In summer and winter, adults and children, low-income and frankly rich - enterovirus infections do not spare anyone. The symptomatology of diseases that are associated with this pathogen has a wide range. The geography of viruses and their diversity is amazing. Let's try to understand the etiology, sources, routes of infection, methods of treatment and clinical recommendations for enterovirus infection.
Relevance of the topic
Data on epidemiological outbreaks recorded in different countries demonstrate the activation of enterovirus infections in the world. The geography of distribution of this group of pathogens is ubiquitous, the clinical manifestations are diverse.
The peculiarity of infections of this kind is associated with the concept of virus carriers. This means that the virus can be in the human body, but manifests itself in special cases - when natural immunity is weakened. In addition, virus carrying contributes to the formation of spores, leading tomass diseases and infection of a large number of non-immune recipients.
Pathogenicity and manifestation
This is a group of infections that are mostly asymptomatic or do not harm a person too much. But there are exceptions to every rule. It is enterovirus infections that are in second place in the frequency of cold-like diseases.
Infection can be extremely dangerous and affect all systems and organs, muscles, mucous membranes. This anthroponosis has two reservoirs:
- a person where the pathogen multiplies and accumulates;
- environment (water, air, food) where virions are able to maintain virulence for a long time.
The main route of transmission of enteroviral infections - airborne - is the fastest and most unpredictable. No less effective is the way the infection enters the human body through the food route and oral-fecal. There is also a vertical route of infection - from the carrier mother to the newborn. And it is with this phenomenon that many pediatricians associate sudden infant death syndrome.
What kind of animal is this?
Let's take a closer look at which microorganisms cause enterovirus infection. Pathogenic agents are viruses - extracellular life forms that parasitize in the cells of a living organism. The uniqueness of this group is in the minimum of structural components outside the cell (virions) and the ability to start the synthesis of its own genetic material at the expense of the host cell's resource.
The main task of the virion is to get inside the cell,which is achieved by the specific structure of the shell of viruses (capsids). Once infiltrated, this parasite can behave in a variety of ways, playing out scenarios that differ in levels of autonomy:
- The scenario is productive (of course, from the point of view of the virus): the parasite starts the synthesis of its own genetic material according to its own schedule, depleting the cell's resource and leading to its death.
- Another scenario is conciliation. Here the parasite incorporates its genome into the genome of the host cell and replicates its nucleic acids covalently with it.
Further development goes in two ways. In the first, the virus freezes, and only under certain conditions its genes turn on, producing a young generation of parasites that leave the dying cell. In the second variant of development, the virus genome constantly replicates, but the cell does not die. The young generation of virions is pushed out by exocytosis.
Microbiology of enteroviruses
The group of causative agents of enterovirus infections in humans includes representatives of the Picornaviridae family. This family includes more than 60 pathogens from the genus enteroviruses (Enterovirus), rhinoviruses (Rinovirus), cardioviruses (Cardiovirus) and autoviruses (Aphtovirus).
The genus of enteroviruses includes poliomyelitis viruses (3 forms or serotypes), Coxsackie viruses of group A (24 serotypes) and B (6 serotypes), ECHO (Enteric Cytopathogenic Human Orfhan - intestinal cytopathogenic human orphans, 34 serological types), hepatitis A virus and manyunclassified enteroviruses. All of them have a number of similar structural features:
- These are small viruses (from pico - "small"), measuring within 28 nanometers.
- They have a cubic type of capsid built from 4 types of proteins.
- Have a common complement-fixing antigen for the whole genus, serotypes differ in type-specific protein antigens.
- The genetic material is single-stranded linear RNA.
- External supercapsid shell, no carbohydrates and lipids.
- Have high stability in the external environment. That is why stomach acid does not kill them.
Pathogenicity and resistance
Representatives of this genus are ubiquitous, affecting plants, animals, bacteria. Enteroviruses enter the body in various ways, mainly through the digestive tract, reproduce in the mucous membranes and lymph nodes, enter the bloodstream and spread throughout the body. Damage to one or another organ depends on the type of pathogen and the immune status of the recipient.
Enteroviruses are common on all continents of the planet. They remain contagious (infectious) in the environment for up to a month, and in feces for up to six months. Frost-resistant, but die when heated to 50 °C. They remain pathogenic in acidic environments (they are not afraid of gastric juice), are resistant to the action of 70% alcohols, but are destroyed by ultraviolet and ultrasound.
