Streptococcus pneumoniae, also known as pneumococcus, is a bacterium that is often found in the noses and throats of healthy persons and is spread person-to-person through close contact. Pneumococcus is a common cause of mild illnesses, such as sinus and ear infections, but also causes life-threatening infections such as pneumonia, meningitis, and infections of the bloodstream. Many strains are resistant to antibiotics.
OccurrenceRisk for pneumococcal disease is highest in young children, the elderly, and persons of any age who have chronic medical conditions such as heart disease, lung disease, or diabetes, or conditions that suppress the immune system, such as HIV. Smokers and those in close contact with small children are also at higher risk. Pneumococcal disease is more common in winter months and when respiratory viruses such as influenza are circulating. Outbreaks of pneumococcal disease are not common but can occur in child care centers, nursing homes, or other institutions. In the United States, most deaths from pneumococcal disease occur in older adults, although in developing countries many children die of pneumococcal pneumonia.
Risk to TravellersPneumococcal disease occurs worldwide. Crowded settings or situations with close, prolonged contact with young children may increase the risk of contracting pneumococcal disease while travelling.
Clinical PresentationFever and malaise are typical symptoms for all forms of pneumococcal disease and may be the only symptoms in young children with blood infections.
Patients with pneumonia usually have cough, often with purulent or blood-tinged sputum, and may have shaking chills, shortness of breath, or pleuritic chest pain. Fever and sputum production may be absent in elderly persons with pneumococcal pneumonia.
Patients with pneumococcal meningitis have headache, photophobia, stiff or painful neck, vomiting, lethargy, or decreased consciousness.
Persons with pneumococcal ear infections typically have pain in the infected ear and can have purulent drainage (pus) following perforation of the ear drum.
Sinus infections cause pain over the sinuses or in the teeth.
Prevention VaccinesTwo vaccines are available to prevent pneumococcal disease; the pneumococcal conjugate vaccine (PCV) (Prevnar, Wyeth Vaccines) and the pneumococcal polysaccharide vaccine (PPV) (Pneumovax, Merck). Both vaccines provide protection by inducing antibodies to specific types of pneumococcal capsule; 90 different types of pneumococcal capsule have been identified. The conjugate vaccine protects against the 7 serotypes most common in young children in the United States; the polysaccharide vaccine includes 23 types. Both vaccines are effective at preventing invasive disease; the severe form of pneumococcal disease in which the organism is found in blood, spinal fluid, or other typically sterile bodily fluids. The conjugate vaccine, licensed for use in young children, also prevents some pneumonia and ear infections.
Pneumococcal conjugate vaccineThe pneumococcal conjugate vaccine is part of the routine infant immunisation schedule. Health-care visits to receive travel-related vaccines provide a good opportunity to make sure that all routine vaccines are up to date. The pneumococcal conjugate vaccine is recommended for all children <2>
- Sickle cell haemoglobinopathies,
- functional or anatomical asplenia,
- received or will receive a cochlear implant,
- HIV infection,
- chronic disease, including chronic cardiac and pulmonary disease (excluding asthma), diabetes mellitus, or cerebrospinal fluid leak; and
- immunocompromising conditions, including a) haematologic or other disseminated malignancies; b) chronic renal failure or nephrotic syndrome; c) ongoing immunosuppressive therapy; and d) solid organ transplant.
Pneumococcal conjugate vaccine also should be considered for healthy children 2-4 years of age, especially those 24-35 months old, those attending group child care, and those of African-American, Alaskan Native or Native American descent.
Pneumococcal polysaccharide vaccineThe pneumococcal polysaccharide vaccine is part of the routine adult immunisation schedule, but many adults who should have received the vaccine have not. In 2003, only 62% of adults 
Pneumococcal polysaccharide vaccine (Pneumovax) is recommended for all adults
- chronic cardiovascular disease (e.g., congestive heart failure or cardiomyopathies)
- chronic pulmonary disease (e.g., chronic obstructive pulmonary disease or emphysema, but not asthma)
- diabetes mellitus
- alcoholism
- chronic liver disease (cirrhosis)
- cerebrospinal fluid leaks
- functional or anatomic asplenia
- cochlear implant (or those planning to receive a cochlear implant)
- HIV infection
- multiple myeloma
- immunocompromising conditions, including a) haematologic or other generalised malignancies; b) chronic renal failure or nephrotic syndrome; c) ongoing immunosuppressive therapy; and d) bone marrow or solid organ transplant.
