Streptococcus pneumoniae is one of the leading bacterial causes of meningitis, usually affecting young children and the elderly. This bacterium is an encapsulate polysaccharide, meaning that is has an outer covering consisting of a polysaccharide compound. This polysaccharide capsule acts as a virulence factor for the organism. The diversity of capsular species is large, with over 93 serotypes of this virus. This gram-positive (purple under the microscope), alpha hemolytic (having a dark agar), lancet-shaped (oval) bacteria is also known to cause bronchitis and conjunctivitis.
Virulence Factors: molecules produced by pathogens ) that contribute to the pathogenicity of the organism and enable them to achieve the following:
Serotype:
a distinct variation within species of bacteria that allow them to be classified differently. For this reason, there are "sub-groups" of bacteria, despite their cell surface antigens being similar.
Each serotype of Streptococcus pneumoniae is responsible for outbreaks all across the globe. Being so many, no one serotype is prominent. However, serotypes 1 and 5 are most common in developing countries.
Gram-Positive:
Bacteria that give a positive result in the Gram stain test. Gram-positive bacteria take up the crystal violet stain used in the test, and then appear purple in color when seen through a microscope.
Gram-Stain Test:
Gram staining differentiates bacteria by the chemical and physical properties of their cell walls by detecting peptidoglycan, which is present in a thick layer in Gram-positive bacteria. By preparing cultures of bacteria in petri dishes and adding the indicator of the Gram-Stain test, along with additional amounts of iodine solution, the bacteria will retain a specific color, indicating if it is gram-positive or gram-negative.
Meningitis due to S. pneumoniae occurs most commonly in the very young and the very old, with an estimated incidence rate of 17 cases per 100,000 population in children less than five years of age. The case fatality rate for meningitis due to S. pneumoniae in children less than five years of age exceeds 73% in some parts of the world.
The pneumococchal polysaccharide vaccine (PPSV13 and PPSV7) were released in 2010. These vaccines are generally given as booster shots to newborns. PPSV works by exposing you to a small dose of the bacteria or a protein from the bacteria, which causes your body to develop immunity to the disease.
I'm interested in researching more about the gram-stain test and obtaining different types of bacteria in order to use this test in a laboratory setting.
Virulence Factors: molecules produced by pathogens ) that contribute to the pathogenicity of the organism and enable them to achieve the following:
- colonization of a niche in the host (this includes attachment to cells)
- immunoevasion, evasion of the host's immune response
- immunosuppression, inhibition of the host's immune response
- entry into and exit out of cells (if the pathogen is an intracellular one)
- obtain nutrition from the host
Serotype:
a distinct variation within species of bacteria that allow them to be classified differently. For this reason, there are "sub-groups" of bacteria, despite their cell surface antigens being similar.
Each serotype of Streptococcus pneumoniae is responsible for outbreaks all across the globe. Being so many, no one serotype is prominent. However, serotypes 1 and 5 are most common in developing countries.
Gram-Positive:
Bacteria that give a positive result in the Gram stain test. Gram-positive bacteria take up the crystal violet stain used in the test, and then appear purple in color when seen through a microscope.
Gram-Stain Test:
Gram staining differentiates bacteria by the chemical and physical properties of their cell walls by detecting peptidoglycan, which is present in a thick layer in Gram-positive bacteria. By preparing cultures of bacteria in petri dishes and adding the indicator of the Gram-Stain test, along with additional amounts of iodine solution, the bacteria will retain a specific color, indicating if it is gram-positive or gram-negative.
Meningitis due to S. pneumoniae occurs most commonly in the very young and the very old, with an estimated incidence rate of 17 cases per 100,000 population in children less than five years of age. The case fatality rate for meningitis due to S. pneumoniae in children less than five years of age exceeds 73% in some parts of the world.
The pneumococchal polysaccharide vaccine (PPSV13 and PPSV7) were released in 2010. These vaccines are generally given as booster shots to newborns. PPSV works by exposing you to a small dose of the bacteria or a protein from the bacteria, which causes your body to develop immunity to the disease.
I'm interested in researching more about the gram-stain test and obtaining different types of bacteria in order to use this test in a laboratory setting.