Exploring the Hidden Threat: Persistent Viral Infection, Viral Reactivation and Its Impact on Health

When we think about viruses, the sheer number of them can be mind boggling; there are an estimated 10 nonillion (that’s 10 followed by 31 zeroes) individual viruses on Earth. To put that into perspective, that is enough to assign one virus to every star in the universe 100 million times over.

Viruses are part of our DNA

Viruses are everywhere, infiltrating nearly every part of our natural world and can infect organisms from every branch of the tree of life, including many types of human cells, making them a powerful and omnipresent force in the biological world. Around 10% of the human genome is actually made up of viral DNA - a lasting legacy of ancient viral infections. This viral DNA mainly comes from retroviruses, a type of virus that has the unique ability to insert its genetic material directly into the DNA of its host. Once embedded, these viral sequences can be passed down through generations, becoming a permanent fixture in our genetic code. Over millions of years, these fragments of viral DNA have become part of what makes us human, a silent reminder of our evolutionary history and the viruses that have shaped it.

Viral infections

Despite the staggering number of viruses only a few hundred are known to be pathogenic to humans. However, those that do pose a threat to us can lead to a wide range of illnesses, ranging from mild colds to more serious disease depending on the type of virus and the state of an individual's immune system. The widespread devastation caused by COVID-19 may be symptomatic of our declining ability to defend ourselves against viruses, a decline likely linked to modern lifestyle factors. As we have explored in previous blogs, these factors may be contributing to increased fragility and immune system maladaptation, leaving us more vulnerable to infectious threats, including viral threats. 

Following the COVID pandemic, many people are now grappling with Long COVID, a condition marked by persistent or new symptoms long after the initial infection has cleared. Researchers are still trying to understand potential cofounding factors for developing persistent viral symptoms. For example, Dr Shoemaker and his team found an association between Long COVID, and individuals exposed to actinobacteria from living in water-damaged buildings. Thus, their research suggests that additional environmental exposures may significantly increase the risk of developing long COVID. Other research has proposed that the presence and reactivation of viral infections such as Epstein-Barr Virus (EBV) and Human Immunodeficiency Virus (HIV) may be significant contributors to Long Covid with suggestions also of deferential effects of various chronic viral coinfections thus leading to distinct symptom patterns.

Viral reactivation.

Viral reactivation is a phenomenon where a dormant virus, previously suppressed by the immune system, becomes active again. While many may be familiar with the initial infections caused by viruses, the concept of reactivation is perhaps less understood and, in many instances less accepted as a cause of disease. However, mounting research indicate that viral reactivation may play a crucial role in various health conditions, including autoimmune diseases, CFS/ME and tick-borne illnesses for example.

What Is Viral Reactivation?

Many viruses, once they infect a person, do not entirely leave the body. Instead, they remain latent, hiding in cells and evading the immune system's surveillance. Herpes viruses such as EBV, HSV, CMV and HHV6, are prime examples. After the initial infection, these viruses can enter a dormant phase, residing within certain cells, notably neurons or immune cells. 

Reactivation occurs when these latent viruses are triggered to start replicating again. This can lead to the reappearance of symptoms or the development of new health issues, depending on the virus and the host's immune status.

Why Does Viral Reactivation Happen?

Several factors can trigger viral reactivation, including: 

1. Immunosuppression: When the immune system is weakened, whether due to illness, stress, medications (such as corticosteroids), or other factors, latent viruses may reactivate. Conditions like HIV, chemotherapy, or organ transplantation often involve compromised immunity, increasing the risk of reactivation. 
2. Stress: Physical or emotional stress can alter immune function, potentially triggering reactivation. Stress hormones like cortisol can suppress certain immune responses, creating an environment where viruses can emerge from latency.
3. Inflammation: Chronic inflammation, whether from infection, autoimmune diseases, or other sources, can lead to viral reactivation. The inflammatory environment may disrupt the host's immune system. 
4. Aging: As the immune system naturally declines with age, known as immunosenescence, the risk of viral reactivation increases. Older adults are more susceptible to conditions like shingles, caused by the reactivation of the varicella-zoster virus (VZV) for example.
   

