Molecular epidemiology of unrelated clusters of multiresistant strains of haemophilus influenzae

Three epidemiologically unrelated clusters of Haemophilus influenzae resistant to ampicillin, chloramphenicol, and tetracycline were studied. The biotypes and cell-envelope protein patterns were determined for 17 nonencapsulated strains, 6 from Dundee and 11 from Cheltenham, and for 6 type b encapsulated strains from Guildford. After mobilization by conjugation, large 32- to 36-MDa plasmids were purified from all the strains. The restriction fragment patterns of the plasmids were determined by ethidium bromide staining of digested purified plasmid or by Southern hybridization of digested total cellular DNA of the parent strains, probed with purified plasmid. Evidence is presented for a chromosomal location of the plasmids in the parent strains, the spread in nature of a plasmid between distinguishable strains of H. influenzae, the person-to- person spread of a strain within a cluster, and a high degree of sequence homology between distinguishable plasmids, implying their close relatedness. © 1992 The University of Chicago

Emergence of pneumococcal 19A empyema in UK children

<p>Introduction: Invasive pneumococcal disease due to serotype 19A has become a major concern, particularly in the USA and Asia. We describe the characteristics of pneumococcal serotype 19A related empyema and changes in its incidence in the UK.</p> <p>Methods: Data from paediatric empyema patients between September 2006 and March 2011 were collected from 17 respiratory centres in the UK. Pneumococcal serotypes were identified as part of the Health Protection Agency enhanced paediatric empyema surveillance programme.</p> <p>Results: Four serotypes accounted for over 80% of 136 cases (Serotype 1 : 43%, 3 : 21%, 7 : 11% and 19A:10%). The incidence of empyema due to serotype 19A quadrupled from 0.48 (0.16–1.13) cases per million children in 2006/2007 to 2.02 (1.25–3.09) in 2010/2011. Severity of disease was significantly increased in children with 19A infection when compared to other serotypes.</p> <p>Conclusions: The incidence of empyema due to pneumococcal serotype 19A infection has increased significantly and is associated with substantial morbidity.</p&gt