Adenovirus infection symptoms

Adenovirus infection is a widespread, acute infectious disease characterized by damage to the mucous membranes of the respiratory tract, eyes, lymphoid tissue, liver, increased body temperature and moderate intoxication. Adenoviral diseases are widely spread both in the form of sporadic cases, and in the form of outbreaks. Most often, children suffer from it.

Etiology. Pathogens of adenovirus infection - viruses of the family.adenoviruses( family Adenoviridae).They do not have an outer( super-capsid) shell.

More than 80 antigenic types( serovars) are known, 41 of them are serovars from humans. The significance of serovars for humans is not the same. Some cause respiratory diseases( serovars 4 th, 7 th), others - pharyngitis( serovar 5 th), and third - external eye diseases( serovar 8th).The same serovar can cause different clinical forms.

Adenoviruses are medium-sized particles( 70-90 nm), contain double-stranded DNA with OMM 20-30 x 106. Infectious viral particles have the form of icosahedra with envelopes( capsids), 3 main soluble antigens are isolated: Ar-A, Ar-Band Ar-C, representing the subunits of viral structural proteins. Ar-A is responsible for the overall group specificity, complement-binding;Ar-B - for subgroup, is a carrier of toxicity, and Ar-C is responsible for the typical specificity, is revealed in the neutralization reaction.

Adenoviruses reproduce in tissue cultures, causing characteristic cytopathological changes. The first signs of cell damage appear after 12 hours. Unlike influenza and parainfluenza viruses, they multiply in the nucleus of the affected cells. And only after that they mature into the cytoplasm. Adenoviruses have hemagglutinating activity.

The sensitivity of adenoviruses to physicochemical agents. Resistant to ether and chloroform, relatively stable at pH 5.0-9.0 and temperature from 4 to 50 ° C.At a temperature of 56 ° C perish for 30 minutes, at 36 ° C - after 7 days, at 23 ° C are stored for 14 days. Lyophilic drying and low temperatures, including repeated freezing at -30 ° C, are well tolerated.

Epidemiological features. Adenovirus infection affects all age groups of the population. The maximum incidence rates are recorded every 5 years.

The epidemic process is characterized by low intensity, slow development and prolonged course.

Outbreaks of adenovirus infection occur throughout the year and are characterized by slow development and prolonged course( up to 1 -1.5 months).In children's preschool groups during outbreaks, 30 to 80% of children are ill, in schools - up to 40% of children.

The maximum infection of preschool children and schoolchildren is due to types 1, 2, 5, and toddlers type 3.

Adenovirus release begins 2-5 days before the disease, in the first week of the disease it is detected in 55.8% of patients, until the endThe third week - in 1/3 of patients. The maximum allocation of adenoviruses is 31 to 40 days.

Adenoviruses are found in 2.7-19.1% of healthy individuals. Possible long-term virus carrier( up to 300-900 days).

The mechanism of transmission of infection - airborne, but it is possible and fecal-oral, contact. Probably intrauterine infection.

Children of the first months of life are immune to adenoviral infection. Susceptibility increases from 6 months, from 7 years sharply decreases due to acquired immunity.

Features of pathogenesis. The entrance gates of infection are predominantly mucous membranes of the upper respiratory tract, less often - conjunctiva and intestines. In the nuclei of susceptible epithelial cells of the mucous membrane of the respiratory tract, viral DNA is synthesized, and mature virus particles form one day later. Affected cells die. Reproduction of adenoviruses can occur in intestinal tissue, lymph nodes, as well as in the epithelium of the bronchial mucosa and alveoli.

Released viral particles penetrate into unaffected cells, blood. With the blood current adenoviruses are entered into the liver, kidneys, spleen, gastrointestinal tract, causing their defeat.

Morphological changes. In patients with adenovirus infection, catarrhal laryngotraheobronchitis is found, often with deep necrotic changes in the epithelial layer of the trachea and bronchi of all calibres. Characteristic is the rejection of the respiratory tract epithelium. Under the epithelium, a serous fluid with an admixture of erythrocytes accumulates. Mononuclear infiltration, giant single-nucleated cells are revealed. Along with changes in the respiratory tract, pronounced shifts in the lung tissue are possible, typical of the giant cell desquamative pneumonia.

Internal organs reveal hemodynamic disorders, dystrophic, necrobiotic and inflammatory changes.

