The Association of Early Life Viral Respiratory Illness and Atopy on Asthma in Children: Systematic Review and Meta-Analysis

Abstract

Background: The interaction between early life viral respiratory illness and atopy in the genesis of asthma has been widely discussed in the literature as the “two-hit hypothesis.” Objective: To synthesize evidence regarding the association of childhood viral respiratory illness and atopy in the development of persistent wheezing and asthma. Methods: A systematic review was performed, according to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Human studies investigating early life associations between atopy and viral respiratory illness with outcomes of asthma and wheezing were included. Meta-analysis was performed to investigate the association of v..