Introduction
Wheeze is the musical continuous sound produced by oscillations in any
critically narrowed airways, and heard mostly on expiration. It is
common in preschool age, about half of all children will experience an
episode of wheezing by their sixth birthday.
Asthma is usually characterized by cough, wheeze, chest tightness and
fast breathing. It is a significant global health issue and affects both
children and adults. The prevalence is on the increase, especially in
LMIC. Studies from different populations have revealed the key role
influencing the progression from preschool wheezing to childhood asthma.
Recurrent wheezing is four or more episodes in the preceding year and
has a spectrum of phenotypes and with heterogeneous features. Phenotypes
of wheezing were proposed to facilitate the identification of young
children who are at risk of subsequent development of asthma. The
epidemiology and environmental determinants of recurrent wheezing and
asthma are discussed.