title: Halting a pneumococcal pneumonia outbreak among United States Marine Corps trainees.
abstract: BACKGROUND
  Streptococcus pneumoniae is the leading cause of bacterial pneumonia in all age groups. Identifying outbreaks of pneumococcal disease and key risk factors may lead to improvements in vaccination and prevention strategies for high-risk groups. A significant outbreak of S. pneumoniae pneumonia that occurred among Marine recruits is reported here.
  
  
  METHODS
  An outbreak was investigated using standard microbiologic procedures and epidemiologic evaluation to define the extent of the outbreak, determine the microbiologic causative agent(s), identify risk factors for the development of disease, and institute preventive measures against further cases of pneumonia among recruits.
  
  
  RESULTS
  Fifty-two cases of radiographically confirmed pneumonia occurred among 3367 Marine recruits over a 2-week period in November 2000. Twenty-five of these cases occurred in a single company of 481 men, with an attack rate of 5.2%. Twelve of the 25 cases were caused by S. pneumoniae, serotypes 4 and 9v. The outbreak rapidly ended following isolation of cases, prophylaxis with oral azithromycin, and administration of the 23-valent pneumococcal vaccine.
  
  
  CONCLUSIONS
  This outbreak of pneumococcal disease occurred in the setting of intense military training and a crowded environment. The use of the pneumococcal vaccine year-round in military trainees and other high-risk populations to reduce pneumococcal disease should be considered.
authors.affiliation: Clinical Investigation Department (KCA), Naval Medical Center San Diego, 34800 Bob Wilson Drive, Suite 5, San Diego, CA 92134-1005, USA. nfcrum@nmcsd.med.navy.mil
authors.forename: Nancy F
authors.initials: NF
authors.lastname: Crum
authors.forename: Mark R
authors.initials: MR
authors.lastname: Wallace
authors.forename: Carla R
authors.initials: CR
authors.lastname: Lamb
authors.forename: Ava Marie S
authors.initials: AM
authors.lastname: Conlin
authors.forename: Dennis E
authors.initials: DE
authors.lastname: Amundson
authors.forename: Patrick E
authors.initials: PE
authors.lastname: Olson
authors.forename: Margaret A K
authors.initials: MA
authors.lastname: Ryan
authors.forename: Ted J
authors.initials: TJ
authors.lastname: Robinson
authors.forename: Gregory C
authors.initials: GC
authors.lastname: Gray
authors.forename: Kenneth C
authors.initials: KC
authors.lastname: Earhart
mesh_terms: D000293:Adolescent; D000328:Adult; D019072:Antibiotic Prophylaxis; D017963:Azithromycin / Q000627:therapeutic use; D002140:California / Q000453:epidemiology; D004196:Disease Outbreaks / Q000517:prevention & control*; D004917:Erythromycin / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008889:Military Personnel; D010401:Penicillin G Benzathine / Q000627:therapeutic use; D022242:Pneumococcal Vaccines / Q000008:administration & dosage; D011018:Pneumonia, Pneumococcal / Q000175:diagnosis / Q000453:epidemiology* / Q000517:prevention & control*; D012307:Risk Factors; D013296:Streptococcus pneumoniae / Q000302:isolation & purification
chemical_list: D022242:Pneumococcal Vaccines; D004917:Erythromycin; D017963:Azithromycin; D010401:Penicillin G Benzathine