Epidemiology of emerging pneumococcal drug resistance: implications for treatment and prevention

Drug-resistant Streptococcus pneumoniae infection are becoming increasingly common throughout the world. These strains pose new challenges in the treatment of suspected pneumococcal infections, and they highlight the importance of limiting selection for resistant strains through judicious antibiotic use and preventing infection by immunization of persons at high risk. The clinical impact of drug-resistant S. pneumoniae infection has not been fully defined, but anecdotal reports suggest that outcome is poor for persons with drug-resistant pneumococcal meningitis. The American Academy of Pediatrics has recommended adding vancomycin to the treatment of suspected pneumococcal meningitis cases until the results of culture and susceptibility testing are available. Additional data are needed to determine the optimal empiric antibiotic regimen for nonmeningeal invasive pneumococcal infections. A 23-valent pneumococcal capsular polysaccharide vaccine can prevent many drug-resistant and susceptible invasive pneumococcal infections. The vaccine is recommended in the United States for persons at increased risk of pneumococcal infection due to certain medical conditions and for all persons > or = 65 years old. Vaccine efficacy for immunocompetent persons > or = 65 years is 75%. However, the vaccine is underutilized, and a substantial reduction in the morbidity and mortality associated with invasive pneumococcal infections is unlikely until the vaccine is used more widely among persons at risk for disease.