Viral meningitis

Viral meningitis is considered one of the relatively favorable types of inflammation and is most often treated on an outpatient basis. Viral meningitis mainly affects children, less often young people under 30 years old, the epidemiological peak occurs in the summer and is associated with an outbreak of enterovirus infections, respectively, the causative agent of the disease in 80% of cases is RNA-containing enteroviruses ECHO. Like other types of meningitis, viral inflammation in the pathogenetic sense can be both primary and secondary - developing as a symptom or concomitant complication of an infectious disease (pneumonia, mumps, poliomyelitis, rheumatism, brucellosis, etc.).

Meningitis, inflammation of the meninx - the meninges, can be caused by various pathogens - viruses, bacteria, mycoplasmas and even parasites. Most often, the very concept of "meningitis" causes panic, especially when a child falls ill. Indeed, the inflammatory process of the soft, arachnoid membrane of the brain, both cerebral and spinal, is a serious disease, but it varies in classification etiology, accordingly, it can occur in different forms and has different localization - spinal, cerebral.

How is viral meningitis transmitted?

Serous, aseptic meningitis is a contagious inflammatory process that previously had a high epidemiological threshold due to poliomyelitis. Since the 60s of the last century, epidemic outbreaks have become much less common due to widespread vaccination against poliomyelitis. However, in the summer and early autumn, isolated forms of meningitis are regularly recorded, mainly among young children.

How is viral meningitis transmitted? There is only one answer - only by contact through the nose or mouth. The source of infection is always a sick person - a virus carrier, the transmission route is most often airborne, less often - oral-fecal. Very rarely, viral meningitis is transmitted placentally, that is, from an infected mother to the fetus. Depending on the route of infection, the virus can enter either the digestive tract or the nasopharynx, causing inflammation of the pharynx, respiratory system, and less often abdominal pain. Penetrating the bloodstream, the virus enters the serous membranes of the brain, but rarely penetrates the cerebrospinal fluid, the spinal fluid.

Viral meningitis is transmitted in the following ways:

• Saliva.
• Sputum when coughing.
• Nasal mucus when sneezing, blowing your nose.
• Feces (rare).

The main way of transmitting meningitis in children is dirty hands that have had contact with virus-infected objects, infected people (hugs, kisses, etc.). You can also become infected through virus-infected water or food. When in contact with a sick person, an adult most often risks getting a viral infection, but not meningitis; children are more susceptible to this disease, since their immune system is still forming.

Causes of viral meningitis

Most often, the causes of viral meningitis are associated with Enterovirus, that is, viruses that multiply in the digestive tract. Reproducing in the intestine, enteroviruses of the ECHO and Coxsackie species very rarely provoke enteritis itself, more often causing encephalitis, meningitis, acute respiratory infections, myocarditis, specific conjunctivitis (hemorrhagic), epidemic myalgia (pleurodynia).

The enterovirus group is included in the Picornaviridae family – picornaviruses, very small in size and containing RNA. Of all the 67 serotypes known to medicine, 40 are extremely pathogenic strains. In 90% of cases, the causes of viral meningitis are Coxsackie viruses and Enteric Cytopatthogenic Human Orphan serotypes, abbreviated to ECHO. Interestingly, part of the definition of the Human Orphan virus is translated as "orphan". Indeed, for a long time from the day of its discovery in 1951, it could not be attributed to a specific disease. Also, before the discovery of a vaccine that defeats poliomyelitis, meningitis was provoked by polioviruses for a long time, currently such cases are almost never encountered.

In quantitative terms, the causes of viral meningitis look like this:

• Most often in 85-90% of cases:
  • ECHO viruses and Coxsackie viruses.
• Less often, in 10-15% of cases:
  • Epidemic mumps.
  • Herpes simplex virus (type II).
  • Coriomeningitis.
  • Arthropod borne viruses – arboviruses (through the bites of arthropod insects).
  • Cytomegalovirus.
  • Influenza viruses.
  • Togaviruses (rubella).

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Symptoms of viral meningitis

The clinical picture of serous aseptic meningitis is quite clear, although in the prodromal stage there may be symptoms characteristic of the underlying infection, such as influenza. Symptoms of viral meningitis may appear later and are differentiated quite quickly.

In addition, in clinical practice, characteristic signs have been noted that are distributed across age groups of patients:

• In newborns, serous meningitis often manifests itself with symptoms of encephalomyocarditis.
• Children under six months of age suffer from enterovirus diarrhea.
• Children aged one to three years – poliomyelitis-like symptoms (convulsive, paralytic forms).
• Children three years and older – high blood pressure, hyperthermia, severe headache, vomiting, fever.
• Adults suffer from a milder form of the disease, called pleurodynia - epidemic myalgia.

General typical symptoms of viral meningitis:

• Prodromal stage – malaise, inflammation of the mucous membranes of the nasopharynx (catarrhal signs).
• Severe headache.
• Pressing pain in the eyeballs.
• Hyperthermia up to 40 degrees.
• Pain in the neck and along the spine.
• Nausea and vomiting.

