Today, few people are not familiar with the words "herpes virus", "herpetic infection" or "viral fever". And no wonder. After all, according to medical statistics, up to 90% of the world's inhabitants are infected with one or another serotype of herpesvirus. Herpetic infections in children and adults are acute infectious diseases caused by a whole group of pathogens, manifested by a different clinical picture and having a variety of consequences for our body.
So different, but all bad
Herpesviruses (from the Greek word herpes - creeping) are very widespread in nature. Today, microbiologists have classified about 100 viruses of this group that parasitize in organisms of various taxonomic groups (from bacteria, fish to mammals).
In humans, 8 types of antigens have been identified that cause differentetiology and manifestations of herpetic infections. But all representatives of these pathogens are characterized by high contagiousness (infectiousness), the presence of a latent (latent period) form, leading to a lifelong virus carrier, and a rather good ability to maintain virulence in the environment. With normal indicators, they are viable for a day, on motets and various metal handles - up to 2 hours, on plastic and wood - about 3 hours. They tolerate even high frosts well, and are inactivated within half an hour at temperatures above 50 ° C.
Human herpes viruses 1-5
These pathogens belong to the Herpesviridae family, which includes three subfamilies - alpha, beta and gamma herpesviruses. Today, 8 clinically significant human viruses are isolated, 5 of which are made in the analysis of TORCH infections (TO - toxoplasma, R - rubella (rubella), C - cytomegalovirus, H - herpes). The most common herpes simplex viruses 1 and 2. It is they who are talking about the presence of antibodies to these types of herpesviruses in almost 90% of the population. They make us virus carriers in childhood, and it is very difficult not to get infected with them:
- Herpes simplex virus type 1 (HSV-1) – labial form. The causative agent is Herpes labialis. The face, lips, mucous membranes of the mouth and nose, rarely the cheeks are affected. The most common symptoms of this type of herpes infection are the so-called fever on the edge of the lips. Although the infection spreads throughout the body, it manifests itself inthe appearance of bubbles in the nasolabial triangle. Relapses appear with a frequency of about 3 times a year.
- HSV-2. This is genital herpes. According to statistics, 50% of the infection in this localization is caused by herpes simplex viruses type 1. The routes of infection are more often oral and sexual. At the same time, relapses of herpes infection in the first type occur much less frequently than in the genital one (once every two to three months, or even more often). The duration of the active phase is longer, and the affected area is larger. This is a serious disease that is increasing in its prevalence among the population (up to 24% of those infected).
- HSV-3. The causative agent Herpes Zoster causes the disease shingles or viral chickenpox. The peculiarity of this infection is the defeat of persons in the age category of 35-45 years and older. This is a polytropic virus, the affected areas are mucous membranes, feet and palms, scalp, torso. At the same time, the zones of appearance of bubbles with liquid are huge in area.
- HSV-4. The causative agent Epstein-Barr virus causes the disease infectious mononucleosis - an acute viral infection that affects the lymph nodes, the back of the oropharynx, liver and spleen in the most severe cases. Other names for this disease are monocytic tonsillitis, benign lymphoblastosis.
- Cytomegalovirus (Human betaherpesvirus 5) is the fifth type. One of the viruses that occurs with low immune status and is very dangerous in case of intrauterine infection. In addition, this type of herpes virus infects the internal organs (heart, lungs, kidneys).
Diagnosis: herpetictype 6-8 infection
These are types of herpesviruses that do not yet have enough clinical evidence and are not as common in the human population.
- HSV-6 can be of two variants: 6A - viral proliferative diseases associated with unnatural cell growth (various tumors, lymphomas, lymphosarcomas), 6B - causes sudden exanthema, multiple granular rash. There is evidence of the involvement of this type in the development of hepatitis with an acute course and even death.
- HSV-7 causes chronic fatigue syndrome accompanied by paroxysmal tremors.
- HSV-8 is a specific virus that causes the severe illness of Kaposi's sarcoma in AIDS patients.
According to the World He alth Organization, mortality due to herpes infections is in second place (15.8%), behind hepatitis viruses (36%). And by the age of 18, about 90% of urban residents become carriers of one or even several herpesvirus serotypes.
The structure of the virion
Structurally mature particles (virions) of herpes are quite large - up to 200 nanometers in diameter. Their hereditary material is represented by a double-stranded DNA molecule. In addition to the protein shell, the virion has an outer supercapsid - the outer shell, which includes lipids and glycoproteins. The core (nucleocapsid) consists of 162 capsomeres and has the shape of a polyhedral cube. The surface is covered with protein spikes that provide attachment of the virion tomembranes of the host cell and facilitate the penetration of viral DNA inside.
After that, the virion loses its shell, its nucleic acids are integrated into the host's, and the replication process starts. The formation of young virions and their shells is due to the resources of the host cell. As they accumulate, they break the cell membrane and enter the intercellular space in search of new victims. In the dormant stage, the virus remains in the nerve ganglia and does not manifest itself in any way.
Classification of herpetic infection
Due to the diversity of pathogens, there is no universal classification of these infections. But depending on the fundamental criteria, the following types of herpes infections are distinguished:
- Criterion of clinical manifestations: typical forms of infection (with rash) and atypical forms (without rash or with minor).
- Depending on the severity of the course: mild, moderate and severe herpetic infections.
- According to the localization of the inflammatory process: genital or epithelial, herpetic lesions of the nervous system, eyes, mouth, and so on.
- According to the form of the course of the disease: acute primary and chronic recurrent infections.
It is precisely in connection with such a complex classification of this type of infection that a wide range of specialists are involved in its treatment and diagnosis - from venereologists to neuropathologists, and even oncologists.
