What is pneumococcus (Streptococcus pneumoniae)?

From the Guidelines

Pneumococcus, or Streptococcus pneumoniae, is a gram-positive bacterium that commonly colonizes the human respiratory tract but can cause serious infections, and the most recent guidelines recommend vaccination with pneumococcal vaccines and treatment with antibiotics such as amoxicillin, ceftriaxone, or fluoroquinolones, depending on the severity of the infection and the patient's age and health status 1. The bacterium is responsible for pneumonia, meningitis, bacteremia, sinusitis, and otitis media, particularly in children under 5, adults over 65, and immunocompromised individuals. Prevention primarily involves vaccination with pneumococcal vaccines: PCV13 (Prevnar 13) for children and high-risk adults, and PPSV23 (Pneumovax) for adults over 65 and those with certain medical conditions. For treatment of pneumococcal infections, antibiotics are essential, with penicillin being the traditional first-line therapy, though resistance has emerged in many regions. Alternative antibiotics include amoxicillin (high-dose 90 mg/kg/day divided twice daily for 10 days for otitis media), ceftriaxone, fluoroquinolones, or vancomycin for resistant strains, as recommended by the most recent guidelines 1. Some key points to consider in the treatment of pneumococcal infections include:

• The use of amoxicillin as the preferred oral treatment for pneumococcal pneumonia involving susceptible strains 1.
• The use of cefotaxime or ceftriaxone as the preferred parenteral agents for treatment of pneumococcal pneumonia without meningitis for strains with reduced susceptibility to penicillin but with MICs of cefotaxime or ceftriaxone of ≤2 mg/mL 1.
• The importance of considering the patient's age, health status, and severity of infection when selecting an antibiotic regimen 1. Pneumococcus spreads through respiratory droplets, and its virulence stems from its polysaccharide capsule that helps it evade the immune system and its ability to produce toxins that damage host tissues. The most recent study on the use of 13-valent pneumococcal conjugate vaccine and 23-valent pneumococcal polysaccharide vaccine among adults aged ≥65 years provides updated recommendations for the prevention of pneumococcal disease in this population 1. Overall, the management of pneumococcal infections requires a comprehensive approach that includes prevention, diagnosis, and treatment, and the most recent guidelines and studies provide important guidance for healthcare professionals in this area.

From the Research

Pneumococcus Overview

• Pneumococcus, also known as Streptococcus pneumoniae, is a common and serious health problem that can be prevented by the pneumococcal vaccine 2.
• The first pneumococcal vaccine was approved in 1977 and contained 14 polysaccharide antigens, while an improved vaccine introduced in 1983 included 23 polysaccharide antigens 2.

Risk Factors and Vaccination Recommendations

• Children at risk for pneumococcal pneumonia, such as those with chronic disease, should receive the 13-valent conjugated vaccine 2.
• Adults at risk for pneumococcal pneumonia, including those over 65 years of age and those with chronic disease, should receive the 23-polysaccharide vaccine 2.
• Immunosuppressed patients of any age should receive both vaccines 2.
• Children with functional or anatomic asplenia, human immunodeficiency virus infection, and other predisposing conditions are at high risk of invasive pneumococcal infection and should receive pneumococcal conjugate vaccine (PCV7) 3.

Treatment and Prevention

• Susceptible pneumococci causing uncomplicated, noninvasive childhood infections should be treated with a narrow-spectrum antimicrobial, such as amoxicillin 4.
• Severely ill patients and those with infections caused by resistant pneumococci may be treated with parenteral antibiotic agents based on the isolate’s susceptibility and the site of the infection 4.
• Two vaccines, PPSV23 and PCV13, are highly effective in preventing pneumococcal infection 5.
• The most appropriate antibiotics for treating pneumococcal infection are macrolides, beta-lactams, and quinolones 5.

Epidemiology and Burden of Disease

• Pneumococcal infections are the most common invasive bacterial infections in children in the United States, with the incidence peaking in children younger than 2 years 6.
• Children with certain underlying conditions, such as sickle cell disease, are at higher risk of pneumococcal infection and should receive continuous penicillin prophylaxis to reduce the risk of disease 6.
• The pneumococcal conjugate vaccine has reduced the burden of pneumococcal disease, but continues to affect the epidemiology of pneumococcal infections caused by nonvaccine serotypes and antibiotic-resistant pneumococci 4.