pneumococcal disease
Any infection caused by Streptococcus pneumoniae (pneumococcus).
It is a Gram-positive, spherical bacteria, alpha-hemolytic under aerobic conditions or beta-hemolytic under anaerobic conditions. They are non motile, usually found in pairs (diplococci) and do not form spores.
It resides asymptomatically in healthy carriers typically colonizing the respiratory tract, sinuses, and nasal cavity.
However, in susceptible individuals with weaker immune systems (e.g. young children, elderly), it may become pathogenic and spread to other locations to cause disease.
(Range of infection)
• ear infection
• sinus infection
• pneumonia (infection of lung parenchyma)
• bloodstream infection
(Pneumococcal diseases other than pneumonia)
• bronchitis
• rhinitis
• sinusitis
• otitis media
• conjunctivitis
• cellulitis: Skin infection that causes redness, swelling, and pain.
• meningitis
• brain abscess
• pericarditis
• endocarditis
• sepsis
• septic arthritis
• osteomyelitis
• peritonitis
(Transmission)
• Direct contact, person-to-person via respiratory droplets.
• Autoinoculation in the upper respiratory tracts.
• Neonatal infections.
(Diagnosis)
ear and sinus infections:
• history
• physical exam
pneumonia:
• urine test: Detects its antigen in the urine within 15 minutes.
meningitis, sepsis:
• Samples of cerebrospinal fluid (by lumbar puncture) or blood.
• Growing the bacteria in a laboratory to identify the specific type of bacteria for the right treatment.
(Prevention)
• pneumococcal vaccine: A previous pneumococcal infection will not protect you from reinfection. But it not perfect and there is still a chance to develop pneumococcal disease after vaccination.
• influenza vaccine: Having the flu increases the likelihood of getting pneumococcal disease.
• Generally, people do not develop pneumococcal disease after exposure to someone with a pneumococcal infection, so prophylaxis or preventive antibiotics is not recommended.
(Treatment)
Some pneumococcal bacteria have become resistant to certain antibiotics.
1. "Broad-spectrum" antibiotics until results of antibiotic sensitivity testing are available.
2. "Narrow-spectrum" antibiotic.