Pneumococcal polysaccharide vaccine

Pneumococcal polysaccharide vaccine (PPSV), is a vaccine used to prevent Streptococcus pneumoniae (pneumococcus) infections such as pneumonia and septicaemia. Pneumovax 23, manufactured by Merck, is the currently licensed PPSV. PPSV is not the same vaccination as the pneumococcal conjugate vaccine (PCV) that is routinely administered to infants in the US, Canada, and the UK.^[1] See further under Children, below.

Indications

In the United Kingdom, PPV is recommended (as a part of routine vaccination schedules) for those over the age of 65, and also for both children and adults in special risk categories:

• Serious breathing problems, including Asthma and COPD
• Serious heart conditions, such as Congestive heart failure
• Severe kidney problems
• Long term liver disease
• Diabetes requiring medication
• Immunosuppression due to disease (e.g. HIV/AIDS or lupus) or treatment (e.g. chemotherapy or radio therapy, long-term steroid use, and problems with the spleen (asplenia), either because the spleen has been removed (splenectomy) or does not work properly (for example, due to sickle cell disease).

In the United States, PPSV is recommended for adults 65 years of age or older, adults with serious long-term health problems, smokers, and children older than 2 years with serious long-term health problems.^[2] The World Health Organization recommendations are similar. The WHO does not recommend use of PPV in routine childhood immunization programs.^[3]

Risks

Approximately half of people who receive PPSV experience pain and soreness at the vaccination site. Less than 1% develop a fever and/or muscle aches.^[4]

Vaccination schedule

Adults

The 23-valent vaccine (e.g., PNEUMOVAX 23) is effective against 23 different pneumococcal sub-forms (serotypes). It is only appropriate for adults and usually should only be administered once if you are over the age of 65. If you are under the age of 65 when you received your vaccination, a booster will be needed every 5 years until you reached the age of 65.^{[citation needed]} In special circumstances, in people with high risk of acquiring pneumococcal pneumonia (asplenia, immunosuppressed, etc) more frequent revaccination (less than once per 5 year) might be needed.^{[citation needed]}

Children

Children under the age of two years fail to mount an adequate response to the 23-valent adult vaccine, and instead a 7-valent Pneumococcal Conjugated Vaccine (PCV) (e.g. Prevnar) must be used. Whilst this covers only seven strains out of more than ninety strains, these seven strains cause 80% to 90% of cases of severe pneumococcal disease, and it is considered to be nearly 100% effective against these strains.^[5]

Special risk-group

Children at special risk (e.g. sickle cell disease and asplenia) require as full protection as can be achieved using the 7-valent congugated vaccine, with the then more extensive 23-valent vaccine given after the second year of life:

See also

• Streptococcus pneumoniae
• Pneumonia

Notes and references

1. ^ Pneumococcal Conjugate Vaccine: What a Parent Needs to Know - information from the American Academy of Family Physicians website - FamilyDoctor.org. Gives statistics of pneumococcal disease incidence and the occurrence rates of various side effects.
2. ^ US Centers for Disease Control and Prevention. Pneumococcal diseae in short. http://www.cdc.gov/vaccines/vpd-vac/pneumo/in-short-both.htm.
3. ^ World Health Organization. Pneumococcal vaccines. http://www.who.int/vaccines/en/pneumococcus.shtml#position.
4. ^ US Centers for Disease Control and Prevention. Pneumococcal Polysaccharide Vaccine: What You Need to Know. 2009. http://www.cdc.gov/vaccines/pubs/vis/downloads/vis-ppv.pdf.
5. ^ Childhood Pneumococcal Disease - information on the disease and the Prevnar vaccine, from the Victoria State (Australia) government. Includes possible side effects.
6. ^ "Chapter 25: Pneumococcal" (PDF). Immunisation against infectious disease - 'The Green Book'. Department of Heath (UK). 2006. http://www.dh.gov.uk/dr_consum_dh/groups/dh_digitalassets/@dh/@en/documents/digitalasset/dh_063655.pdf. 

External links

• World Health Organization: Pneumococcal Vaccines.
• Merck PNEUMOVAX 23 information
• PATH's Vaccine Resource Library pneumococcus resources