Meningeal signs appear after 3-5 days and may be as follows:

• Rigidity, tonic tension of the neck muscles.
• Kernig's sign (inability to straighten the leg at the knee) and Budzinski's sign (flexion of the lower leg and thigh) are rare in acute meningitis.
• Hyperesthesia – photophobia, intolerance to noise, sounds, physical contact.
• Inflammation of the lymph nodes - with secondary serous meningitis against the background of mumps.
• Skin rash - with viral meningitis caused by the Coxsackie serotype, the ECHO virus.
• Asymmetry of tendon reflexes - anisoreflexia.
• Herpetic vesicles of the larynx in meningitis caused by the Coxsackie virus.
• Rarely - subcomatose state - stupor.

It should be noted that the symptoms of aseptic meningitis are usually similar to the clinical picture of the flu, typical meningeal manifestations, such as rigidity, rashes, are weakly expressed and not in a complex. Despite the general poor health, a person who has contracted viral meningitis tolerates the disease much easier than bacterial meningitis.

It is not only impossible, but also dangerous to diagnose meningitis in yourself or your child, but there are the following signs that should alert you and force you to urgently consult a doctor:

• Severe headache, vomiting against the background of any infectious disease - acute respiratory viral infection, rubella, chickenpox, mumps, herpes.
• Elevated body temperature, accompanied by pain in the back and neck (the pain increases when turning and raising the head).
• Confused, delirious consciousness against the background of high temperature.
• Convulsive syndrome.
• Newborns have a high temperature and a bulging fontanelle.
• Skin rash associated with high fever.
• Incubation period for viral meningitis.

The incubation period of the virus can vary from 2 to 10 days, but most often the incubation period for viral meningitis lasts no more than four days. At the end of it, the clinical picture of the disease begins to appear, symptoms that are typical for serous meningitis. The patient is dangerous in terms of infecting others for ten, less often twelve days, as soon as the first signs of meningitis appear, the person stops releasing viruses. It should be noted that depending on the type of pathogen, the incubation period for viral meningitis can vary as follows:

• Enteroviruses (Coxsackie, ECHO) – 1-18 days, most often from 3 to 8 days.
• Meningitis caused by the mumps virus - up to three weeks, more often from 10 to 18 days.
• Acute aseptic meningitis (Armstrong's choriomeningitis) - from eight to twelve days.

Whatever the type of meningitis, its incubation period, people who care for the patient should observe the rules of personal hygiene, treat objects, toys, dishes to minimize the risk of infection.

Viral serous meningitis

Meningitis, which is diagnosed as viral, is a whole group of diseases that provoke inflammation of the serous, soft membranes of the brain and spinal cord. Meningitis of this type, like other types, can be primary or secondary, that is, developing against the background of the main infectious process. The main pathogens are considered to be more than 40 serotypes of enteroviruses, as well as Armstrong arenavirus, which causes choriomeningitis (lymphocytic).

Pathogenetically, viral serous meningitis is divided into the following types:

Meningitis caused by Coxsackie serotypes, ECHO viruses

The source of infection is a person with meningitis, as well as people in contact with them. Enteroviruses are carried by animals, insects, the standard route of infection is airborne, less often - oral-fecal. Epidemiology is characterized by seasonality, most often children get sick with such meningitis in the summer. Viral serous meningitis provokes inflammation of the membranes of the brain, swelling of its substance, the virus can also affect internal organs:

• heart (myocarditis, pericarditis),
• lungs (pleurisy),
• muscles (myalgia).

The virus incubation period lasts from 3 to 9 days. Symptoms may be clearly expressed in the acute form of primary meningitis, or be blurred in the mild course of the disease. As a rule, serous meningitis proceeds quickly, without a prodromal period and ends with a favorable outcome. 2.

Aseptic choriomeningitis or Armstrong's lymphocytic meningitis

This is an inflammatory disease affecting the soft meninges, as well as the substance, vascular plexus of the cerebral ventricles. Lymphocytic meningitis is usually accompanied by myocarditis, pneumonia, orchitis or mumps. Aseptic viral serous meningitis can occur in a latent form, most often young people under 30 years old, less often children suffer from it. The source of infection is rodents (rats, mice) that carry the virus. A person becomes infected with arenavirus through contaminated water (oral route), as well as through the alimentary route, when consuming products infected with the virus. The seasonality of epidemiological manifestations is winter and early spring, the incubation of the virus lasts up to 12 days. Symptoms are characterized by their hydrocephalic manifestations (cerebral edema), high blood pressure.

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Meningitis caused by mumps, or more precisely paramyxovirus

This is serous meningitis, more often diagnosed in children than in adults, and mainly boys get sick. The route of infection is airborne, the source is a sick person. The incubation period lasts a long time, up to three weeks. The stages of penetration of the virus into the membrane of the brain are the nasopharynx, bloodstream, blood-brain barrier and subarachnoid zone. The virus also penetrates into the internal organs - the testicles in males, appendages and ovaries - in women, into the pancreas.