Classification of

I. By form:

II.For the main syndrome:

Hepatitis

III.By the severity of the process:

IV.In the course of the disease:

V. By nature of complications: pneumonia bacterial, otitis, sinusitis, etc.

VI.Mixt infection.

Diagnostics

For etiologic diagnosis of the disease, an immunofluorescence method is used to detect the virus in the nasopharyngeal discharge( epithelial cells).In recent years, an immunochromatographic slide test for the detection of adenovirus in the stool with a sensitivity of 99% and a specificity of 91.6% has been developed in recent years( analysis time is 15 min).

Antibodies to serum adenoviruses

To detect AT to adenoviruses, use of DSC or ELISA is used.

In RBC, the study is performed at the onset of the disease and after 5-7 days, the increase in the AT titer is considered to be diagnostic at least 4-fold in the study of paired sera.

The ELISA method is characterized by high specificity, but low sensitivity. As with RSK, for use in the diagnostic purposes of ELISA, comparison of AT titers in serum samples obtained from patients at the beginning and at the end of the disease is necessary.

The determination of AT titers to adenoviruses is used to diagnose acute respiratory viral infections, assess the intensity of post-vaccination immunity, and diagnose adenoviral infections.

Symptoms of

The incubation period of adenovirus infection is 2-12 days, on average - 4-7 days.

The onset of the disease is acute, but can be gradual.

Adenovirus infection is characterized by a variety of clinical symptoms. Various manifestations of the disease appear consistently. The prevalence of local symptoms of the disease over the general.

Intoxication is moderately expressed, characterized by lethargy, adynamia, decreased appetite, sleep disturbance, and sometimes headache. Muscular and joint pains are possible.

Body temperature can increase gradually, reaching a maximum by the 2-3 day. A wave-like temperature is possible. In some patients, body temperature does not increase.

Since the first days of the disease, the child has seen catarrhal phenomena: rhinitis with abundant serous or mucous discharge, puffiness, hyperemia and granularity of the posterior pharyngeal wall. The mucous membranes of the anterior arch and palatine tonsils are hyperemic. The patient is worried about a cough that quickly acquires a wet character.

A characteristic symptom of an adenovirus infection is conjunctivitis, which can be catarrhal, follicular, pleural. Usually, one eye is first affected, then the conjunctiva of the second eye is involved in the process. The skin of the eyelid is moderately edematous, hyperemic, the conjunctiva of the eye is hyperemic, edematic, granular. It is possible to form a dense grayish-white film on the conjunctiva. Most often the lower eyelid is affected. The film on the eyeball does not spread, it is difficult to separate, very slowly torn away( after 7-14 days).The scleras are injected.

A frequent symptom of adenovirus infection is a mild enlargement of the lymph nodes, mostly submandibular, supernumerary, but possibly other groups. In some patients, mesadenitis develops. Often there is an increase in the liver and spleen.

At the height of clinical manifestations in young children, a liquid stool of enteric character may appear.

Manifestations of adenovirus infection persist for a long time: fever - up to 5-10 days, catarrhal events - up to 10-15 days, conjunctivitis - up to 10-14 days.

Clinic for pharyngoconjunctival fever .The clinical picture of pharyngoconjunctival fever is characterized by a triad:

1) fever;

2) pharyngitis;

3) non-purulent follicular conjunctivitis.

The onset of the disease is acute, with an increase in body temperature to 38-39 ° C, the appearance of symptoms of intoxication. In young children, the onset of the disease can be gradual.

Body temperature on high figures persists for 1-2 weeks, decreases lytically.

Symptoms of catarrhal or catarrhal follicular conjunctivitis occur on the 1-3th day of the disease, followed by the appearance of a dense, white or yellowish color in some patients, which dissolves very slowly.

Catarrhal manifestations from the upper respiratory tract with prevalence of exudative nature of inflammation of the mucosa are clearly pronounced. Attention is drawn to the "granular" pharyngitis. Some children may have a rapidly disappearing island or filmy coating on the tonsils.

Cough at first dry, from the 3rd to 4th day gets wet. There is a pronounced reaction from the lymph nodes. Sometimes the liver is enlarged( 2-3 cm), the spleen( 1-3 cm).

