Fried egg appearance is found in mycoplasma colonies.
Mycoplasma colonies:

biphasic – distinct central and peripheral zones
central zone – opaque, granular – growth extending into the depth of the medium
peripheral zone – translucent, flat

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Mycoplasma

When a blood film containing anthrax bacilli is stained using polychrome methylene blue for a few seconds and observed under microscope, a purplish coat of amorphous material is seen around a blue stained bacilli. The amorphous purple material is the capsule. This is called Mc Fadyean’s reaction and is used in the presumptive diagnosis of anthrax in animals.

Rickettsial disease are of 2 types – typhus group and spotted fever group.
Typhus group:

Epidemic typhus / Classic typhus / louse borne typhus / gaol fever – Rickettsia prowazekii
Edemic typhus / murine typhus / fleaborne typhus – Rickettsia typhi

Spotter fever group:

Rocky mountain spotted fever – Rickettsia rickettsii
Oriental spotted fever – Rickettsia japonica
Rickettsial pox – Rickettsia akari

Haemophilus influenzae produces both invasive and non invasive infections
Invasive diseases are usually caused by capsulated strains. The bacilli are protected from phagocytes by the capsule and spread through blood. The various invasive infections are:

Meningitis – most common
conjunctivitis
laryngoepiglottitis
pneumonia
pericarditis
endocarditis
arthritis
bacteremia

Non invasive diseases usually occur as superadded infections and are often caused by non capsulated strains. It spreads locally in the mucous membranes and are associated with respiratory infections. The various conditions include:

otitis media
sinusitis
acute exacerbation of chronic bronchitis, bronchiectasis

Presence of bacteria in the blood

Smith, Andrewes and Laidlaw in 1933.

Wayson stain of Yersinia pestis showing characteristic safety pin appearance
Wayson stain is a modified methylene blue stain used to demonstrate Yersinia pestis for diagnosis of bubonic plague.

Acute emphysematous cholecystitis
Post cholecystectomy septicemia

Gas gangrene
food poisoning
necrotising enteritis
gangrenous appendicitis
brain abscess and meningitis
panophthalmitis
thoracic infections
endogenous gas gangrene of intraabdominal origin
biliary tract infections
urogenital infections