The most common causes of bacterial meningitis can be the result of infection by three very different bacteria. which bacteria are they and how are these microbes similar to each other?

3 different bacteria which cause bacterial meningitis are Streptococcus pneumoniae, Neisseria Meningitidis and Haemophilus influenzae

Explanation:

N. meningitidis is a gram-negative β proteobacterium and member of the bacterial family of Neisseriaceae. N. meningitidis is a fastidious bacterium, dying within hours on inanimate surfaces, and is either an encapsulated or unencapsulated, aerobic diplococcus with a “kidney” or “coffee-bean” shape.

Streptococcus pneumoniae are Gram-positive bacteria in the shape of a slightly pointed cocci. They are usually found in pairs (diplococci), but are also found singly and in short chains.

Haemophilus influenzae is a small (1 µm × 0.3 µm), pleomorphic, gram-negative coccobacillus. Some strains of H influenzae possess a polysaccharide capsule, and these strains are serotyped into 6 different types (a-f) based on their biochemically different capsules. The most virulent strain is H influenzae type b (Hib). Some H influenzae strains have no capsule and are termed nonencapsulated H influenzae or nontypeable H influenzae (NTHi).

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