Bipolar and depression are two psychiatric conditions that go hand in hand. People with bipolar disorder tend to have cyclic episodes of depression followed by periods of mania or hypomania. As of late, scientists have found presence of human herpesvirus of type HHV-6 in the neurons of people who had bipolar and depression. It is believed that HHV-6 virus may be responsible for a range of psychiatric and neurological conditions. According to the National Institute of Health approximately 4% of people in the United States have had at least one symptom of bipolar disorder at some point in their lives.[1, 2, 3]
Similarly it is estimated that about 6% of the general population in the United States experience at least one episode of depression at some point or the other. The root cause of both bipolar and depression is not known but what is known is that both genetic and environmental factors play a vital role in the development of both of these disabling conditions. A recent study on the link of genes to psychiatric conditions stated that faulty genes were responsible for at least 80% of cases of schizophrenia.[1, 2, 3]
A latest research published in Frontiers of Microbiology has made a mention of the role of viruses in the development of various psychiatric conditions. A team of international scientists from the Department of Microbiology at University of Wurzburg, Germany, found out that a section of the brain of people who had bipolar and depression was infected with the human herpesvirus of the type HHV-6. The virus was detected in the Purkinje cells. These cells are located in the cerebellum and are responsible for movement, balance, and posture.[1, 2, 3]
Some studies also mention that these neurons are responsible for language, cognition, and mood [1, 2, 3]. The article below goes further into this finding about whether herpesvirus can actually cause bipolar and depression.
Can Herpesvirus Cause Bipolar And Depression?
To further establish this link, the scientists began their research with the hypothesis that HHV indeed was responsible for development of various psychiatric conditions. They then analyzed data from brain biopsies from the Stanley Medical Center in Maryland. On close analysis, it was pretty clear that the Purkinje cells of these people were infected by the HHV-6 virus, especially in brain biopsies of people who lived with a known diagnosis of bipolar disorder and major depression.
It is well known that certain inherited factors play a major role in the development of certain psychiatric conditions, especially bipolar disorder, major depression, and schizophrenia. However what is new is that environmental factors like viruses also have the potency to invade the brain and increase the risk of people developing psychiatric conditions. This is because of the inflammation in the brain that these viruses especially the herpesvirus or HHV-6 causes various psychiatric conditions.
It is believed that these viruses impact neurodevelopment and the overall immune system at vital developmental stages of life. The study clearly showed that HHV-6 can infect the brain and cause mood disorders and cognitive dysfunction. The researchers have also proved wrong the ancient belief that latent viruses in the body are completely harmless and not a threat to the tissues and other vital organs of the body.
They also make mention of the ever growing evidence of HHV causing other neurological conditions as well. There have been studies that have shown a close link between HHV and increased risk of Alzheimer disease. This was also proved with brain biopsies of people who lived with this disease.
The researchers are now planning to investigate as to how the HHV virus damages the Purkinje cells and increases the risk for a person developing psychiatric and other cognitive disorders.