It has been recorded that since 1950 the rates of Asthma in children has increased alarmingly to 20% in western countries. Here the narrow airways from nose to the lungs are associated. A child suffering from asthma have sensitivity to some triggers like viral infections, allergies and irritating particles in the air. Study of 319 children showed that 3 months old infants who have risk of asthma had lower four types of gut bacteria that could have immune them from the asthma. They typically have these bacteria but some can not : Faecalibacterium, Lachnospira, Veillonella, Rothia.
In humans we are subjected to trillions of bacteria that are actually vital for her healthy body system. But moving towards a more hygienic life style we destroy are immune systems to some extent.