Pseudomonas carrier rates of patients with cystic fibrosis and of members of their families.

The majority (86.6%) of patients with cystic fibrosis were found to be 
carriers of Pseudomonas aeruginosa. None of them, however, carried P. aeruginosa 
in their nares. In contrast, none of the non-CF family members 
of the patients with CF were carriers of P. aeruginosa. For 
example, only 4 of 468 cultures from skin, throat, and nares 
of the family members were positive for P. aeruginosa. Isolations of 
P. aeruginosa from the same CF patients were often of the 
same pyocine type. No specific pyocine type of P. aeruginosa was 
predominant in patients with CF. Isolations of P. aeruginosa from siblings 
with CF may or may not be of the same pyocine 
type as that of the family proband. Colonization of a patient 
with CF by P. aeruginosa is not a threat to the 
non-CF members of the family. 