Multiple sclerosis (MS), a neurodegenerative inflammatory demyelinating disease of the central nervous system (CNS), is idiopathic, despite its description more than 150 years ago. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an Original Essay Over the years, a long list of viruses have been associated with multiple sclerosis (MS); however, so far no virus has been definitively implicated in the pathogenesis of MS. Many studies in recent years have used a variety of methods to detect the possible correlation between HHV and MS. Some human herpesviruses (HHV) have been correlated with the development of MS because they have a latent and ubiquitous neurotroph. Human herpesvirus 6 (HHV6) is a very likely virus because it is highly neurotropic, characterized by latency and periodic reactivation, and the same factors that associate virus reactivation such as stress have also been associated with exacerbation of MS, and is ubiquitous Primary infection usually occurs during the first two years of life. Studies have reported the presence of viral DNA in the brain and cerebrospinal fluid of MS patients and controls support that HHV-6 possesses strong neurotropism. Other studies report higher levels of viral mRNA in MS brains compared to control brains, especially in demyelinated plaques. Not only have central nervous system studies established an association between HHV-6 and MS. Other studies focus on early observations of HHV-6 in serum associated with detection of immune response to the virus in MS patients with clinically active disease. A study conducted on the Iranian population found higher levels of HHV-6 IgM and IgG in MS patients compared to controls, 78.2% of MS patients were positive for HHV-6-specific IgG antibodies compared to 76, 4% of healthy people. The frequency of HHV-6-specific IgM in the normal population was 6.5% compared to 34.6% in MS patients. HHV-6 DNA was detected in the serum of 60.2% of MS patients and only 14.6% of healthy patients. Regarding HHV-6 subtypes, one study detected the prevalence of the virus in the serum of relapsing and remitting MS patients and healthy blood donors and demonstrated that exclusively type A is DNA positive in MS patients both relapsing and remitting. Furthermore, studies on the mechanisms of demyelination and oligodendrocyte damage have strengthened the idea that viruses can lead to MS. One such mechanism is molecular mimicry between a pathogen and a self molecule that leads to the generation of an immune response that is cross-reactive between both the pathogen and the self. There is a segment of identical amino acids between the U24 protein of HHV-6 and the human myelin basic protein. A recent American study focused on the role of the HHV-6 U94 protein in interrupting the migration of human oligodendrocyte progenitors. Please note: this is just an example. Get a custom paper from our expert writers now. Get a Custom Essay To the best of our knowledge, there are no previous studies on the prevalence of this virus in Iraq, only two recent studies. One of them was conducted on the association of HHV-6 with some hematological malignancies, which showed that the rate of occurrence of this virus using the PCR technique was 4.6% in patients, compared to 0% in control, and the rate of occurrence of this virus using the IFA test was 74.3% in patients, compared to control 25.7%. The other study showed an active increase in viral load in 16.3% of renal transplant recipients, all of whom were symptomatic and 75% of them.