Pneumococcal vaccines are vaccines against the bacterium Streptococcus pneumoniae .Their use can prevent some cases of pneumonia, meningitis, and sepsis. There are two types of pneumococcal vaccines: conjugate vaccines and polysaccharide vaccines. They are given by injection either into a muscle or just under the skin.
The World Health Organization (WHO) recommends the use of the conjugate vaccine in the routine immunizations given to children.This includes those with HIV/AIDS. The recommended three or four doses are between 71 and 93% effective at preventing severe pneumococcal disease. The polysaccharide vaccines, while effective in healthy adults, are not effective in children less than two years old or those with poor immune function.
These vaccines are generally safe.With the conjugate vaccine about 10% of babies develop redness at the site of injection, fever, or change in sleep. Severe allergies are very rare.
The first pneumococcal vaccine was developed in the 1980s.It is on the World Health Organization's List of Essential Medicines.
Pneumococcal vaccines Accelerated Development and Introduction Plan (PneumoADIP) 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.
A pilot Advance Market Commitment (AMC) to develop a vaccine against pneumococcus was launched by GAVI in June 2009 as a strategy to address two of the major policy challenges to vaccine introduction: a lack of affordable vaccines on the market, and insufficient commercial incentives to develop vaccines for diseases concentrated in developing countries. Under the terms of an AMC, donors make a legally binding guarantee that, if a future vaccine is developed against a particular disease, they will purchase a predetermined amount at an agreed-upon price. The guarantee is linked to safety and efficacy standards that the vaccine must meet and is structured in a way to allow several firms to compete to develop and produce the best possible new product. AMCs reduce risk to donor governments by eliminating the need to fund individual research and development projects that may never produce a vaccine. If no company produces a vaccine that meets the predetermined standards, governments (and thus their taxpayers) spend nothing. For the bio-pharmaceutical industry, AMCs create a guaranteed market, with a promise of returns that would not normally exist. For developing countries, AMCs provide funding to ensure that those vaccines will be affordable once they have been developed. It is estimated that the pneumococcal AMC could prevent more than 1.5 million childhood deaths by 2020. [ third-party source needed ]
Doctors without borders has criticized GAVI's pneumococcal AMC for not encouraging innovation, discouraging competition from new market entrants, and raising vaccine costs. They said that it had allowed Pfizer and GlaxoSmithKline to maintain a duopoly, while making it more difficult for the Serum Institute of India to sell their cheaper vaccine. The duopoly allowed price discrimination; somewhat higher prices for GAVI, and unaffordable prices (about ten time the GAVI price) for middle-income countries too rich for GAVI aid. [ third-party source needed ]) did not include any mechanism for increasing competition.The pneumococcal program (unlike previous market-shaping programs from GAVI
The Humanitarian Mechanism makes the pneumococcal vaccine available to humanitarian actors (but not governments) at a lower than normal price during humanitarian emergencies.
In May 2017, the Government of India decided to include pneumococcal conjugate vaccine in its Universal Immunization Programme.
In the United States, a heptavalent pneumococcal conjugate vaccine (PCV 7) (e.g. Prevnar, called Prevenar in some countries) was recommended for all children aged 2–23 months and for at-risk children aged 24–59 months in 2000. The normal four-dose series is given at 2, 4, 6 and 12–14 months of age. In February 2010, a pneumococcal conjugate vaccine which protects against an additional six serotypes was introduced (PCV 13/brand name: Prevnar 13) and can be given instead of the original Prevnar.
Pneumococcal polysaccharide vaccine (PPV, Pneumovax is one brand) gives at least 85% protection in those under 55 years of age for five years or longer.[ medical citation needed ] 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.[ medical citation needed ] The standard 23-valent vaccines are ineffective for children under two years old.[ medical citation needed ]
The current[ when? ] guidelines of the American College of Physicians call for the administration of the immunization between ages two and 65 when indicated, or at age 65. If someone received the immunization before age 60, the guidelines call for one-time revaccination.[ medical citation needed ] A majority of pharmacists indicate that they recommend all adults 65 and older receive a pneumococcal vaccination. They are generally educated on ACIP/CDC recommendations and believe that all people, regardless of age, should also be caught up on them.