Recommended regimens for use of pneumococcal conjugate vaccine in children <5>
| Age at examination (months) | Vaccination history | Recommended regimen1 | |
|---|---|---|---|
| 2-6 | 0 doses | 3 doses 2 months apart, 4th dose at age 12-15 months | |
| 1 dose | 2 doses 2 months apart, 4th dose at age 12-15 months | ||
| 2 doses | 1 dose 2 months after the most recent dose, 4th dose at age 12-15 months | ||
| 7-11 | 0 doses | 2 doses 2 months apart, 3rd dose at 12-15 months | |
| 1 or 2 doses before age 7 months | 1 dose at 7-11 months, with another dose at 12-15 months (2 months later) | ||
| 12-23 | 0 doses | 2 doses 2 months apart | |
| 1 dose before age 12 months | 2 doses 2 months apart | ||
| 1 dose at 12 months | 1 dose 2 months after the most recent dose | ||
| 2 or 3 doses before age 12 months | 1 dose 2 months after the most recent dose | ||
| 24-59 | Healthy children | Any incomplete schedule | Consider 1 dose 2 months after the most recent dose2 |
| High risk | Any incomplete schedule of <3> | 1 dose 2 months after the most recent dose and another dose 2 months later | |
| Any incomplete schedule of 3 doses | 1 dose 2 months after the most recent dose | ||
1For children vaccinated at <1 src="http://www.medic8.com/images/gte.gif" id="spc-gte" alt="greater than or equal to" align="bottom" width="14" height="11">12 months should be at least 8 weeks apart.
2Providers should consider administering a single dose to unvaccinated, healthy children 24-59 months old, with priority to children 24-35 months old, children who attend group day care centers, children of African-American descent, and children of Alaskan Native or Native American descent not otherwise identified as high risk.
The polysaccharide vaccine should also be given to those 2-64 years of age who are living in settings in which the risk for invasive pneumococcal disease or its complications is increased, such as certain Native American communities (e.g., Alaskan Natives and certain American Indian populations) and residents of nursing homes and other long-term care facilities.
A single dose of pneumococcal polysaccharide vaccine should be given at age 65 years or at the time a high-risk condition is recognised. Children 2-4 years of age with indications for pneumococcal polysaccharide vaccine should receive polysaccharide vaccine at least 2 months after receiving doses of conjugate vaccine. Persons with an indication for polysaccharide vaccine but with unknown vaccination history should receive one dose. A second dose of vaccine should be used for the following groups:
- persons
- persons with sickle cell disease, asplenia, renal disease, haematologic or generalised malignancy, or other immunocompromising condition.
For children <10 src="http://www.medic8.com/images/gte.gif" id="spc-gte" alt="greater than or equal to" align="bottom" width="14" height="11">3 years after the first dose; for older persons, revaccination may be given after 5 years. Because of limited data on the safety of multiple doses and on the duration of protection provided by polysaccharide vaccine, recommendations are for a single revaccination 3-5 years after the initial dose. These recommendations have been misinterpreted as suggesting revaccination every 5 years.
Safety/Side EffectsMild local reactions such as redness, swelling, or tenderness occur in 10%-23% of infants after receipt of conjugate vaccine. Larger areas of redness or swelling or limitations in arm movement may occur in 1%-9%. For pneumococcal polysaccharide vaccine, mild, local side effects occur in approximately half of vaccine recipients and are more common after revaccination. Local reactions usually resolve by 48 hours after vaccination. More severe local reactions are rare. After conjugate vaccine, low-grade fever can occur in up to 24% of children and fever >102.2�F may occur in up to 2.5%. Systemic symptoms, including myalgias and fever, are rare after polysaccharide vaccine.
Precautions and contraindicationsConjugate vaccine is contraindicated for children known to have a hypersensitivity to any component of the vaccine. Health-care providers may delay vaccination of children with moderate or severe illness until the child has recovered, although minor illnesses, such as mild upper-respiratory tract infection with or without low-grade fever, are not contraindications. Revaccination with pneumococcal polysaccharide vaccine is contraindicated for persons who had a severe reaction (e.g., anaphylactic reaction or localized arthus-type reaction) to the initial dose. Data are limited on the safety of pneumococcal polysaccharide vaccine during the first trimester of pregnancy.
Additional Preventive MeasuresPersons who smoke cigarettes can reduce their risk of pneumococcal disease by stopping smoking. In addition, improving control of chronic conditions that are predisposing factors for pneumococcal disease, such as diabetes and HIV, may reduce risk. Chemoprophylaxis is not routinely recommended. Daily penicillin prophylaxis for children with sickle-cell haemoglobinopathy is recommended beginning before 4 months of age. How long to continue prophylaxis is somewhat controversial. However, children with sickle-cell anaemia who had taken prophylactic penicillin for prolonged intervals but who had not had a severe pneumococcal infection or a splenectomy have stopped prophylactic penicillin therapy at 5 years of age without increased incidence of pneumococcal bacteremia or meningitis. Penicillin prophylaxis is also used for asplenic persons.
TreatmentPneumococcal disease of all types is usually treated with antibiotics. Mild forms such as uncomplicated ear or sinus infections in healthy persons may resolve without treatment. More serious forms of pneumococcal disease, such as bloodstream infections and pneumonia, require antibiotics and often require hospitalization and intravenous antiobiotics. Pneumococcal meningitis always requires hospitalization and intravenous antibiotics. Because pneumococcal disease is endemic worldwide, care from a physician specializing in travel or tropical medicine is not required.
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