Adenovirus infection in children

Adenovirus infection in children is an acute respiratory disease with fever, moderate intoxication, damage to the mucous membranes of the respiratory tract, often the conjunctiva of the eyes, and also lymphoid tissue.

The disease occupies an important place in the pathology of young children. In the interepidemic period of influenza, the share of adenovirus infection at this age accounts for up to 25-30% of all viral diseases of the respiratory tract. By the age of 5, almost all children have had adenovirus infection, and half of the children suffer the infection again.

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Epidemiology

The source of infection are patients with both obvious and latent, inapparent forms of the disease, as well as healthy carriers. The most dangerous patients are those in the acute period of the disease, when adenoviruses are found in high concentrations in nasopharyngeal washes, scrapings from the affected conjunctiva, in blood and feces. Patients are dangerous during the first 2 weeks of the disease, in rare cases the virus is released for up to 3-4 weeks.

The mechanism of transmission of the infection is airborne, but the alimentary route of infection is also possible - like intestinal infections. According to the epidemiological classification of infectious diseases, adenovirus infection is classified in the group of airborne and intestinal infections.

Children in the first months of life are poorly susceptible to adenovirus infection due to passive transplacental immunity. Starting from 6 months, almost all children become susceptible. As a result of repeated diseases, children acquire active immunity; from the age of 5, the incidence of adenovirus infection decreases sharply.

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What causes adenovirus infection in children?

There are 41 known varieties (serovars) of human adenoviruses. Viral particles contain DNA, have a diameter of 70 to 90 nm, and are stable in the external environment.

Pathogenesis

The entry point for infection is most often the upper respiratory tract, sometimes the conjunctiva or intestine. By pinocytosis, adenoviruses penetrate the cytoplasm and then the nucleus of susceptible epithelial cells and regional lymph nodes. Viral DNA is synthesized in the nuclei of affected cells and mature virus particles appear after 16-20 hours. This process leads to the cessation of division of infected cells and then to their death. Virus reproduction in epithelial cells and regional lymph nodes corresponds to the incubation period.

Causes and pathogenesis of adenovirus infection

Symptoms of adenovirus infection in children

The incubation period of adenovirus infection is from 2 to 12 days. The disease usually begins acutely, but various symptoms of the disease do not appear simultaneously, but sequentially. The first signs are often an increase in body temperature and catarrhal phenomena in the upper respiratory tract. Body temperature rises gradually, reaching a maximum (38-39 ° C, less often 40 ° C) by the 2nd-3rd day. Symptoms of intoxication are moderate. Slight lethargy is noted, appetite worsens, headache is possible, muscle and joint pain is rare. Some patients experience nausea, vomiting, abdominal pain.

From the first day of the disease, copious serous nasal discharge appears, which soon becomes mucopurulent. The mucous membrane of the nose is swollen, hyperemic. Nasal breathing is difficult. Changes in the oropharynx include moderate hyperemia and swelling of the anterior arches and palatine tonsils. So-called granular pharyngitis is noted on the mucous membrane of the posterior wall of the pharynx, in which the posterior wall looks edematous and hyperemic with hyperplastic bright follicles, the lateral ridges of the pharynx are enlarged. With a pronounced exudative component of inflammation, delicate whitish plaque and thick mucus are visible on the hyperplastic follicles.

Symptoms of adenovirus infection

Classification

In case of adenovirus infection, the main clinical syndrome is distinguished:

• pharyngoconjunctival fever;
• catarrh of the upper respiratory tract;
• keratoconjunctivitis, tonsillopharyngitis;
• diarrhea;
• mesenteric lymphadenitis, etc.

A distinction is made between mild, moderate and severe forms without complications and with complications.

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Diagnosis of adenovirus infection in children

Adenovirus infection is diagnosed based on fever, symptoms of catarrh of the respiratory tract, hyperplasia of the lymphoid tissue of the oropharynx, enlargement of the cervical lymph nodes, and damage to the mucous membranes of the eyes. The consistent development of clinical symptoms is important for diagnosis, as a result of which the febrile period can be extended to 7-14 days.

The method of fluorescent antibodies is used as a rapid diagnostic, allowing to detect a specific adenoviral antigen in the epithelial cells of the respiratory tract of a sick child. For serological diagnostics, the RSC and the hemagglutination inhibition reaction (HIR) are used. An increase in the titer of antibodies to adenovirus by 4 times or more in paired sera in the dynamics of the disease confirms the etiology of the disease. Nasopharyngeal swabs, feces and blood of the patient are used to isolate adenoviruses.

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Adenovirus infection in children: treatment

Adenovirus infection in children differs from respiratory infections of other viral etiologies by damage to the mucous membranes of the eyes, non-simultaneous occurrence of the main clinical symptoms, a clearly expressed reaction of the lymphoid tissue, and pronounced exudative inflammation of the respiratory tract.

Adenovirus infection in children is treated syndromically in the same way as influenza. Paracetamol-containing drugs (Children's Panadol) are recommended as antipyretics for young children. Young children with severe adenovirus infection and complications are subject to hospitalization.

Adenovirus infection in children is treated at home. Bed rest and proper nutrition are prescribed. Symptomatic agents, desensitizing drugs, and multivitamins are used. It is recommended to instill a 0.05% solution of deoxyribonuclease into the nose, 3-4 drops every 3 hours for 2-3 days. Instillation of interferon into the nasal cavity is ineffective.

Specific prevention has not yet been developed. Conventional prevention methods are used: early isolation of the patient, ventilation and ultraviolet irradiation of the room, wet cleaning with weak chlorine solutions, boiling dishes, linen and clothing.

Diagnosis and treatment of adenovirus infection

Antibiotics are indicated only for bacterial complications: pneumonia, sinusitis, tonsillitis, etc. It is possible to use interferon inducers (for example, children's anaferon - for children from 6 months, and for children from 6 years of age - kagocel, which combines well with other antiviral drugs, immunomodulators and antibiotics).

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