Revaccination at periodic intervals is also indicated for those with other conditions such as asplenia or nephrotic syndrome.[ medical citation needed ]
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. [ citation needed ]This included changes to the immunisation programme in general. In 2009, the European Medicines Agency approved the use of a 10 valent pneumococcal conjugate vaccine for use in Europe. The 13 valent pneumococcal vaccine was introduced in the routine immunization schedule of the UK in April 2010.
The 7- and 13-valent pneumococcal conjugate vaccines (PCV7 and PCV13) were introduced into the national Expanded Program on Immunization (EPI) in South Africa in 2009 and 2011, respectively. South Africa became the first African country – and the first nation in the world with a high HIV prevalence – to introduce PCV7 into its routine immunization program. [ medical citation needed ]Rates of invasive pneumococcal disease – including cases caused by antibiotic-resistant bacteria – have fallen substantially in South Africa following the introduction of PCV7. Among children under two years of age, the overall incidence of IPD declined nearly 70% after PCV introduction, and rates of IPD caused by bacteria specifically targeted by the vaccine decreased nearly 90%. Due to the indirect protection conferred by herd immunity, a significant decline in IPD in children and in unvaccinated adults has also been shown. Pneumovax 23 is used for all ages 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).
Health Canada's general recommendations are 13-valent pneumococcal conjugate vaccine (PCV 13) vaccine for children aged 2 months to 18 years and 23-valent pneumococcal polysaccharide vaccine (PPV 23) vaccine for adults.
Local reactions such as pain, swelling, or redness occur in up to 50% of those vaccinated with PCV13; of these, 8% are considered severe. Local reactions are more likely after the 4th dose than the earlier doses.In clinical trials, fever greater than 100.4 F (38 C) was reported at a rate of 24-35% following any dose in the primary series and nonspecific symptoms such as decreased appetite or irritability occur in up to 80% of recipients. In a vaccine safety datalink study, febrile seizures occurred in roughly 1 in 83,000 to 1 in 6,000 children given PCV 13, and 1 in 21,000 to 1 in 2,000 of those who were given PCV13 and trivalent influenza vaccine at the same time.
The pneumococcal polysaccharide vaccine most commonly used today [ citation needed ] consists of purified polysaccharides from 23 serotypes (1, 2, 3, 4, 5, 6b, 7F, 8, 9N, 9V, 10A, 11A, 12F, 14, 15B, 17F, 18C, 19A, 19F, 20, 22F, 23F, and 33F). Immunity is induced primarily through stimulation of B-cells which release IgM without the assistance of T cells.
This immune response is less robust than the response provoked by conjugated vaccines, which has several consequences. The vaccine is ineffective in children less than 2 years old, presumably due to their less mature immune systems.Non-response is also common amongst older adults. Immunity is not lifelong, so individuals must be re-vaccinated at age 65 if their initial vaccination was given at age 60 or younger. Since no mucosal immunity is provoked, the vaccine does not affect carrier rates, promote herd immunity, or protect against upper or lower respiratory tract infections. Finally, provoking immune responses using unconjugated polysaccharides from the capsules of other bacteria, such as H. influenzae, has proven significantly more difficult.
The pneumococcal conjugate vaccine consists of capsular polysaccharides covalently bound to the diphtheria toxoid CRM197, which is highly immunogenic but non-toxic. [ medical citation needed ]This combination provokes a significantly more robust immune response by recruiting CRM197-specific type 2 helper T cells, which allow for immunoglobulin type switching (to produce non-IgM immunoglobulin) and production of memory B cells. Among other things, this results in mucosal immunity and the eventual establishment of lifelong immunity after several exposures. The main drawbacks to conjugated vaccines are that they only provide protection against a subset of the serotypes covered by the polysaccharide vaccines.
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 pneumococcal 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[ when? ] 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.[ medical citation needed ]
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.
