

If you are suffering from autoimmune thyroid dysfunction, be sure to consider the possible influence of an underlying virus. Thoroughly testing for and treating common viruses such as Herpes, Epstein-Barr, Cytomegalovirus, and Hepatitis C may be the key to resolving a persistent case of Hashimoto’s.


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