Interference withHaemophilus influenzaegrowth by other microorganisms

A total of 97 aerobic and facultatively anaerobic bacteria, and 3 Candida albicans, were tested for their ability to inhibit the growth of Haemophilus influenzae. Only strains of Pseudomonas aeruginosa showed any inhibitory effect and all 5 strains tested clearly inhibited the growth of all 10 strains of H. influenzae. The inhibition of H. influenzae. by Ps. aeruginosa may play a role in the establishment of chronic Ps. aeruginosa infections in the respiratory tracts of patients with bronchiectasis and cystic fibrosis (CF).