Pneumonia History. News Medical Lifesciences Oct 11, Thorax ; 53 3 Geographical differences in invasive pneumococcal disease rates and serotype frequency in young children. March 24, : Clin Microbiol Rev. PloS Genetics May 1, Am J Public Health. Lancet May 28; : News Medical Oct 11, Yale J Biol Med. N Engl J Med. Pneumococcal Disease: Drug Resistance. Page N Engl J Med April 6, ; Jan 30, Global priority list of antibiotic-resistant bacteria to guide research, discovery, and development of new antibiotics Reported cases of notifiable diseases, by region and reporting area - - United States and U.
Initially, vaccines of killed pneumococcal cells prepared in a variety of ways were used in epidemic settings with inconclusive results, although administered to approximately 1 million recipients. The discovery that adults injected with small amounts of purified capsular polysaccharide developed antibodies to the homologous capsular type led to the trial of a tetravalent vaccine that showed conclusively its ability to prevent infection by the types represented in it.
The first pneumococcal vaccine was licensed for use in the United States in The first conjugate pneumococcal vaccine was licensed in the United States in They are typically observed in pairs diplococci but may also occur singularly or in short chains.
Most pneumococci are encapsulated, and their surfaces are composed of complex polysaccharides. Capsular polysaccharides are one determinant of the pathogenicity of the organism. They are also antigenic and form the basis for classifying pneumococci by serotypes. One hundred serotypes were documented as of , based on their reaction with type-specific antisera.
Type-specific antibody to capsular polysaccharide is protective against disease caused by that serotype. These antibodies and complement interact to opsonize pneumococci, which facilitates phagocytosis and clearance of the organism. Antibodies to some pneumococcal capsular polysaccharides may cross-react with related types as well as with other bacteria, providing protection against additional serotypes.
Most S. The ranking and serotype prevalence differ by patient age group and geographic area. The clinical spectrum of pneumococcal infections ranges from invasive disease i.
Over , hospitalizations from pneumococcal pneumonia are estimated to occur annually in the United States and it has been demonstrated to complicate influenza infection. Pneumococci is the most common bacterial cause of childhood pneumonia, especially in children younger than age 5 years. Rates of asymptomatic carriage vary with age, environment, and the presence of upper respiratory infections. The duration of carriage varies and is generally longer in children than adults.
The relationship of carriage to the development of natural immunity is poorly understood. The major clinical syndromes of invasive pneumococcal disease are pneumonia, bacteremia, and meningitis.
Pneumococcal pneumonia is the most common clinical presentation of pneumococcal disease among adults. The incubation period of pneumococcal pneumonia is short, about 1 to 3 days. Symptoms generally include an abrupt onset of fever and chills or a single rigor. Repeated shaking chills are uncommon. Other common symptoms include pleuritic chest pain, cough productive of mucopurulent, rusty sputum, dyspnea, tachypnea, hypoxia, tachycardia, malaise, and weakness.
Nausea, vomiting, and headaches occur less frequently. Complications of pneumococcal pneumonia include bacteremia, empyema i. Pneumococcal bacteremia can occur with or without pneumonia and lead to arthritis, meningitis, and endocarditis. More than 5, cases of pneumococcal bacteremia without pneumonia occur each year. Patients with asplenia who develop bacteremia may experience a fulminant clinical course.
Some patients with pneumococcal meningitis also have pneumonia. The clinical symptoms, CSF profile, and neurologic complications of pneumococcal meningitis are similar to other forms of purulent bacterial meningitis. Symptoms may include headache, lethargy, vomiting, irritability, fever, nuchal rigidity, cranial nerve signs, seizures, and coma. Neurologic sequelae are common among survivors. Adults with certain medical conditions are at highest risk for invasive pneumococcal disease.
