Bronchiolitis is characterized by bronchial epithelium necrosis, caused by the virus, increased mucus secretion and cellular infiltration and edema under the mucosa. These changes result in the formation of bronchial obstructive mucosal aggregates and the subsequent collapse of the distal lung tissue. In pneumonia, infiltration is more extensive and the epithelial necrosis may spread to both the bronchi and the alveoli. Due to the small size of the brucellosis, the infants are particularly prone to the obstruction of small airways. Many of the facts of the RSV immunological impairment are probably a factor in the pathogenesis of bronchiolitis due to free solution of RSV (interleukins, leukotrienes, etc.) with potential for inflammation and tissue destruction during infection. RSV contains symptoms of choriza and runny nose and pharyngitis. Coughing may be the first symptoms of an infection in a child at the same time. Shortly after coughing, the baby is suffering from wheezing and chest pain. If the disease is mild, symptoms may not go beyond this stage; subtle quiver of voice and wheezing might be heard out of the lungs of the infected baby. With a different degree of certainty, RSV is a clinical diagnosis of bronchiolitis. The suspicion of developing the disease is based on the basis of the clinical picture, season and the presence of a typical outbreak of the disease at that time. An epidemiologic characteristic is commonly found in older children and other beneficial RSVs are the presence of cold in older members of the family, as they infect adults and cause symptoms. In most cases, bronchiolitis or pneumonia caused by routine tests provide very little useful information. The normal white blood cell count is RSV, and the bacterial culture of the pharynx grows in the pharynx.