Pneumococcal vaccine
Encyclopedia
A pneumococcal vaccine is a vaccine
against Streptococcus pneumoniae
.
Types include:
vaccine (PCV 7) (e.g. Prevenar) was recommended for all children aged 2–23 months and for at-risk children aged 24–59 months in 2000. The normal 4-dose series is given at 2, 4, 6 & 12–14 months of age. In February 2010, a pneumococcal congugate vaccine which protects against an additional 6 serotypes was introduced (PCV 13 / brand name: Prevnar 13) and can be given instead of the original Prevnar. Similar 9-, and 10-valent vaccines have been tested. Protection is good against deep pneumococcal infections (especially septicemia and meningitis). However, if a child is exposed to a serotype of pneumococcus that is not contained in the vaccine, he/she is not afforded any protection. This limitation, and the ability of capsular-polysaccharide conjugate vaccines to promote the spread of non-covered serotypes, has led to research into vaccines that would provide species-wide protection.
Pneumococcal polysaccharide vaccine
(Pneumovax is one brand) gives at least 85% protection in those under 55 years of age for five years or longer. Immunization is suggested for those at highest risk of infection, including those 65 years or older; generally the vaccine should be a single lifetime dose, as there is a high risk of side effects if repeated. The standard 23-valent vaccines are ineffective for children under two years old.
The current guidelines of the American College of Physicians
call for administration of the immunization between ages 2 and 65 when indicated, or at age 65. If someone received the immunization before age 60, the guidelines call for a one-time revaccination.
Revaccination at periodic intervals is also indicated for those with other conditions such as asplenia
or nephrotic syndrome
.
is a program to accelerate the evaluation and access to new pneumococcal vaccines in the developing world. PneumoADIP is funded by the Global Alliance for Vaccines and Immunization (GAVI)
. Thirty GAVI countries have expressed interest in participating by 2010. PneumoADIP aims to save 5.4 million children by 2030.
There is currently research into producing vaccines than can be given into the nose rather than by injection.
It is believed that this improves vaccine efficacy and also avoids the need for injection.
The development of serotype-specific anticapsular monoclonal antibodies has also been researched in recent years. These antibodies have been shown to prolong survival in a mouse model of pneumococcal infection characterized by a reduction in bacterial loads and a suppression of the host inflammatory response. Additional pneumococcal vaccine research is taking place to find a vaccine that offers broad protection against pneumococcal disease.
Vaccine
A vaccine is a biological preparation that improves immunity to a particular disease. A vaccine typically contains an agent that resembles a disease-causing microorganism, and is often made from weakened or killed forms of the microbe or its toxins...
against Streptococcus pneumoniae
Streptococcus pneumoniae
Streptococcus pneumoniae, or pneumococcus, is Gram-positive, alpha-hemolytic, aerotolerant anaerobic member of the genus Streptococcus. A significant human pathogenic bacterium, S...
.
Types include:
- Pneumococcal polysaccharide vaccinePneumococcal polysaccharide vaccinePneumococcal polysaccharide vaccine — the latest version is known as Pneumovax 23 — is the first pneumococcal vaccine, the first vaccine derived from a capsular polysaccharide, and an important landmark in medical history...
- Pneumococcal conjugate vaccine
Vaccination in the USA
In the USA, a heptavalent pneumococcal conjugate vaccineConjugate vaccine
A conjugate vaccine is created by covalently attaching a poor antigen to a carrier protein , thereby conferring the immunological attributes of the carrier on the attached antigen...
vaccine (PCV 7) (e.g. Prevenar) was recommended for all children aged 2–23 months and for at-risk children aged 24–59 months in 2000. The normal 4-dose series is given at 2, 4, 6 & 12–14 months of age. In February 2010, a pneumococcal congugate vaccine which protects against an additional 6 serotypes was introduced (PCV 13 / brand name: Prevnar 13) and can be given instead of the original Prevnar. Similar 9-, and 10-valent vaccines have been tested. Protection is good against deep pneumococcal infections (especially septicemia and meningitis). However, if a child is exposed to a serotype of pneumococcus that is not contained in the vaccine, he/she is not afforded any protection. This limitation, and the ability of capsular-polysaccharide conjugate vaccines to promote the spread of non-covered serotypes, has led to research into vaccines that would provide species-wide protection.