When disinfecting rooms and objects, oxidizers are used(hydrogen peroxide and potassium permanganate), chlorine-containing agents, formaldehyde, which inactivate the pathogen.
Diagnosis of enterovirus infections
The specificity of diagnosing pathogens of this group of diseases is based on the identification of all pathogens present in the body. The material for research is feces and urine, swabs from the affected areas of the mucous membranes, blood and cerebrospinal fluid. The following methods are used to diagnose enterovirus infections:
- Virological study. This technique uses cell cultures and laboratory animals. For example, continuous cultures of monkey renal epithelium are used to determine all serotypes of the poliomyelitis virus. A polymerase chain reaction is also used.
- Serological samples. The method of paired sera and the production of color samples are used. The method is based on the ability of viruses to suppress cell metabolism, change the pH of the medium and, accordingly, the color of the test sample.
- Express method. Quite complex and not widely used. Cardiac analysis is used for diagnosis (changes in the nuclei of affected cells).
Many triggers – many manifestations
Forms of enteroviral infections according to modern classification:
- Intestinal, or gastroenteric. The illness lasts from one to two weeks. Clinical manifestations: rhinitis, swelling of the mucous membranes of the oropharynx, cough, flatulence, diarrhea and vomiting.
- Enterovirus fever. Symptoms: fever up to 40 ° C, weakness, muscle pain, redness of the sclera of the eyeball, nausea and vomiting, in rare cases - diarrhea. The disease lasts 3-7 days. The causative agents are enteroviruses of all subtypes.
- Catarrhal or respiratory (herpangina). The disease lasts up to a week and proceeds as acute respiratory. Caused by Coxsackie A and B. Symptoms: short-term fever with slight fever, sore throat, sores on the walls of the pharynx and tonsils, loss of appetite.
- Intestinal infection. The duration of the disease in young children is up to 2 weeks, in older and adults - 1-3 days. Only the intestinal mucosa is affected. Clinic: abdominal pain, frequent and loose stools, diarrhea, possibly a slight increase in body temperature.
- Myocarditis. Disorders of the heart in connection with the defeat of its different layers. Symptoms are associated with increased heart rate, fatigue, weakness, decreased pressure, and chest pain. Pathogens - Coxsackie B5 and ECHO.
- Exanthema. Within 3-5 days, a rubella-like rash appears on the face and body.
- Conjunctivitis. Symptoms: pain in the eye, blurred vision, lacrimation and hemorrhage, there may be an increase in lymph nodes. The illness lasts up to two weeks. Pathogens: enterovirus serotype 70, Coxsackie 24.
- Meningitis and encephalitis. The most severe form of enterovirus infection. Clinical manifestations: severe pain, high fever, vomiting, delirium, convulsions. The course of the disease is intermittent outbreaks that can last up to 2 months. The causative agents of this form are Coxsackie B and ECHO viruses.
- Paralytic form. It is accompanied by unilateral or bilateral paralysis of the limbs, a decrease in muscle tone. Symptoms can persist for up to 8 weeks, with severe development, a fatal outcome is possible due to violations of the respiratory center.
- Epidemic myalgia. A rather rare disease that manifests itself in paroxysmal pain in the muscles, in the chest and abdomen. Accompanied by fever and increased sweating. The duration of the course is up to 10 days. Pathogens - Coxsackie B3 and B5.
- Encephalomyocarditis of the newborn - in 60-80% leads to death. The causative agents are Coxsackie viruses of group B. Symptoms: lethargy, convulsions, heart failure, refusal to breastfeed.
The incubation period in all cases lasts from 2 to 15 days. The onset of the disease is always acute. There may be mixed forms of infection.
Pathogen entry gate
Before you ask yourself how to treat an enterovirus infection in children, let's figure out how it enters the body. The entrance gate in this case is the mucous membranes of the respiratory tract and the digestive tract, where viruses enter the fecal-oral or airborne routes.
When a pathogen enters the mucous membranes, a local inflammatory reaction begins. This will end the infection with a sufficiently strong immunity. But if the immune status is weakened, and the virulence of the virus is high and its quantity is quite large, then the infection is generalized. It enters the bloodstream and spreads throughout the body inaccording to the tropic features of the pathogen.
