With the prevalence of asthma increasing each decade, our focus has shifted from treatment to understanding the pathogenesis of asthma so we may develop methods of prevention. With the advent of new bacterial detection techniques, we have the opportunity to examine the infant microbiome (collection of genetic information from organisms that live on humans and pose no threat) prior to the development of wheezing and subsequent asthma. Based on our knowledge that certain bacteria are associated with recurrent wheezing, we believe that an increase in pathogenic bacteria alters the airway epithelium resulting in airway inflammation. This chronic inflammation leads to airway obstruction, resulting in recurrent wheezing. By prospectively following children up to two years we have the opportunity to determine if changes seen in early infancy are established early and persist until 2 years of age. In addition, we propose to determine if the microbiome contributes to airway obstruction and episodes of wheezing with respiratory illness. This study tests the hypothesis that an increase in pathogenic bacteria within the infant airway leads to increased airway inflammation, decreased airway function and ultimately airway obstruction throughout the first one to two years of life.