streptococcus pneumoniae, or pneumococcus, are gram positive bacteria forming chains, responsible for various infections

streptococcus pneumoniae pneumococcus bacteria infection disease pneumonia meningitis otitis media respiratory illness microorganism pathogen microbiology healthcare medical biology health microscopic gram positive diplococci chains morphology cell organism infectious contagious symptom diagnosis treatment antibiotic resistance prevention vaccine immunization risk complication inflammation lung ear brain sinus blood sepsis bacteremia immune system