We describe a study of the epidemiology of Pseudomonas aeruginosa (PA) infection in a group of adults with cystic fibrosis who attended a week-long summer camp in the U.K. Sputum samples were collected from 17 patients at the beginning and at the end of the holiday period. Examination of previous sputum samples had identified 11 patients who were chronically colonised with PA. They shared accommodation during the holiday. The sputum samples from these 11 patients were analysed so as to identify the strains of PA by their genotypic characters. All patients were colonised by unique strains before the beginning of the holiday, with the exception of two pairs of patients whose isolates were indistinguishable. After the holiday, eight of the 11 patients harboured strains of the same genotype as was found in their pre-holiday specimens. In three patients, a strain present post-holiday was different from that found in the pre-holiday specimen. In addition, in the case of one patient, two different genotypes were found in the pre-holiday specimen, only one of which was present after the holiday. Evidence of cross-infection of PA during the holiday was not found. Even so, evidence of person-to-person transmission of PA both within the hospital environment and through social contact is presented and discussed.
Bibliographical noteFunding Information:
(D. L. Smith and L. B. Gumery were supported by the Cystic Fibrosis Trust. L. M. Dalla Costa was supported by the British Council.)