Intended for healthcare professionals

Research Article

Resistance of clinical isolates of Haemophilus influenzae in United Kingdom 1986.

Br Med J (Clin Res Ed) 1987; 295 doi: (Published 18 July 1987) Cite this as: Br Med J (Clin Res Ed) 1987;295:176
  1. M Powell,
  2. C Koutsia-Carouzou,
  3. D Voutsinas,
  4. A Seymour,
  5. J D Williams
  1. Department of Medical Microbiology, London Hospital Medical College.


    Between 1 January and 31 March 1986, 2434 strains of Haemophilus influenzae collected from 23 laboratories in the United Kingdom were examined. With the same criteria as previous studies in 1977 and 1981 the prevalence of resistance was: ampicillin 7.8% (6.2% beta-lactamase producers and 1.6% non-producers), tetracycline 2.7%, chloramphenicol 1.7%, trimethoprim 4.2%, and sulphamethoxazole 3.5%. of the 87 capsulated strains, 15 produced beta-lactamase, nine were resistant to ampicillin but did not produce beta-lactamase, and two strains, one of which produced beta-lactamase, were resistant to chloramphenicol and tetracycline. Since 1977 the prevalence of resistance to ampicillin, chloramphenicol, and trimethoprim has increased significantly. During 1981-6 strains resistant to ampicillin but not producing beta-lactamase and strains resistant to trimethoprim have significantly increased.