As of 2017 [update] , pneumonia vaccines target up to 23 forms of the bacterium that cause pneumonia with a new version under development covering 72 strains of the bacterium. [ needs update ]
Herd immunity is a form of indirect protection from infectious disease that can occur with some diseases when a sufficient percentage of a population has become immune to an infection, whether through vaccination or previous infections, thereby reducing the likelihood of infection for individuals who lack immunity. Immune individuals are unlikely to contribute to disease transmission, disrupting chains of infection, which stops or slows the spread of disease. The greater the proportion of immune individuals in a community, the smaller the probability that non-immune individuals will come into contact with an infectious individual.
Asplenia refers to the absence of normal spleen function and is associated with some serious infection risks. Hyposplenism is used to describe reduced ('hypo-') splenic functioning, but not as severely affected as with asplenism.
A conjugate vaccine is a type of vaccine which combines a weak antigen with a strong antigen as a carrier so that the immune system has a stronger response to the weak antigen.
An advance market commitment (AMC) is a binding contract, typically offered by a government or other financial entity, used to guarantee a viable market for a product once it is successfully developed. Generally AMCs are used in circumstances where the cost of developing a new product is too high to be worthwhile for the private sector without a guarantee of a certain quantity of purchases in advance.
Pneumococcal polysaccharide vaccine (PPSV)—known as Pneumovax 23 (PPV-23)—is the first pneumococcal vaccine derived from a capsular polysaccharide, and an important landmark in medical history. The polysaccharide antigens were used to induce type-specific antibodies that enhanced opsonization, phagocytosis, and killing of Streptococcus pneumoniae (pneumococcal) bacteria by phagocytic immune cells. The pneumococcal polysaccharide vaccine is widely used in high-risk adults. As a result, there have been important reductions in the incidence, morbidity, and mortality from invasive pneumococcal disease.
A vaccination schedule is a series of vaccinations, including the timing of all doses, which may be either recommended or compulsory, depending on the country of residence. A vaccine is an antigenic preparation used to produce active immunity to a disease, in order to prevent or reduce the effects of infection by any natural or "wild" pathogen.
Artificial induction of immunity makes people immune to specific diseases by means other than waiting for them to catch the disease. The purpose is to reduce the risk of death and suffering.
Pneumococcal conjugate vaccine (PCV) is a pneumococcal vaccine and a conjugate vaccine used to protect infants, young children, and adults against disease caused by the bacterium Streptococcus pneumoniae (pneumococcus). It contains purified capsular polysaccharide of pneumococcal serotypes conjugated to a carrier protein to improve antibody response compared to the pneumococcal polysaccharide vaccine. The World Health Organization (WHO) recommends the use of the conjugate vaccine in routine immunizations given to children. There are three types of PCV available, with the brand names Prevnar 13, Synflorix, and Pneumosil, which was prequalified by the WHO in 2020.
The Haemophilus influenzae type B vaccine, often called Hib vaccine, is a vaccine used to prevent Haemophilus influenzae type b (Hib) infection. In countries that include it as a routine vaccine, rates of severe Hib infections have decreased more than 90%. It has therefore resulted in a decrease in the rate of meningitis, pneumonia, and epiglottitis.
A pneumococcal infection is an infection caused by the bacterium Streptococcus pneumoniae, which is also called the pneumococcus. S. pneumoniae is a common member of the bacterial flora colonizing the nose and throat of 5–10% of healthy adults and 20–40% of healthy children. However, it is also a cause of significant disease, being a leading cause of pneumonia, bacterial meningitis, and sepsis. The World Health Organization estimates that in 2005 pneumococcal infections were responsible for the death of 1.6 million children worldwide.
NmVac4-A/C/Y/W-135 is the commercial name of the polysaccharide vaccine against the bacterium that causes meningococcal meningitis. The product, by JN-International Medical Corporation, is designed and formulated to be used in developing countries for protecting populations during meningitis disease epidemics.
Meningococcal vaccine refers to any of the vaccines used to prevent infection by Neisseria meningitidis. Different versions are effective against some or all of the following types of meningococcus: A, B, C, W-135, and Y. The vaccines are between 85 and 100% effective for at least two years. They result in a decrease in meningitis and sepsis among populations where they are widely used. They are given either by injection into a muscle or just under the skin.
