Chickenpox vaccination

Varicella (chickenpox) is an acute systemic infectious disease caused by the herpes zoster virus (human herpes virus type 3). Chickenpox, a highly contagious infection, is spread by:

• airborne – the virus is introduced through the mucous membrane (usually the nasopharynx);
• direct contact with the virus – in the presence of lesions on the skin.

Chickenpox is most contagious during the prodrome and in the early stages of the rash. The disease is transmitted 48 hours before the first skin lesions appear and until the last lesions have crusted over. An indirect route of transmission, through immunized patients, does not occur.

Every year in the Russian Federation, doctors fix about 500 thousand cases of chicken pox.

The first rash in the form of a patchy rash may be accompanied by a short reddening of the skin. In the first hours, lesions progress to papules and then to characteristic, sometimes pathognomonic, vesicles, often intensely itchy, on an erythematous base. These elements are converted into pustules, and then covered with a crust. Focal lesions develop from macules to papules and vesicles, which then crust over. A distinctive feature of chickenpox is that the lesions appear in groups, so they are at different stages of development in any affected area. The rash may be generalized (in severe cases), involving the trunk, limbs, face, or more limited, and almost always affects the upper trunk. Ulcerative lesions can be found on mucous membranes: oropharynx and upper respiratory tract, palpebral conjunctiva, rectal and vaginal mucous membranes.

New rashes usually stop appearing by the 5th day. Most of them are covered with a crust by the 6th day; almost all crusts disappear in less than 20 days after the onset of the disease.

In immunocompetent children, chickenpox is rarely a severe disease. In immunocompromised adults and children, the infection can often be severe.

Cases are reported when in persons who have had chickenpox, the virus persists in the intervertebral ganglia. It can be activated after some time, and then the disease develops in the form of herpes zoster. The incentive to activate the infection is age after 5 years, the presence of HIV status and weakened immunity. Shingles in most cases is accompanied by pain and can lead to cranial nerve palsy, as well as visual impairment. In cancer patients and HIV-positive patients, a lethal outcome is possible. It is worth noting that people with obvious manifestations of herpes zoster can infect unvaccinated children and even a certain group of adults.

Chickenpox is sometimes complicated by varicella pneumonia and encephalitis. In addition, after a repeated disease, noticeable scars remain on the skin, the spread of the inflammatory process to soft tissues and the development of sepsis are possible.

Fatal outcomes from complications caused by the disease, in most cases, are observed in adults. Children tolerate the infection more easily, so the mortality rate among them is almost 40 times lower.

Indications for vaccination

In order to prevent children, vaccination begins after 1 year and older. It is carried out for:

• children older than 2 years who have not had chickenpox;
• children who are over 2 years old and go to health camps for children in the summer.

In addition, vaccination is required for:

• persons who have chronic diseases in severe form;
• patients with acute leukemia;
• people who receive drugs to increase immunity;
• people who have undergone chemotherapy;
• patients who are scheduled for transplantation.

Vaccination is carried out only in the absence of signs of insufficiency of cellular immunity. In addition, patients with chronic diseases are vaccinated only with a positive assessment of the state of health, before transplantation, the vaccine is administered 1-2 weeks before surgery.

Contraindications for vaccination

Contraindications for vaccination are most often temporary. The most common is an allergic reaction to the components of the vaccine. Among the main and common contraindications are:

• acute infectious and non-infectious diseases;
• leukemia;
• HIV AIDS;
• pregnant and lactating women.

Vaccination is carried out only to persons who are not in this group, however, there are exceptions. About all the pros and cons, it is better to consult directly with your doctor, who will determine the risk of vaccination against chickenpox.

Vaccination schedule

Vaccination is carried out subcutaneously for children from 1 year to 13 years of age once. Adolescents over 13 years of age and adults are vaccinated against chickenpox twice. It is important to observe the interval between vaccinations from 6 to 10 weeks.

In patients at risk and chronic diseases, the level of protection is somewhat reduced, therefore, this category of people is recommended to periodically take tests to detect antibodies and, if necessary, revaccinate.

With regard to emergency vaccination, it may be useful if the interval between contact of a sick person and a healthy unvaccinated person is less than 96 hours. When vaccinated during this period, the level of protection will be approximately 90%, but even with a lower level of protection, chickenpox will proceed much weaker than in an unvaccinated person.

It is worth noting that the varicella vaccine is generally well tolerated. Reactions to the vaccine are extremely rare, they appear locally at the injection site in the form of swelling, redness, induration and soreness. Similar phenomena develop on the first day after vaccination and disappear in a few days. It is also possible to increase body temperature, allergic rash, weakness, itching, and so on.

Treatment period

A mild form of chickenpox in children requires only symptomatic treatment. Relieving itching and preventing scratching of the skin, which predisposes to a secondary bacterial infection, can be difficult. Wet compresses will help, with severe itching – systemic antihistamines and baths with a colloidal solution of oatmeal.

Oral antiviral agents, when administered to immunocompetent patients in the first 24 hours after the onset of the rash, slightly reduce the duration and severity of symptoms.

It is recommended that oral valaciclovir, famciclovir, or aciclovir be given to healthy individuals at risk of moderate or severe infection, including patients:

• 12 years or older;
• having skin diseases, in particular eczema;
• with chronic lung disease.

The dosage of drugs is prescribed by the attending physician. To prevent secondary bacterial infection, patients should bathe regularly and keep their underwear, hands, and nails clean. Antiseptics should not be used unless the lesions are infected; bacterial superinfection is treated with antibiotics. Patients are not allowed to attend school, work, until the last lesions are covered with a crust.

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