The Role of Virus Infections in Early Life and the Development of Asthma: Epidemiology
Respiratory illnesses are a very common cause of consultation in pediatric practice and of hospital admissions in children under the age of 6 years. Infections of the respiratory tract, largely observed as common colds, are the most frequent cause of illness in humans in general. Children in particular go through a series of these viral infections within their ﬁrst years of life. Respiratory syncytial virus (RSV), human rhinovirus, coronavirus, parainﬂuenza virus type 1-3, adenovirus, and inﬂuenza virus type A and B have all been associated with infections of the respiratory tract in children (1-4). In general, any respiratory virus can cause any picture of acute respiratory infection, but certain viruses tend to associate with a particular group of diseases (5).