Herpes of type 6 - what kind of virus is it and how is it treated?

Many of us the term "herpes" is associated with a rash on the lips and does not attach much importance to it. However, the family of these viruses is quite numerous and insidious. To date, scientists have identified about a hundred types of herpes, parasitic in living organisms. To the person "has got" eight of them, including herpes of 6 type. This virus is present for life in 9 out of 10 people on our planet, but manifests itself mainly in children.

The family of human herpes viruses

All eight herpes viruses are unusually similar in appearance. Sometimes even under a microscope they are difficult to distinguish. Separate them into separate groups is possible only by reaction to certain antigens of their virion proteins, according to the so-called antigenic properties of proteins, and also by the degree of homology (similarity) of their DNA. Some researchers distinguish groups of herpes viruses by the presence or absence of a large envelope. However, this method is not absolutely accurate. The human herpesvirus type 6, in addition, has 2 subtypes, A and B. Since their DNA is 95% similar, they were previously identified as species of the same type, but in 2012 they were isolated into separate species. In addition to 5% dissimilarity in DNA, they also have other differences, in particular, clinical manifestations. However, in laboratories it is impossible to identify them unambiguously.

Type A

To date, it is known that type 6 A herpes is considered to be more neurovirulent, that is, it is more often manifested in those who have diseases of nerve fibers, for example, multiple sclerosis. This ailment is absolutely not related to the age of a person. It occurs with equal frequency in the elderly and in the young. There are cases of detection of multiple sclerosis, even in infants. One of the causes of the disease is called infection with the herpes virus 6A of the nerve tissue of the brain and spinal cord. However, there are other reasons not related to herpes. Clinical manifestations of the disease depend on the site of infection, the stage of the disease and many other factors. In addition, it is believed that the herpes virus 6A is more common in people with HIV. In the laboratory, it was found that in the bodies of macaques, it dramatically increases the development of the AIDS disease. HIV viruses can not enter healthy cells until they have been infected with herpes simplex virus type 6A and have not prepared conditions for them. This feature is adopted by scientists developing methods of treating AIDS.

Type B

Herpes of type 6 B has been studied more widely. According to the results of numerous studies it is established that he is the cause of such a disease, as a child's roseola. It is also called the sixth disease, pseudo-red or exanthema. This ailment is found exclusively in children, and most often in infants up to the age of two. In adults, the body produces immunity to viruses. In the human body, the viruses begin to react with immune factors, and having got into the skin with blood, damage the tissues. The main symptom of the disease is high fever without any symptoms of a cold. At some children it reaches a mark of 40 degrees and above. Sometimes the patient has an increase in lymph nodes. On the 3rd or 4th day on the back, abdomen and chest appears a rash of red or pink, pale with pressure. Within a short time, the rash spreads to the rest of the body. There is no itching and pain, the temperature drops. After a day, less often after a couple of hours the rash passes without leaving any traces.

Herpes Type 6 in adults

Most often, infection with the herpes simplex virus 6B occurs in childhood. In adults, it is present in an inactive state, but under certain conditions its activity may resume. In particular, after organ transplantation, complications in the form of encephalitis or pneumonitis may occur in a number of patients. Encephalitis is an inflammation of brain areas. Pneumonitis - the defeat of the walls of the alveoli in the lungs, which makes breathing more difficult. Some researchers associate with the virus 6B bone marrow depression, leading to shortness of breath, anemia and more serious consequences. In addition, believe that this virus is responsible for the emergence of chronic fatigue, manifested in frustration, apathy, oppression. Herpes of type 6 is associated with hepatitis, with high sensitivity to antibiotics, with cancerous tumors and many others. However, all this has not yet been fully proved.

Mechanism of action of the virus

The herpes simplex virus type 6 has a dense membrane with receptors. The main component for them - a protein CD46, located on the surface of almost all cells. Therefore, the virus so quickly and so easily "settles down" in the body. Once in the human body, it tries to penetrate into the cells of CD4 +, which are differentiated into T-lymphocytes. The latter are able to suppress the immune response. Viruses, using this property, induce the phenotype of T-lymphocytes and bind to the CD46 protein. Since this protein works in all cells except red blood cells, it is easy to imagine the possibilities of this herpes virus in our body. It was first discovered in 1986 in adult patients with HIV. After a couple of years, it was also allocated to infants with roseola. After a series of studies, the herpesvirus of the 6th type was found in people on all continents in almost every country.

Ways of infection

Because type 6 herpes is present in the vast majority of the world's population, it is very easy for non-infected to get it. Most often, this occurs in infancy (from about the 3rd month of life), when the mother's antibodies stop working in the body. A small percentage of children are infected at birth, if the mother of the newborn has picked up this virus in the last months of pregnancy. If the child's parents have herpes, they can infect the baby with direct contact with him. It is known that herpes 6 is present in saliva. Therefore, the easiest way of infection is airborne. You can infect the baby by kissing him or talking to him, bending over his face. Transmission of the virus with breast milk is not possible.

In addition, herpes 6 can be transmitted from a sick person to a healthy person directly with blood. There are cases when infection occurred by injections or when examining the patient with non-sterile instruments.

Diagnosis of the virus

Unfortunately, with a primary infection, it is difficult to detect and accurately recognize the virus of this group. It is even more difficult to identify it during the inactive stage. Determine it by laboratory. There are several methods of determination, depending on the manifestation of the infection. They all boil down to immunological, biochemical and microbiological research.

For example, they are used for myocarditis, which can lead to death. It has been established that it is also caused by the type 6 herpes virus. Symptoms are absent, unlike myocarditis caused by other causes. With this disease, the virus is identified in a biopsy taken from the heart muscle, or in the blood. If questionable results, additional studies are carried out. In pneumonitis, the virus is detected in sputum and serum, and the evidence for its presence may be chest x-ray data. In hepatitis caused by the virus, liver and serum biopsy samples are analyzed . With various tumors and increased lymph nodes, special monitoring and serological tests are performed, as well as blood PCR. This test is widely used in the reactivation of the virus and its inactive form.

Treatment

Completely get rid of the herpes virus of any kind is impossible. The same can be said about herpes of type 6. Treatment in this case consists in preventing the occurrence of relapses and maintaining the virus in an inactive state. The course and methods of treatment depend on the clinical manifestations of the disease. If it is a baby roseola, then special antiviral drugs are not prescribed. If a child has a strong fever, he is given antipyretic drugs such as ibuprofen or paracetamol and a copious drink. Children with depressed immunity are sometimes prescribed "Foscarnet" or "Acyclovir." The latter drug is currently considered not fully effective, so it began to replace "Ganciclovir". A very big disadvantage of baby roseola is that it is often confused with ordinary rubella and prescribed the appropriate drugs, although they are absolutely not needed.

Prevention

As you can see, the herpes virus is quite unpleasant. However, there is one positive point - the human body is able to develop immunity against it. Antibodies to this virus are produced during the first few days after infection. In the future, their number varies, but they are present in the body all the time. They are able to restrain herpes type 6. Symptoms of reactivation of the virus are manifested when a person has problems with the immune system or the body weakens other diseases. Therefore, the main preventive tool is all-round strengthening of immunity. This is the physical load, and the right way of life, and rational nutrition, and vitamin complexes. Another important point of prevention is personal hygiene.