title: Epidemiology of penicillin-resistant pneumococci in a Merseyside Health District over a 14-year period.
abstract: OBJECTIVE
  To determine the prevalence and epidemiology of penicillin-resistantStreptococcus pneumoniae isolates in the St Helens and Knowsley Health District of Merseyside.
  
  
  METHODS
  Penicillin-resistant pneumococci were isolated from clinical samples taken from 549 patients between January 1987 and December 2000. Patient profile, bacterial serotype and resistance patterns were analysed.
  
  
  RESULTS
  Between January 1987 and December 2000, the prevalence of penicillin-resistant pneumococci increased from 1.4% to a peak of 12.9% in 1997, subsequently falling to 8.9%. High-level penicillin resistance was found in 243 (44.3%) of the isolates. Two hundred and eighty isolates were from children (mean age 2.2 years), of whom only 25% were clinically infected. Two hundred and sixty nine isolates were from adults (average age 68.4 years) of whom 88% were infected. Over 65% of isolates were community acquired with 53% of patients having received antibiotics in the 3 months prior to their first isolate. Twenty six per cent of patients had underlying disease of the respiratory tract. The changing evolution of serotypes over the 14 years of the study was associated with changes in sensitivity patterns. Serotype 9 was the most common serotype (36%).
  
  
  CONCLUSIONS
  The study demonstrates the evolution of penicillin resistance in the patient population of this District over the past 14 years.
authors.affiliation: Department of Microbiology, Whiston Hospital, Prescot Merseyside L35 5DR, UK.
authors.forename: M S
authors.initials: MS
authors.lastname: Vardhan
authors.forename: K D
authors.initials: KD
authors.lastname: Allen
mesh_terms: D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000494:pharmacology / Q000627:therapeutic use; D002675:Child, Preschool; D004196:Disease Outbreaks; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D010403:Penicillin Resistance; D010406:Penicillins / Q000494:pharmacology*; D011008:Pneumococcal Infections / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology*; D012621:Seasons; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000187:drug effects* / Q000502:physiology; D013997:Time Factors; D006113:United Kingdom
chemical_list: D000900:Anti-Bacterial Agents; D010406:Penicillins