How a pathogen enters the body
The main reservoir of the virus is an infected person. All types of pathogens of herpes infection in children and adults enter the body in three ways:
- Percutate (contact household).
- Aerosol (airborne).
- Vertical (the fetus receives the infection from the mother).
The ways of infection are different, and it is often impossible to draw a line between them. And yet it is considered the most common contact-household route of infection. The pathogen is transmitted through contaminated objects (dishes, toys, cosmetics, and so on). Kissing is also possible. In this case, often after it there is no acute phase, and the disease proceeds latently. Under certain circumstances, about which a little later, the virus breaks out and reveals itself.
When genital herpes infection occurs through sexual intercourse and oral sex. This type of herpes is included in a special WHO research program, which indicates its pathogenicity. In European countries, herpes is the second most common sexually transmitted disease, behind only trichomoniasis.
In case of aerosol infection, the infection proceeds according to the type of acute respiratory infections. So children are more likely to become infected, but in adults, a herpes infection can also occur in this way. With primary infection, an acute form of the course of the disease occurs with severe symptoms of a respiratory disease, which disappears within a week.
Vertical transmission and pregnancy
Fetus can get infection from mother in three ways:
- Most common infectionsfetus occurs during the passage of the birth canal during childbirth. But only if the mother has severe symptoms of genital herpes. The risk of infection in this case is about 40%.
- Ascending infection through the cervical canal can enter the uterus and infect the fetus there. Less than 5% chance of fetal infection.
- Transplacental transmission - infection of the fetus through the placenta at different stages of pregnancy. This is possible provided that the mother suffers from various forms of herpes.
To begin with, it should be noted that the presence of antibodies in the mother's blood for primary herpes viruses is not a contraindication to pregnancy and natural childbirth. Today, all pregnant women are tested for TORCH infection, and if antibodies are present, this is very good. This means that the mother will pass them on to the fetus and partially protect it from primary infection.
Recurrent herpes in a pregnant woman brings discomfort to the mother rather than a danger to the child. Now, if antibodies are not found in the mother's blood, this means that during pregnancy, a primary infection of the mother may occur, which is very dangerous for the child.
Intrauterine infection of the fetus is the most severe infection in terms of consequences. Infection of the fetus in the first trimester of pregnancy leads to its death and miscarriage, in the second and third trimester the fetus may become disabled and CNS lesions.
Stages of disease progression
As already mentioned, the development and symptoms of the disease are different in the caseprimary and secondary infection with herpes simplex viruses. Most often, the primary infection is successfully suppressed by the immune system and is asymptomatic. After that, the virus hides in nerve cells and there it goes into a dormant state. Many people will never get it.
But in some cases we are dealing with a true manifestation of a primary herpes infection with all external symptoms. After treatment of the disease, the virus again lies dormant in the nerve endings. The reactivation of the virus and the transition of the infection to a recurrent form (periodic onset of symptoms) occurs when there are special conditions in the body.
In a he althy body, the immune system recognizes and destroys up to 3 thousand cells affected by various pathogens every second. Decreased immunity status is the main cause of herpes recurrence, and this is caused by stress, overheating or hypothermia, change of time zones and climatic conditions (from minus 25 to plus 25 degrees during flights). The appearance of relapses is facilitated by the excessive use of alcohol, antibiotics and hormonal drugs that affect the immune system.
Separately it is necessary to note such factors as immunopathological conditions - chronic diseases, oncology, consequences of radiation exposure, immunodeficiencies.
At the same time, relapses and their symptoms may be mild and blurred and not cause much discomfort to the wearer.
TORCH-screening and other research methods
Diagnosisherpetic infections have recently become possible in the laboratory, as they are quite easy to differentiate by clinical symptoms. In the absence of visible symptoms, laboratory tests are performed. Modern methods for studying these infections have several methods in their arsenal, where the research material is scrapings of the skin and mucous membranes, biological fluids (saliva, urine, blood).
Virological methods use cell cultures and polymerase chain reactions. The paired sera and color test method is a fairly common serological test. Rapid TORCH screening methods have been developed by WHO to analyze diseases that are dangerous to the fetus. But this analysis can be done not only for pregnant women.
Herpes simplex is not an easy cure at all
It has long been known that in adults, a herpes infection is found in 90%. But only about 20% have clinical manifestations. Most of us become infected between the ages of 3 and 5 and remain carriers for life. It is impossible to get rid of the virus, but it is possible to alleviate its course or reduce the likelihood of manifestations. That is why the treatment of herpes infection is reduced to the prevention of relapses and the relief of initial symptoms. Preventive methods include measures to strengthen the overall immunity of the body and reduce factors that affect the status of the immune system.
At the first symptoms of infection, it is important to quickly apply emergency measures. enough for breakoutstopical application of antiviral drugs in the form of ointments, with more serious manifestations and frequent relapses, special preparations are used to treat herpes infection (Acyclovir, Valaciclavir, Farmciclovir, Tromantadine). Treatment also includes the use of special forms of interferon and the use of drugs that stimulate the production of the body's own interferons (for example, Cycloferon).
But the complexity of treatment is that all effective drugs are quite expensive, and the treatment is long and carried out according to a certain scheme, taking into account the specifics of the infection, the state of immunity and the patient's concomitant diseases. That is why self-medication is not an option in this situation. Consultation with a competent specialist, high-quality examination is the key to successful "taming" of the virus and taking it under control. Parents need to know that frequent "colds" on their children's lips can turn into a serious problem in the future, and do not neglect seeking help from specialists.