Maria Deloria Knoll is an expert in the fields of epidemiology, disease surveillance, vaccine trial conduct, and bio-statistics. She currently serves as Associate Director of Science at the International Vaccine Access Center (IVAC), an organization dedicated to accelerating global access to life-saving vaccines, at the Johns Hopkins Bloomberg School of Public Health in Baltimore, Maryland.
Orin Levine is an epidemiologist known for his work in the fields of international public health, child survival, and pneumonia. He is currently the Director of Vaccine Delivery at the Bill & Melinda Gates Foundation in Seattle, USA. In the past he was the Executive Director of the International Vaccine Access Center (IVAC), the Co-Chair of the Pneumococcal Awareness Council of Experts (PACE), and is a Professor at The Johns Hopkins Bloomberg School of Public Health in the Department of International Health. He is also an adjunct assistant professor of Epidemiology at The Rollins School of Public Health at Emory University in Atlanta. Additionally, he is currently president of the American Society of Tropical Medicine and Hygiene (ASTMH) Council on Global Health. He resides in Washington, DC.
The Global Coalition Against Child Pneumonia exists to raise global awareness about the deadly toll of the number 1 killer of children - pneumonia. Every year 155 million children under 5 get sick and 1.6 million lose their lives to pneumonia, more than all child deaths combined from AIDS, malaria and measles. Almost all of these child deaths occur in developing countries with most concentrated in just seven - India, China, Democratic Republic of Congo, Ethiopia, Nigeria, Pakistan and Afghanistan.
The Pneumococcal Awareness Council of Experts (PACE) is a project of the Sabin Vaccine Institute and is composed of global experts in infectious diseases and vaccines. Established in December 2006, The Council seeks to raise awareness among policymakers and aims to secure global commitments to prevent pneumococcal disease, a leading infectious killer of children and adults worldwide. The Council works in collaboration and partnership with countries, NGOs, academia and industry.
Universal Immunisation Programme (UIP) is a vaccination programme launched by the Government of India in 1985. It became a part of Child Survival and Safe Motherhood Programme in 1992 and is currently one of the key areas under National Rural Health Mission since 2005. The programme now consists of vaccination for 12 diseases- tuberculosis, diphtheria, pertussis, tetanus, poliomyelitis, measles, hepatitis B, diarrhoea, Japanese encephalitis, rubella, pneumonia and Pneumococcal diseases. Hepatitis B and Pneumococcal diseases was added to the UIP in 2007 and 2017 respectively. The cost of all the vaccines are borne by the state and the government spent ₹3,587 crore (US$500 million) in 2017 to purchase the vaccines to provide them for free.
GAVI, officially Gavi, the Vaccine Alliance is a public–private global health partnership with the goal of increasing access to immunisation in poor countries.
George Rainer Siber is a medical researcher and vaccine expert with 45 years of experience in developing numerous vaccines, therapeutic antibodies, and diagnostic agents for infectious diseases.
Necrotizing pneumonia (NP), also known as cavitary pneumonia or cavitatory necrosis, is a rare but severe complication of lung parenchymal infection. In necrotizing pneumonia, there is a substantial liquefaction following death of the lung tissue, which may lead to gangrene formation in the lung. In most cases patients with NP have fever, cough and bad breath, and those with more indolent infections have weight loss. Often patients clinically present with acute respiratory failure. The most common pathogens responsible for NP are Streptococcus pneumonia, Staphylococcus aureus, Klebsiella pneumoniae. Diagnosis is usually done by chest imaging, e.g. chest X-ray, CT scan. Among these CT scan is the most sensitive test which shows loss of lung architecture and multiple small thin walled cavities. Often cultures from bronchoalveolar lavage and blood may be done for identification of the causative organism(s). It is primarily managed by supportive care along with appropriate antibiotics. However, if patient develops severe complications like sepsis or fails to medical therapy, surgical resection is a reasonable option for saving life.