Chickenpox (chickenpox) is an infectious disease caused by a virus called Varicella Zoster. The disease is characterized by the appearance on the skin and mucous membranes of a papulovesicular rash against a background of general intoxication.

Chickenpox is an infectious disease with characteristic symptoms In most cases, a person becomes infected with the disease in childhood, in adults, the infection is quite rare. The chickenpox virus can be localized in the nerve ganglia and remain latent in the body for life.. But sometimes it becomes active, causing a disease such as shingles (most often in the elderly).

In children of the first year of life, chickenpox rarely occurs, since they receive antibodies from the mother. With a significant decrease in the body's defenses, re-infection with an infection may occur.

The first information about chickenpox appeared in the middle of the XVI century and was described by Italian doctors. The disease was originally thought to be of the same nature as smallpox (Variola). In 1772 the German physician O. Vogel coined the name Varicella. Chickenpox began to be considered a separate nosological form after an epidemic at the end of the 19th century..

The causative agent of chickenpox is a genomic DNA virus belonging to the genus Varicellovirus and a member of the subfamily Alphaherpesvirinae. It was discovered in 1911 by the Brazilian physician E. Aragao in the contents of the bubbles. Varicella Zoster is classified as a type 3 herpes virus.

The varicella-zoster virus multiplies only in the human body. In the environment, it dies very quickly when exposed to heat or sunlight.. In particles of mucus that gets into the air from the nasopharynx, the virus can live no more than 15 minutes.

Epidemiology of chickenpox The source of infection is a sick person. It is considered contagious from the 10th day of the incubation period to the 6-7th day of the disease. Virus transmission mechanism - aerosol. It is secreted by coughing, sneezing, talking and spread by airborne droplets. The varicella-zoster virus can be carried long distances (to adjacent rooms or other floors).

The virus is transmitted by airborne droplets Since it cannot be outside the human body for a long time, the disease is not transmitted by contact-household means. But infection can occur transplacentally (the infection crosses the placenta from mother to fetus).

The natural susceptibility of a person to the causative agent of the disease is almost one hundred percent, therefore, in about 90% of cases, chickenpox is transferred in childhood (up to 15 years). The disease is spreading everywhere. Most often it is celebrated in kindergartens and elementary schools.. The peak of the disease occurs in the autumn-winter period..

A characteristic feature of the epidemiological processes of chickenpox is the absence of recessions and rises in the disease. This is because all susceptible patients get sick at almost the same time.. At the same time, after an illness, a person develops a stable lifelong immunity..

The pathogenesis of chickenpox The infection enters the human body through the mucous membranes of the respiratory tract. The virus invades the epithelial cells and begins to actively multiply. In the future, regional lymph nodes are affected.

At the end of the incubation period, the virus begins to circulate in the general bloodstream, causing the patient to become intoxicated.. Fever is caused by the accumulation of toxic metabolites in the blood.

The virus circulates throughout the body, but further its localization is determined by attachment to epithelial tissues and mucous membranes.. The cells die and die off, and in their place cavities filled with exudate appear (vesicles are formed). After opening them, crusts form. Rashes on the mucous membranes turn into erosion.

Symptoms of chickenpox The incubation period of the disease is from 10 to 21 days, during which time the infection enters the bloodstream. Then the symptoms of the disease begin to appear..

The prodromal period may be accompanied by an increase in body temperature, headache, nausea. The prodromal period may last 1–2 days. It is often mild in children.. At the same time, the child becomes lethargic, whiny, his excitability increases and his appetite decreases. In adults, this period is more pronounced, often accompanied by an increase in body temperature, headache, nausea and vomiting..

The appearance of a rash A pronounced clinic of the disease develops from the moment the first rash appears (sometimes it occurs against the background of complete well-being). In a patient with an acute form of chickenpox, the body temperature rises to 38–40 ° С, symptoms of intoxication increase.

In an adult, the rash appears later than in a child, and the signs of intoxication are more pronounced. Body temperature rises to high numbers (39-40 ° С) and lasts longer. The temperature curve has no special differences.

Red spots form on the skin, which after a few hours turn into nodules (papules), and then into single-chambered vesicles filled with a clear liquid (vesicles). After piercing, they fall off, and crusts appear in this place.. At the same time, severe itching is noted..

During the same period, a new rash appears on the skin.. Therefore, spots, papules, vesicles and crusts can be observed on one area of \u200b\u200bthe skin.. A rash with chickenpox affects only the upper layer of the epidermis, so it disappears without a trace. But when scratching, damage to the growth layer occurs, which leads to the formation of atrophic scars in place of the vesicle..

Transformation of vesicles into pustules Sometimes the vesicles suppurate, forming pustules filled with a cloudy liquid. The patient's condition worsens. Significant damage to the skin causes pits to form in the center of the pustules.

Subsequently, after the crusts fall off, scars (so-called pockmarks) form at this place. It should be noted that in adults, vesicles are transformed into pustules much more often.. In this case, the rash appears later and lasts longer..

The rash is localized on the trunk, scalp, face and limbs, excluding the surface of the soles and palms. For several days, dripping occurs, while the body temperature rises. After the new rash stops appearing, intoxication decreases.

Specific forms of the disease In a mild form of the disease, the symptoms of chickenpox are blurred. In this case, the fever may be absent, and the elements of the rash are isolated.

People with a weakened immune system (more often adults) may have specific forms of the disease:.

Chickenpox shape.

Description.

Hemorrhagic.

Patients develop vesicles filled with bloody contents, nosebleeds develop.

Bullous.

The skin becomes covered with large flabby blisters, which transform into poorly healing ulcers.

Gangrenous.

Vesicles enlarge rapidly, their contents become bloody. After drying, black crusts with an inflammatory rim appear on the skin..

neboleem. net.