The appearance of the patient is characteristic: the face is pasty, the eyelids are edematous, a small purulent discharge from the eyes, abundant serous-mucous discharge from the nose. Symptoms of tonsillopharyngitis. Tonsillopharyngitis is characterized by a moderate temperature reaction and pronounced changes in the oropharynx. Patients are concerned about sore throat. On examination, the hyperemia and granularity of the arches, the tongue, the posterior pharyngeal wall are found. On tonsils - thin filmy overlay. An increase in submandibular lymph nodes is revealed.

Clinical manifestations of mesadenitis. Mesenenites of adenovirus etiology are characterized by acutely occurring paroxysmal pains in the navel or right iliac region. Symptoms of irritation of the peritoneum are possible. Characteristic increase in body temperature to febrile digits. Catarrhal manifestations are moderately expressed.

Catarrh of the upper respiratory tract. Qatar of the upper respiratory tract is the most frequent clinical variant of adenovirus infection. Characterized by an increase in body temperature for 3 to 4 days, mild symptoms of intoxication and bright catarrhal phenomena in the form of rhinitis, laryngitis, tracheobronchitis.

The onset of the disease is acute, with fever to febrile, but a gradual increase in temperature from subfebrile to febrile is possible. In some patients, the course of the disease is febrile.

Since the first day of the illness, pharyngitis has developed.

Lesion of the laryngeal mucosa, as well as the formation of stenosing laryngitis, is observed quite rarely and mainly in patients aged 1-3 years. Stenosis of the larynx of adenovirus etiology is characterized by development in the first day of the disease and rapid positive dynamics.

Involvement of bronchial infection in the infectious process is observed quite often, but mainly in patients of the first years of life. An expiratory dyspnea, a frequent, wet, persistent cough is recorded. When examining patients over pulmonary fields, a tympanic hue of percussion sound is detected, dry and wet large and medium bubbling rales. Auscultative changes are not always apparent from the first days of the disease, but they are very resistant.

It is possible to develop obliterating bronchiolitis, in which a widespread but often unilateral lesion of the epithelium of bronchioles followed by a granulomatous reaction and obliteration of their lumen. Clinic of the initial period of obliterating bronchitis is the same as acute. The child is marked by an expiratory dyspnea of ​​an expiratory nature, participation in the act of respiration of the auxiliary musculature, the retraction of compliant places of the thorax, perioral cyanosis. Along with respiratory failure, intoxication is observed. When percussion of the lungs is determined tympanitis, with auscultation - an elongated breath, an abundance of diffuse finely bubbling crepitating or raznichalibnyh wheezing both on inspiration and exhalation.

The development of obliterating bronchitis is accompanied by increasing respiratory insufficiency. Auscultative changes persist for 5-6 weeks or more, becoming permanent. Intoxication and temperature increase are observed for a long time.

X-rays with obliterating bronchiolitis are typical for the appearance of areas of reduced pneumatization, alternating with air, and in the future - the formation of the phenomenon of "one-sided super-transparent lung"( MacLeod's syndrome).

In the bronchogram with bronchitis of adenovirus etiology, a high content of neutrophilic granulocytes, cells of degenerative epithelium, as well as cells of deep layers of the bronchial wall( basal and goblet) is found. The recovery period of bronchocytogram indices for adenovirus infection is longer than in other infections, and in some children they do not normalize by the time of clinical recovery.

Clinic of keratoconjunctivitis .Keratoconjunctivitis is a fairly rare form of adenovirus infection.

The onset of the disease is acute, with fever to febrile numbers, with the appearance of symptoms of intoxication, pain in the eyes, photophobia. From the first days, conjunctivitis of one eye develops, after 3-7 days - the second, on the 10-12th day joins the opacity of the cornea.

The course of the disease is long, but benign: after 3-4 weeks, a full recovery comes.

Clinical Symptoms of Adenovirus Infection:

Features of adenovirus infection in newborns and children of the first year of life. Due to passive immunity received from the mother, newborns are rarely ill with adenovirus infection. But if the disease develops, it is characterized by a subfebrile temperature, no symptoms of intoxication, nasal congestion, and a rare cough. The child is restless, sleep is disturbed due to difficulty in nasal breathing.

Diarrheal syndrome, bronchitis with obstructive syndrome, interstitial pneumonia often develop.

The disease is severe, and the development of an unfavorable outcome is possible with the attachment of a bacterial infection.

Treatment and prevention as in ASVI