Varicella (chicken pox) in children

Chicken pox (chicken pox) is an acute viral infection that causes mild fever and the appearance on the skin, mucous membranes of small vesicles with clear contents.

Chickenpox is a typical childhood infection. Virtually the entire population of the world has chickenpox in the age of 10-14 years.

Epidemiology

The only source of chickenpox is a sick person. The patient is contagious one day before the appearance of the first rash and within 3-4 days after the appearance of the last vesicles, especially at the time of the onset of rashes. The source of infection can be and patients with herpes zoster. The causative agent of chickenpox is present in the contents of the vesicles, but is not found in the scabs.

Chickenpox is transmitted by airborne, less often by contact, with the possibility of infection at a great distance. The virus easily spreads with air current through the ventilation system, staircases from floor to floor. Transplacental transmission of the virus from the mother to the fetus has been proven.

Children of the first 2-3 months of life are ill with chicken pox rarely. However, in the absence of immunity, the mother can get sick and the newborn. After the infection, a lasting immunity remains. Repeated diseases are rare, not more than 3% of cases.

[1], [2], [3], [4], [5], [6], [7],

Causes of the chicken pox

The causative agent of chicken pox (varicella) is the third type of herpes virus, containing DNA; by properties close to the herpes simplex virus and indistinguishable from the causative agent of herpes zoster, which is therefore designated as the varicella zoster virus.

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Pathogenesis

The entrance gate of the infection is the mucosa of the upper respiratory tract. Here the primary multiplication of the virus begins. By the lymphatic ways, he gets into the blood. By the current of blood, the virus enters the epithelial cells of the skin and mucous membranes and is fixed there. Bubbles are formed, filled with serous contents, in which the virus is in high concentration. In addition, the varicella-zoster virus has a tropism to the nerve tissue, is capable of damaging the intervertebral ganglia, the cerebral cortex, the subcortical region and especially the cerebellar cortex. In very rare cases, possible damage to visceral organs, especially the liver, lungs, digestive tract.

[9], [10], [11], [12], [13], [14]

Symptoms of the chicken pox

The incubation period of chickenpox (chicken pox) is 11-21, on average - 14 days. Chickenpox (chicken pox) begins with an increase in body temperature to 37.5-38.5 ° C and the appearance of a wind-blown rash.

The primary element of the rash is a small spot-papule that quickly, after a few hours, turns into a vesicle 0.2-0.5 cm in diameter. The varicella vesicles have a round or oval shape, are superficially located on a non-infiltrated base, surrounded by a corolla of hyperemia, their wall tense, the content is transparent. Individual vesicular elements have an umbilical impression in the center. Vesicles usually single-chambered and drop when punctured. At the end of 1, less often on the 2nd day after the onset of the rash, the vesicles dry up and turn into a brown crust falling off for 1-3 weeks of the disease. After the separation of crusts for a long time (up to 2-3 months) you can see gradually "fading" pigment spots, but scarring is not formed. Eruptions are located on the face, the scalp, on the trunk and extremities. On the palms and soles of the rash usually does not happen.

Often, vesicular rashes appear and on the mucous membranes of the mouth, conjunctiva, rarely - on the mucous membranes of the larynx, genital organs. Elements of the rash on the mucous membranes are tender, quickly opened and transformed into surface erosion, and there may be a slight soreness. Healing of erosions occurs on the 3-5th day of the appearance of rashes.

When chicken pox rashes appear not simultaneously, but as if jerky, with intervals of 1-2 days. As a consequence, on the skin you can see the elements at different stages of development - macula-papules, vesicles, crusts. This is the so-called "false polymorphism" of the rash, characteristic of chicken pox. Each new rash is accompanied by a new rise in body temperature, so the temperature curve for chickenpox is incorrect. Peripheral blood with chicken pox is practically unchanged. Sometimes small leukopenia and relative lymphocytosis are observed.

[15], [16], [17]

Forms

There are typical and atypical varicella.

Typical cases include cases with characteristic bubble rashes, filled with transparent contents.

Typical chicken pox by severity is divided into light, medium and heavy.

[18], [19]

Complications and consequences

With chicken pox, complications are specific, caused by the direct action of the virus, and can occur as a result of the attachment of a bacterial infection.

Among the specific complications of leading importance are chickenpox encephalitis and meningoencephalitis, less often myelitis, nephritis, myocarditis, etc.

[20], [21], [22], [23], [24], [25]

Diagnostics of the chicken pox

The diagnosis of chickenpox (chickenpox) is established on the basis of a typical vesicular rash all over the body, including the scalp. Rash undergoes a kind of evolution and differs polymorphism.

From laboratory methods, PCR is used to detect viral DNA in vesicular fluid and blood. For serological diagnosis, the complement and ELISA binding reaction is used. Attention is paid to the immunofluorescence method, with which you can detect the chickenpox in smears-prints from the contents of the vesicles.

[26], [27], [28], [29]

Treatment of the chicken pox

It is necessary to strictly monitor the hygienic content of the child, the cleanliness of bed linen, clothes, hands. Vesicles are lubricated with 1% solution of brilliant green or 1-2% with potassium permanganate solution. Recommended common bath with a weak solution of potassium permanganate, mouthwash with disinfectant solutions after eating. It is advisable to treat the vesicles with 5% cycloferon liniment. When there are purulent complications, antibiotics are prescribed. Glucocorticoid drugs with chickenpox are contraindicated, but with the occurrence of chickenpox encephalitis or meningoencephalitis they have a positive effect. In severe forms, an antiviral drug is administered from the group of acyclovir at a rate of 15 mg / kg per day orally or intravenously, as well as a cycloferon injection solution of 10 mg / kg. Such therapy cuts off the flow of chicken pox.

Treatment of varicella (chicken pox) with antiviral drugs is quite effective in the development of complications of chicken pox (encephalitis, pneumonia, etc.). There are reports about the antiviral effect of anaferon in children, the inclusion of which in standard varicella therapy has made it possible to significantly reduce the duration of the course of the main clinical symptoms and reduce the number of bacterial complications.

Prevention

The patient with chickenpox (chickenpox) and herpes zoster is isolated at home until 5 days after the last rash. Only children with severe or complicated forms of illness are subject to hospitalization, they are necessarily placed in the Mel'tserovsky box. With meningoencephalitis, hospitalization is mandatory. Children of toddlers (up to 3 years old) who were in contact with patients with chicken pox and herpes zoster and who had not been sick before are isolated from the 11th to the 21st day from the moment of contact. Final disinfection in the focus of infection after isolation is not carried out because of the instability of the virus. It is enough to ventilate the room after isolating the patient and make a wet cleaning. Vaccination against chicken pox is also used .

[30], [31]