KEYWORDS:
invasive pneumococcal infection, pneumococcal polysaccharide vaccine

BACKGROUND:
Invasive pneumococcal infection has a 30-40% case-fatality rate among elderly persons but is preventable with pneumococcal polysaccharide vaccine (PPV) use.

OBJECTIVE(S):
The New Jersey Department of Health and Senior Services investigated an outbreak of invasive pneumococcal infection among residents of a New Jersey nursing home in April 2001 to characterize risk factors, determine why the outbreak may have occurred, and implement control efforts.

METHOD(S):
We defined a case-patient as a resident of the nursing home who was hospitalized with febrile respiratory illness with radiographic findings consistent with pneumonia and sputum specimens positive for diplococci or blood cultures positive for S. pneumoniae. Blood culture isolates were serotyped. Two unmatched controls per case-patient were selected randomly from remaining residents without respiratory symptoms. To investigate compliance with state regulations requiring nursing homes to offer PPV to eligible residents, 853 long-term care facilities (LTCFs) statewide were surveyed.

RESULT(S):
The 9 case-patients had a median age of 86 years (range 78-100 years); controls had a median age of 86 years (range 58-95 years). No cases versus 9 (50%) controls received PPV prior to the outbreak (OR=0; CI 0, 0.7). Recent antibiotic use, pneumonia history, and physical functioning were not associated with illness. Illness attack rate among all nonvaccinated residents was 16% versus 0 among vaccinated residents. Serotype 14 S. pneumoniae, which is included in PPV, was isolated from blood cultures of 7 case-patients. Of 361 (42%) LTCFs that replied to the survey, 28 (8%) did not comply with state immunization regulations.

CONCLUSIONS(S):
Outbreaks of pneumococcal infection occur in LTCFs with low vaccine coverage. Implementing standing orders programs, enforcing regulations, documenting vaccinations, and providing education may increase coverage among nursing home residents.

LEARNING OBJECTIVES:
To underscore the importance of providing PPV to nursing home residents and identify strategies to improve vaccine coverage.