Pneumococcal polysaccharide vaccine
Pneumococcal polysaccharide vaccine
Pneumococcal polysaccharide vaccine — the latest version is known as Pneumovax 23 — is the first pneumococcal vaccine, the first vaccine derived from a capsular polysaccharide, and an important landmark in medical history...
(Pneumovax is one brand) gives at least 85% protection in those under 55 years of age for five years or longer. Immunization is suggested for those at highest risk of infection, including those 65 years or older; generally the vaccine should be a single lifetime dose, as there is a high risk of side effects if repeated. The standard 23-valent vaccines are ineffective for children under two years old.
The current guidelines of the American College of Physicians
American College of Physicians
The American College of Physicians is a national organization of doctors of internal medicine —physicians who specialize in the prevention, detection, and treatment of illnesses in adults. With 130,000 members, ACP is the largest medical-specialty organization and second-largest physician group in...
call for administration of the immunization between ages 2 and 65 when indicated, or at age 65. If someone received the immunization before age 60, the guidelines call for a one-time revaccination.
Revaccination at periodic intervals is also indicated for those with other conditions such as asplenia
Asplenia
Asplenia refers to the absence of normal spleen function and is associated with some serious infection risks. Hyposplenism is used to describe reduced splenic functioning, but not as severely affected as with asplenism.-Congenital:...
or nephrotic syndrome
Nephrotic syndrome
Nephrotic syndrome is a nonspecific disorder in which the kidneys are damaged, causing them to leak large amounts of protein from the blood into the urine....
.
Vaccination in the UK
It was announced in February 2006 that the UK government would introduce vaccination with the conjugate vaccine in children aged 2, 4 and 13 months. This is expected to start on September 4, 2006 and is to include changes to the immunisation programme in general. In 2009, the European Medicines Agency approved the use of a 10-valent pneumcoccal conjugate vaccine for use in Europe.. The 13 valent pneumococcal vaccine has been introduced in the routine immunisation schedule of the UK in April 2010.Vaccination in South Africa
Pneumovax 23 is used, and according to the enclosed patient information leaflet, has a reported 76% to 92% protective efficacy (pneumococcal types 1, 2, 3, 4, 5, 6B**, 7F, 8, 9N, 9V**, 10A, 11A, 12F, 14**, 15B, 17F, 18C, 19A**, 19F**, 20, 22F, 23F** and 33F** are included, where ** indicates drug resistant pneumococcal infections; these are the 23 most prevalent or invasive pneumococcal types of Streptococcus pneumoniae).Vaccination worldwide
Pneumococcal vaccines Accelerated Development and Introduction Plan (PnemoADIP)PneumoADIP
Pneumococcal vaccines Accelerated Development and Introduction Plan is a small, dedicated team based at Johns Hopkins Bloomberg School of Public Health and is supported by a $30 million grant from the Global Alliance for Vaccines and Immunization...
is a program to accelerate the evaluation and access to new pneumococcal vaccines in the developing world. PneumoADIP is funded by the Global Alliance for Vaccines and Immunization (GAVI)
Global Alliance for Vaccines and Immunization
The GAVI Alliance is a public-private global health partnership committed to saving children’s lives and protecting people’s health by increasing access to immunisation in poor countries...
. Thirty GAVI countries have expressed interest in participating by 2010. PneumoADIP aims to save 5.4 million children by 2030.
Vaccine research
Due to the geographic distribution of pneumococcal serotypes, additional research is needed to find the most efficacious vaccine for developing-world populations. In a previous study, the most common pneumococcal serotypes or groups from developed countries were found to be, in descending order, 14, 6, 19, 18, 9, 23, 7, 4, 1 and 15. In developing countries the order was 6, 14, 8, 5, 1, 19, 9, 23, 18, 15 and 7. In order to further pneumococcal vaccine research and reduce childhood mortality, five countries and the Bill & Melinda Gates Foundation established a pilot Advance Market Commitment for pneumococal vaccines worth US$1.5 billion. Advance Market Commitments are a new approach to public health funding designed to stimulate the development and manufacture of vaccines for developing countries.There is currently research into producing vaccines than can be given into the nose rather than by injection.
It is believed that this improves vaccine efficacy and also avoids the need for injection.
The development of serotype-specific anticapsular monoclonal antibodies has also been researched in recent years. These antibodies have been shown to prolong survival in a mouse model of pneumococcal infection characterized by a reduction in bacterial loads and a suppression of the host inflammatory response. Additional pneumococcal vaccine research is taking place to find a vaccine that offers broad protection against pneumococcal disease.