Classification: ICD-9 041.2; ICD-10 A40.3
Syndromes and synonyms: None.
Agent: Streptococcus pneumoniae (pneumococcus), an encapsulated Gram-positive bacterium, with >90 serotypes based on capsular polysaccharide antigens. Approximately 23 serotypes are responsible for 90% if the infections in the developed world.
Reservoir: Healthy humans can carry S. pneumoniae in their upper respiratory tract.
Transmission: Direct person-to-person transmission between close contacts by droplet spread or direct oral contact; through objects contaminated with respiratory secretions.
Incubation period: 1 to 3 days.
Clinical findings: Depends on the type of infection and severity. S. pneumoniae is an important cause of severe pneumonia, meningitis, and sepsis. It also is a common cause of otitis media and sinusitis. It can cause deep-seated infections involving any organ in a disseminated disease.
Diagnostic tests: Recovery of S. pneumoniae