TABLE 1.

RATIONALE FOR MICROBIAL MANIPULATION FOR ASTHMA PREVENTION

1. A transmissible agent is involved in the pathogenesis of asthma.

2. This agent is a respiratory virus, most likely an HRV.

3. Some strains of HRV are more “asthmagenic” than others.

4. The effectiveness of immune function determines whether infection with an “asthmagenic” strain induces asthma.

5. Effectiveness of immune function increases during infancy, but more slowly in children predisposed to atopy.

6. The rate of maturation of immune function is affected by microbial exposure in infancy, especially through the GI tract.

7. Early microbial exposure can be achieved safely by feeding infants “probiotics.”

Definition of abbreviations: GI = gastrointestinal; HRV = human rhinovirus.