Viral meningitis in children

Viral meningitis in children is a less dangerous type of disease than bacterial meningitis. However, the disease is classified as infectious, caused by viruses resistant to the external environment - Coxsackie and ECHO, less often by the arenavirus or mumps virus. The main reservoir of infection is a sick person or someone who comes into contact with him. The causative agent of the disease is transmitted as follows:

• Through contaminated water.
• Through dirty food products – fruits, vegetables.
• Through dirty hands.
• In crowded places by airborne droplets.
• When swimming in polluted waters - a pool, lake, pond.

Viral meningitis in children is characterized by the fact that it most often affects children from 2-3 years to 6 years old. Babies under six months rarely get meningitis due to the innate immune protection received from the mother's immunity, especially if the children are breastfed. Most often, outbreaks of serous meningitis are observed in the summer and autumn, sporadic cases of "winter" viral meningitis are almost never encountered.

Symptoms of viral serous meningitis:

• Elevated body temperature, up to 40 degrees.
• Severe headache, pain in the eyes.
• Nausea and uncontrollable vomiting.
• Myalgia (muscle pain).
• Neck muscle stiffness may occur.
• Rarely – diarrhea.
• Rarely – convulsive syndrome.
• Typical meningeal manifestations are not characteristic of viral meningitis.

As a rule, viral meningitis in children passes within 7-10 days, the temperature drops after 5-7 days, but relapses are possible. Treatment is carried out both in hospital for the acute form of the disease and outpatient, and consists of symptomatic therapy and bed rest.

The prognosis of the disease is favorable, there may rarely be residual effects in the form of fatigue, periodic headaches. Children who have had serous meningitis are subject to dispensary registration and observation by a neurologist.

Consequences of viral meningitis

Serous meningitis is considered less dangerous than bacterial meningitis. Viral meningitis has favorable consequences in 90% of cases with timely diagnosis and symptomatic treatment. Meningitis of this type is benign, but can recur and be accompanied by the following phenomena:

• Cerebrasthenia – transient headaches, fatigue, temporary decline in cognitive functions – in 35% of cases.
• Neuroses, irritability, sensitivity, emotional instability – in 10% of cases.
• Increased blood pressure, hypertensive-hydrocephalic syndrome – in 5% of cases.

Viral meningitis, the consequences of which usually pass within six months, may manifest itself in periodic complications at a later period - after a year or two. This occurs solely due to non-compliance with medical recommendations, including those related to bed rest. In addition, possible negative phenomena can be provoked by premature mental, emotional and physical stress. Thus, the main type of treatment after the discharge of a child or adult is compliance with a gentle regimen and some time restrictions.

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Treatment of viral meningitis

Treatment of viral meningitis is most often etiotropic, symptomatic, aimed at pain relief, rehydration, and lowering body temperature. As a rule, the classic course of viral meningitis is a form of a cold, slightly more complicated than usual, so it does not require any special treatment.

Antibacterial therapy is prescribed extremely rarely, in cases of secondary meningitis against the background of a certain form of infection. Interferon, acyclovir, immunoglobulins can be used.

Acute forms of serous meningitis require infusion therapy, detoxification with polyionic agents - hemodez, rheopolyhyukin, plasma. Less often, corticosteroids and barbiturates are prescribed, mainly for convulsive symptoms. After the most alarming symptoms have been relieved, the patient is prescribed nootropic drugs, B vitamins, a certain diet with the inclusion of protein, vitamin-rich food. After discharge, each person who has had meningitis is registered with the dispensary, observed by the treating neurologist and therapist.

Treatment of viral meningitis involves following a gentle regimen and lifestyle for at least 4 weeks, but it is better not to be exposed to physical, emotional and mental stress for 2-3 months until the body is fully restored.

How to prevent viral meningitis?

Since viral meningitis is transmitted by airborne droplets and directly depends on hygiene, rules for processing food and objects, preventive measures are quite simple - first of all, hygiene, avoiding contact with patients with acute respiratory viral infections, flu, mumps, and processing water and food.

In addition, prevention of viral meningitis is a timely visit to the doctor at the first signs of the disease, since it is the identification of sources of infection that helps to significantly reduce the speed and quantitative indicator of the spread of infection. Timely isolation of virus carriers, up to the appearance of the first symptoms, can minimize the risk of infection of both the patient's relatives and many other people around him. Another means of prevention is immunotherapy, for example, instillation of interferon three times a day for a week.

If a child attending a kindergarten falls ill with meningitis, the institution is quarantined for two weeks, all premises must be disinfected. The same applies to the house where the patient lives - all contacts are limited for 14 days, the rooms are treated with disinfectant solutions (3% chloramine solution, ventilation, destruction of insects, rodents).

It should be noted that prevention of viral meningitis in the epidemiological sense is difficult, since viruses are extremely common and resistant to external factors. In addition, their diversity (up to 40 known typical pathogens) does not allow developing uniform norms and standards suitable for all cases. That is why, observing the rules of personal hygiene, a reasonable approach to nutrition, a simple action - frequent sanitation, hand washing, can be the most effective way to help minimize the risk of infection with serous meningitis.