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Pneumococcal Infections


Larry M. Bush


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Topic Resources
  • Pneumococcal bacteria are dispersed in the air when infected people cough or sneeze.



  • Young children are routinely vaccinated against these infections, and vaccination is also recommended for all people 65 years of age and older and all people at high risk.

  • Penicillin or another antibiotic is usually effective treatment.



  • Inhale infected droplets dispersed by sneezing or coughing

  • Come in close contact with an infected person

Spread is more likely among certain populations of people, such as military personnel and homeless people. Spread is also more likely to occur among self-contained groups of people, such as people who live, stay, or work in nursing homes or long-term care facilities, hospital wards, prisons, military bases, universities or schools, shelters for the homeless, or day care centers.

Risk factors

Certain conditions increase the risk of developing and the severity of pneumococcal infections:


Symptoms and Diagnosis


Most pneumococcal infections occur in the

Pneumococcal pneumonia

Often, symptoms of pneumococcal pneumonia Overview of Pneumonia Pneumonia is an infection of the small air sacs of the lungs (alveoli) and the tissues around them. Pneumonia is one of the most common causes of death worldwide. Often, pneumonia is the final... read more Overview of Pneumonia begin suddenly. People have fever, chills, a general feeling of illness (malaise), shortness of breath, and a cough. The cough brings up sputum that is rust-colored.

Commonly, sharp, stabbing chest pains occur on one side. Deep breathing and coughing make the pains worse. In about 40% of people, fluid accumulates between the layers of tissue that cover the lungs (called pleural effusion Pleural Effusion Pleural effusion is the abnormal accumulation of fluid in the pleural space (the area between the two layers of the thin membrane that covers the lungs). Fluid can accumulate in the pleural... read more Pleural Effusion ). Pleural effusion may contribute to chest pain and make breathing difficult.

Chest x-rays are taken to look for signs of pneumonia. Doctors take a sample of sputum and examine it under a microscope. A sample of sputum, pus, or blood may be sent to a laboratory to grow (culture) bacteria. Pneumococcal bacteria are easily identified. They are also tested to see which antibiotics are effective (a process called susceptibility testing Testing of a Microorganism's Susceptibility and Sensitivity to Antimicrobial Drugs Infectious diseases are caused by microorganisms, such as bacteria, viruses, fungi, and parasites. Doctors suspect an infection based on the person's symptoms, physical examination results,... read more ).

Pneumococcal meningitis


Pneumococcal meningitis may lead to complications, such as

  • Hearing loss (in up to 50% of people)

  • Seizures

  • Learning disabilities

  • Mental dysfunction


Pneumococcal otitis media

Pneumococcal bacteria causes about 30 to 40% of all cases of otitis media in children. Pneumococcal otitis media commonly recurs.

The diagnosis of pneumococcal otitis media is usually based on symptoms and results of a physical examination. Cultures and other diagnostic tests are usually not done.

Pneumococcal sinusitis

Pneumococcal sinusitis Sinusitis Sinusitis is inflammation of the sinuses, most commonly caused by a viral or bacterial infection or by an allergy. Some of the most common symptoms of sinusitis are pain, tenderness, nasal congestion... read more most commonly affects the sinuses located in the cheekbones (the maxillary sinuses) and the sinuses located on either side of the nasal cavity (the ethmoid sinuses). The infection causes sinus pain and pus discharged from the nose. The infection may become chronic. The infection may extend into the skull and cause complications such as the following:

A doctor bases the diagnosis of sinusitis on the typical symptoms. A computed tomography (CT) scan is done when people have symptoms of complications or when people have chronic sinusitis.

Pneumococcal bacteremia

If bacteremia is suspected, doctors usually take a sample of blood so they can try to grow (culture) the bacteria in the laboratory and identify it.

Despite antibiotic treatment, pneumococcal bacteremia often causes death, especially in older people, people who have disorders that weaken their immune system, or people who have no spleen.

Prevention of Pneumococcal Infections

Pneumococcal infections can be prevented with vaccines and, for certain people, antibiotics.


Two types of pneumococcal vaccines are available:

The vaccine schedules vary depending on the person's age and medical conditions.

PCV13 is recommended for

PPSV23 is recommended for



Treatment of Pneumococcal Infections

  • Antibiotics


Pneumococci that are resistant to penicillin are becoming more common. Thus, other antibiotics, such as ceftriaxone, cefotaxime, fluoroquinolones (such as levofloxacin), vancomycin, lefamulin, or omadacycline, are often used. Vancomycin is not always effective against meningitis caused by pneumococci. Thus, people with meningitis are usually given ceftriaxone or cefotaxime, rifampin, or both, as well as vancomycin.

More Information


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