The 3 years old child complains on cough which increases gradually. On the 12th day objectively the temperature is 37,10С, the skin is pale. The mouth mucosa is pale-pink. On the tongue ligamentum there is a small ulceration. Cough attacks are seen up to 20 per day, which are characterized by a serial of cough elements, followed by loud breathing in; the attack is finished with expectoration of lucid thick mucus. In the lungs there are coarse breezing sounds, dry rales, sometimes moist. On X-ray: horizontal ribs, increased inflation of the lungs, widened bronchial picture. In the blood: leukocytosis - 23х109/l, eosinophils -1%, bands -3%, segments -23%, lymphocytes -70%, monocytes -3%, ESR - 3 mm/h. What is the most probable preliminary diagnosis?
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