For adults age 18 through 64 years with hematologic cancer, the rate of invasive pneumococcal disease in — was per , population. Other conditions that place adults at highest risk for invasive pneumococcal disease include other immunosuppressive conditions from disease or drugs, functional or anatomic asplenia, and renal disease. Other conditions that increase the risk of invasive pneumococcal disease in adults include chronic heart disease, lung disease including asthma , liver disease, smoking cigarettes, alcoholism, CSF leak, and having a cochlear implant.
With the decline of invasive Haemophilus influenzae type b Hib disease, S. Before routine use of pneumococcal conjugate vaccine, children younger than 1 year had the highest rates of pneumococcal meningitis, approximately 10 cases per , population.
Middle ear infections are a leading reason for pediatric office visits in the United States, resulting in more than 10 million visits annually. Complications of pneumococcal otitis media may include mastoiditis and meningitis. Children with functional or anatomic asplenia, particularly those with sickle cell disease, and children with immunocompromising conditions are at very high risk for invasive disease, with rates in some studies more than 50 times higher than those among children of the same age without these conditions i.
Other conditions that increase the risk of invasive pneumococcal disease in children include chronic heart disease, lung disease including asthma if treated with high-dose oral corticosteroid therapy , liver disease, CSF leak, and having a cochlear implant. Rates are also increased among children of certain racial and ethnic groups, including Alaska Natives, African Americans, and certain American Indian groups Navajo and White Mountain Apache.
The reason for this increased risk by race and ethnicity is not known with certainty but has also been noted for invasive Haemophilus influenzae infection also an encapsulated bacterium. Attendance at a childcare center has also been shown to increase the risk of invasive pneumococcal disease and acute otitis media 2- or 3-fold among children younger than age 5 years.
Children with a cochlear implant are at increased risk for pneumococcal meningitis. A definitive diagnosis of infection with S. Tests are also available to detect capsular polysaccharide antigen in body fluids.
The appearance of lancet-shaped diplococci on Gram stain is suggestive of pneumococcal infection, but interpretation of stained sputum specimens may be difficult because of the presence of normal nasopharyngeal bacteria.
The suggested criteria for obtaining a diagnosis of pneumococcal pneumonia using gram-stained sputum includes more than 25 white blood cells and fewer than 10 epithelial cells per low-power field, and a predominance of gram-positive diplococci. A urinary antigen test based on an immunochromatographic membrane technique to detect the C-polysaccharide antigen of S.
The test is rapid and simple to use, has a reasonable specificity in adults, and has the ability to detect pneumococcal pneumonia after antibiotic therapy has been started. Following introduction of PCV7, antibiotic resistance declined and then began to increase again. Then, in , the definition of penicillin resistance was changed such that a much larger proportion of pneumococci were considered susceptible to penicillin.
The revised susceptibility breakpoints for S. Since introduction of valent pneumococcal conjugate vaccine PCV13 in children in , antibiotic-resistant pneumococcal infections declined significantly. Pneumococcal vaccination: What everyone should know. Morbidity and Mortality Weekly Report. Muller, M. Pediatric bacterial meningitis.
Merck licensed a polysaccharide vaccine protecting against 14 types of pneumococcal bacteria in In , Merck expanded on this work by producing a vaccine against 23 types of pneumococcal bacteria. One challenge in producing a pneumococcal vaccine involved determining which of the more than 90 types of pneumococcal bacteria produced the most disease. Once that work was complete, Robert Austrian, MD, at the University of Pennsylvania isolated the types most appropriate for the vaccine and provided this information to Hilleman at Merck.
Merck researchers then developed the vaccine from the polysaccharide outer coatings of the bacteria. True or false? Many people have Streptococcus pneumoniae in their noses and throats without becoming ill. Article Menu [ ]. Vaccine Science [ ]. Biological Weapons, Bioterrorism, and Vaccines. Cancer Vaccines and Immunotherapy. Careers in Vaccine Research. Ebola Virus Disease and Ebola Vaccines. Human Cell Strains in Vaccine Development.
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