Abstract and Introduction
Abstract
Purpose of review: To discuss the role of human rhinoviruses (HRVs) in early childhood wheezing illnesses and how HRVs contribute to the development of childhood asthma.
Recent findings: Advanced molecular diagnostics have identified HRVs as pathogens frequently causing wheezing illnesses in infants and young children. Wheezing during HRV infection in early life identifies children at particularly high-risk of asthma development. Plausible mechanisms by which HRV could cause airway damage, promote airway remodeling, and lead to asthma development have recently been identified.
Summary: HRV is a significant source of morbidity in infants and young children. The present review identifies mechanisms by which HRV lower respiratory tract infection, particularly in a susceptible host, could promote the development of childhood asthma. Further studies are needed to elucidate the mechanisms underlying the link between HRV wheezing in early childhood and subsequent asthma development, with the critical goal of identifying novel therapeutic and prevention strategies for both early childhood wheezing and asthma.
Introduction
Wheezing illnesses associated with viral respiratory infections commonly herald the development of asthma in early childhood. Whether these infections are causal in asthma development is controversial. Through the years, the role of respiratory syncytial virus (RSV) bronchiolitis during early childhood in asthma development has been extensively scrutinized. There is evidence to show that children who wheeze with RSV infections during the first few years of life, particularly those who are hospitalized, are at increased risk of childhood asthma. With the development of molecular viral diagnostics, much has been learned over the past decade with respect to the role of previously undiscovered or underappreciated viruses as early childhood respiratory pathogens. Perhaps most significantly, human rhinoviruses (HRVs) have been recognized as an extremely common cause of wheezing illnesses in early childhood and beyond. In addition, wheezing during HRV infections has been strongly linked to subsequent asthma development. The present review will focus on the mechanisms underlying host-susceptibility to HRV infections and the role HRVs play in early childhood wheezing and asthma development.