Consequences of Viral Reactivation

The consequences of viral reactivation can range from mild to severe, depending on the virus and the individual's health: 

1. Recurrence of Symptoms: For viruses like HSV, reactivation often leads to symptoms such as cold sores or genital lesions. For VZV, reactivation may result in shingles, a painful rash that can have lasting effects like postherpetic neuralgia.
2. Chronic Health Conditions: Reactivation can also contribute to the development or exacerbation of chronic conditions. For example, EBV reactivation has been associated with chronic fatigue syndrome (CFS), where individuals experience prolonged and debilitating fatigue.
3. Autoimmune Diseases: Some studies suggest a link between viral reactivation and autoimmune diseases. For instance, EBV has been implicated in multiple sclerosis (MS) and systemic lupus erythematosus (SLE). The hypothesis is that reactivated viruses might trigger an immune response that mistakenly attacks the body's own tissues.
4. Neurological Complications: In some cases, reactivation can lead to serious complications. For example, VZV reactivation can cause encephalitis (inflammation of the brain), particularly in immunocompromised individuals.
   

Viral Reactivation and Autoimmune Disease

The relationship between viral reactivation and autoimmune disease is complex and still under investigation. One theory is molecular mimicry, where viral proteins resemble the body's own proteins, leading the immune system to attack both the virus and the host's tissues. Another possibility is that viral reactivation causes chronic inflammation, which then triggers an autoimmune response. 

As mentioned above, EBV is strongly linked to MS. Some research suggests that the immune system's response to EBV reactivation might contribute to the autoimmune attack on the nervous system seen in MS patients.

Viral Reactivation and Chronic Fatigue Syndrome (CFS)

CFS and Myalgic Encephalomyelitis (ME), are debilitating conditions characterised by severe, unexplained fatigue that doesn’t improve with rest and in the case of ME inflammation may be more apparent. Emotional trauma, excessive and ongoing stress, physical trauma, infections and toxins/biotoxins have all been implicated in CFS/ME. 

EBV reactivation has been particularly associated with CFS. Some patients report an initial bout of infectious mononucleosis (caused by EBV) followed by persistent fatigue and other symptoms. Research is ongoing to determine the impact of these viruses, but it is a fact that many sufferers of CFS/ME seem to carry a higher-than-average viral burden.it is a fact that many sufferers of CFS/ME seem to carry a higher-than-average viral burden.

Testing with Colab Services

Colab Services offers a range of testing options for detecting active or reactivated viruses, which can be crucial in assessing chronic, complex diseases. Paired with Lymphocyte Typing (also known as immunophenotyping), which provides precise identification and measurement of different lymphocyte populations to help uncover abnormalities in the immune system, this can help equip practitioners with the insights they need to design personalised treatment protocols.

Tests – serology:

LMVS-2: EBV, CMV, VZV, CMV – antibodies IFT 

LM002: Lymphocyte Typing plus EBV, CMV, VZV, HSV 1&2, HHV6, PARVO (B19), Chlamydia trach./pneum. – antibodies IFT 

LM001: Lymphocyte typing plus EBV, CMV, VZV, HSV 1&2 – antibodies IFT 

LM6210: Long COVID/Postviral NEURO Panel includes GPC-recep.-AutoAbs,(b1, b2, M2, M3, NMDAR-Ab 

LM6230: Long COVID/Post Viral Panel includes AutoAntibodies, inflammatory markers, essential elements, Leaky Gut 

If you have specific requests please get in touch and we can help you put together a bespoke panel to match your requirements.

Effective Interventions

Micro-immunotherapy, along with targeted lifestyle interventions, can be a powerful approach to supporting specific immune responses and disrupting viral replication. Colab Services is launching an exciting new course on micro-immunotherapy and Lymphocyte Typing this month. If you are interested in learning more or signing up, please contact Helen at [email protected] for details.