Patient Presentation
A 2.5 year-old female came to clinic for followup of hospitalization from an outside hospital 2 days after discharge for pneumococcal pneumonia. She had presented with fever, severe cough, and increased work of breathing. She was treated with high flow oxygen and ceftriaxone with improvement after 5 days. She was discharged on oral antibiotics to continue a 10 day course. The mother reported that she remained tired, wasn’t sleeping as well because of the cough, and was drinking but not eating solid foods that well. She was taking her medication. The past medical history was significant for 2 otitis media episodes, a documented influenza infection 1 year prior, and she was unimmunized.
The pertinent physical exam showed a tired appearing female with normal vital signs and oxygen saturation at 96% on room air. She appeared hydrated. HEENT was normal. Her lungs had very coarse breath sounds overall that were decreased on the right side with some crackles. The rest of her examination was normal.
The diagnosis of presumed pneumococcal pneumonia was made. The pediatrician reiterated the importance of finishing all of the antibiotics. He also discussed symptomatic treatment and brought up that when she felt better she could be immunized against pneumococcus and other infectious diseases, and provided some resources again to her mother. Her mother said she would think about it.
Figure 151 – A chest radiograph showing pneumococcal pneumonia.
Discussion
Streptococcus pneumoniae causes invasive or non-invasive disease. Invasive disease examples include bacteremia, meningitis and pneumonia, as well as less commonly septic arthritis, endocarditis, or osteomyelitis. Non-invasive (local) examples include otitis media and sinusitis. Pneumococcal disease causes significant morbidity and mortality world-wide, especially in the young children and older adult age groups. There are more than 100 serotypes with a relatively small number of them causing the majority of human disease. Studies over the last 25 years have shown pneumococcal vaccines (PV) to be effective against invasive and non-invasive diseases. Antibody production is good. Etiology/radiological confirmation of pneumonia shows marked decrease in cases. There is also data that supports PV vaccine as effective against viral lower respiratory tract diseases with the strongest evidence for decreased influenza but also seasonal coronavirus, human metapneumovirus and parainfluenza. This is important as co-infections in the respiratory tract are known to be associated with more severe disease. This could be due to one or more of the following such as decreasing the overall number of PV infections, changes to the PV serotypes, changes in the nasopharyngeal carriage and therefore biome of the individual, or other reasons.
Learning Point
Some of the main differences in the 20- and 23-valent vaccines are which serotypes are used, how they are produced and reduction in nasopharyngeal carriage.
Pneumococcal vaccine development started with a few serotypes and grew over time. Additional serotypes were added based on residual serotype prevalence and geographical distribution.
- 7 valent – 4, 6B, 9V, 14, 18C, 19F, 23F
- FDA approved 2000
- 13 valent – 7 valent + 1, 3, 5, 6A, 7F, 19A
- FDA approved 2010
- 20 valent – 13 valent + 8, 10A, 11A, 12F, 15B, 22F, 33F
- Valences given are for Pfizer manufacturer
- Prevnar® FDA approved in 2023
- Conjugated vaccine (often abbreviated as PCV) with carrier protein diphtheria CRM197 protein
- Does significantly reduce nasopharyngeal carriage
- 23 valent – has slightly different valences as it is produced by Merck with 1, 2, 3, 4, 5, 6B, 7F, 8, 9N, 9V, 10A, 11A, 12F, 14, 15B, 17F, 18C, 19F, 19A, 20, 22F, 23F, and 33F
- Pneumovax® FDA originally approved 1983 and updated in 2021
- Polysaccharide vaccine (often abbreviated as PPSV) with carrier protein non-type Haemophilus influenza (NTHi)
- Does not significantly reduce nasopharyngeal carriage
10-, 15- and 21 valent were, or are available as well. However two of the common ones used in the US currently are 20- and 23-valent. 20- and 23- valent have many additional serotypes that are important in the pediatric age range as well as the adults. PVs are given as intramuscular or subcutaneous injection. They induce IgG antibody production as well as opsonophagocystic activity. Side effects are usually mild to moderate with pain or redness or swelling at the injection site, fever, fussiness, decreased appetite or fatigue.
Vaccine schedules vary. Some children who previously received PV with fewer serotypes may be recommended to be re-vaccinated with higher valent vaccines. These include children who are immunocompromised or have chronic health conditions putting them at higher risk for pneumococcal disease.
Questions for Further Discussion
1. What other diseases are caused by Streptococcus?
2. What are common causes of community acquired pneumonia in your location?
3. What are potential complications of pneumonia?
Related Cases
- Disease: Childhood Immunization | Streptococcal Infections | Pneumonia
- Symptom/Presentation: Cough | Fever and Fever of Unknown Origin
- Age: Toddler
To Learn More
To view pediatric review articles on this topic from the past year check PubMed.
Evidence-based medicine information on this topic can be found at SearchingPediatrics.com and the Cochrane Database of Systematic Reviews.
Information prescriptions for patients can be found at MedlinePlus for these topics: Pneumococcal Infections, Pneumonia and Streptococcal Infections.
To view current news articles on this topic check Google News.
To view images related to this topic check Google Images.
To view videos related to this topic check YouTube Videos.
Gessner BD, Isturiz R, Snow V, Grant LR, Theilacker C, Jodar L. The rationale for use of clinically defined outcomes in assessing the impact of pneumococcal conjugate vaccines against pneumonia. Expert Rev Vaccines. 2021;20(3):269-280. doi:10.1080/14760584.2021.1889376
Shirley M. 20-Valent Pneumococcal Conjugate Vaccine: Pediatric First Approval. Paediatr Drugs. 2023;25(5):613-619. doi:10.1007/s40272-023-00584-9
Sepulveda-Pachon IT, Dunne EM, Hanquet G, et al. Effect of Pneumococcal Conjugate Vaccines on Viral Respiratory Infections: A Systematic Literature Review. J Infect Dis. 2024;230(3):e657-e667. doi:10.1093/infdis/jiae125
Feng S, McLellan J, Pidduck N, et al. Immunogenicity and seroefficacy of pneumococcal conjugate vaccines: a systematic review and network meta-analysis. Health Technol Assess. 2024;28(34):1-109. doi:10.3310/YWHA3079
Author
Donna M. D’Alessandro, MD
Professor of Pediatrics, University of Iowa
Date
April 27, 2026