Q fever pathophysiology: Difference between revisions
Ahmed Younes (talk | contribs) No edit summary |
Ahmed Younes (talk | contribs) |
||
| Line 36: | Line 36: | ||
Phase II: characterized by rough lipopolysacharide capsule and antibodies against phase II have been isolated from chronic Q fever patients. | Phase II: characterized by rough lipopolysacharide capsule and antibodies against phase II have been isolated from chronic Q fever patients. | ||
Q fever as a biological weapon: | ===Q fever as a biological weapon:=== | ||
C. Brutenii is an extremely virulent organism. | C. Brutenii is an extremely virulent organism. | ||
| Line 45: | Line 45: | ||
*Causing chronic illness in 9,000 individuals | *Causing chronic illness in 9,000 individuals | ||
Microscopic pathology: | ===Microscopic pathology:=== | ||
*C. Brutenii is a gram negative polymorphic intracellular organism. | *C. Brutenii is a gram negative polymorphic intracellular organism. | ||
*It was previously classified as a ricketsia, but now is considered a proteobacterium. | *It was previously classified as a ricketsia, but now is considered a proteobacterium. | ||
==References== | ==References== | ||
Revision as of 15:55, 6 June 2017
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
|
Q fever Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Case Studies |
|
Q fever pathophysiology On the Web |
|
American Roentgen Ray Society Images of Q fever pathophysiology |
|
Risk calculators and risk factors for Q fever pathophysiology |
Overview
Pathophysiology
Transmission:
The organism is transmitted through:
- Aerosoloes: Inhalation of contaminated aerosoles is the main mode of transmission.
- Ingestion of raw dairy products
- Vertical (mother to fetus) transmission has been reported
- Parentral
- (Through tick bites
Pathogenesis:
C. Brutenii has the ability to exist in 2 forms:
Small cell form: Often described as the spore form of C. Brutenii Resists the external environmental factors as heat, pressure and dissinfectants for long periods
Large cell form: The active form of the organism Large cell form persists in the macrophages inside acidic vacuoles.
Small and large cell forms are antigenically different and this plays a role in the virulence of the organism. The genome of C. Brutenii has been analysed in 1995. Multiple genes encoding for Na/ ion proton exchanger have been discovered and this explains the ability of the organism to survive in low PH.
The infection has 2 phases that correlate with changes in the lipopolysaccharide of C. Brutenii.
Phase I: characterized by smooth lipopolysacharide capsule. Despite being less efficient in invasion of host cells, antibodies against phase I is always isolated from acute Q fever patients.
Phase II: characterized by rough lipopolysacharide capsule and antibodies against phase II have been isolated from chronic Q fever patients.
Q fever as a biological weapon:
C. Brutenii is an extremely virulent organism. According to WHO estimates, an amount of 50 kg of C. Brutenii if spread in an area of 2 square kilometers is capable of:
- Infecting 500,000 humans
- Killing 150 individuals
- Causing acute illness in 125,000 individuals
- Causing chronic illness in 9,000 individuals
Microscopic pathology:
- C. Brutenii is a gram negative polymorphic intracellular organism.
- It was previously classified as a ricketsia, but now is considered a proteobacterium.