Depending on the affected organ or tissues, the clinic and symptoms of the disease can be very diverse.
General symptoms and course of illness
The severity and duration of an enterovirus infection depends on many factors. These include:
- The virulence of the pathogen (the ability to resist the body's defense mechanisms).
- Features of tropism - the direction of the virus to damage certain organs and tissues.
- The immune status of the infected person. The higher it is, the more likely the organism's victory over the pathogen.
As it is already clear, viruses of this group can affect various systems and organs of our body. But regardless of the source of infection, the common symptoms of such infections are the following:
- The temperature during enterovirus infection rises from 38 ºС to 40 ºС.
- Swelling of the submandibular and other lymph nodes.
- Weakness and drowsiness.
- Rash in some cases.
- Nausea, vomiting and diarrhea.
Preventive measures
There are no special methods of prevention in this case. In order to avoid infection, it is necessary first of all to observe the rules of personal hygiene: wash hands and food, drink boiled and purified water. Avoid visiting crowded places during an outbreak. But, perhaps, the main thing is to monitor the state of the body and increase immunity. He althy lifestyle, proper nutrition andphysical activity will minimize the possibility of a viral attack.
If there is an infected family member, all contacts should be more careful about preventive measures. Separate utensils and personal hygiene items for the patient and increased attention to the personal hygiene of all family members should be a priority.
In children's institutions, quarantine is introduced in case of outbreaks of enterovirus infections, which is set for 14 days from the moment of the last contact, and anti-epidemic measures (disinfection) are carried out. Maternity hospitals are also quarantined, and all employees who had contact with patients are sent on vacation for two weeks.
How to treat enterovirus infection in children?
Children, due to their immune status, are more susceptible to such diseases. If you suspect an enterovirus infection in a child, you should contact a pediatrician and get a referral for the research necessary in a particular case. Sometimes it may be necessary to consult doctors of narrow speci alties - a cardiologist, an otolaryngologist or an ophthalmologist.
Treatment of mild forms of the disease is carried out on an outpatient basis, and only if meningitis, myocarditis and other combined lesions are suspected, a child may be hospitalized. There are no specific drugs for enterovirus infection. Treatment focuses on reducing negative symptoms, preventing dehydration, and early detection of side effects.
Usually the bodycopes with the infection on its own within a week, and no significant consequences of enterovirus infections are observed. To maintain the body, usually symptomatic (for example, antipyretic) and pathogenetic drugs (sorbents and antiseptic ointments) are prescribed. There are no dietary restrictions, but it is worth remembering that nutrition for enterovirus infection should be balanced and take into account the nature of the disease. So, when the oropharynx is infected, food should not be hot or cold, which will ease the pain when it is swallowed.
Antibiotics are prescribed for secondary infections and complications of enterovirus infection, such as pneumonia, otitis, myocarditis. In some forms of diseases, hormonal drugs are prescribed. But all these appointments should be made by the doctor after a thorough study of the results of the research and taking into account the patient's condition.
The most typical enterovirus diseases
It is impossible not to list the most common and considered typical infections caused by enteroviruses. These include:
- Summer flu. The most common infection occurs when swimming in rivers and at sea. Overheating and hypothermia contribute to the development of infection. The symptoms combine flu-like symptoms and intestinal upset. The disease lasts from 3 to 7 days, accompanied by fever, diarrhea, sore throat, sometimes conjunctivitis.
- Gerpangina. Eruptions like herpes in the back of the throat and on the tonsils. The disease disappears in 3-5days.
- Viral pemphigus. The appearance of bubbles filled with liquid on the palms, between the fingers, on the soles. Fever accompanies infection in the first 1-2 days, symptoms disappear within a week.
- Viral exanthema. It is caused by echoviruses and is accompanied by a rubella-like rash all over the body. Less common, symptoms disappear within ten days.
In conclusion, I would like to note that this group of diseases is characterized by such a phenomenon as virus carrying. Often adults do not get sick, but are virus carriers. But children, with their still unstable status of the immune system, are easily infected. Therefore, observance of the rules of personal hygiene is mandatory for both adults and children. And remember - the key to the victory of the body over viruses that constantly attack it is a strong natural immunity. Stay he althy and take care of yourself and your children!
