Difference between revisions of "Bacillus anthracis"

From QMRAwiki
Jump to: navigation, search
m (→‎References)
 
(33 intermediate revisions by 5 users not shown)
Line 1: Line 1:
−
==''Bacillus anthracis'' - Anthrax==
+
=Hosts=
−
 
 
−
===Hosts===
 
 
This bacterium infects multiple types of hosts including herbivorous mammals such as livestock and is considered zoonotic however humans are a dead end host and do not become infectious.
 
This bacterium infects multiple types of hosts including herbivorous mammals such as livestock and is considered zoonotic however humans are a dead end host and do not become infectious.
  
−
===Transmission/Exposure Routes===
+
=Transmission/Exposure Routes=
−
Cutaneous: skin contact with spores from infected animals.<br />  
+
Cutaneous: skin contact with spores from infected animals (95% of Cases; Most in Africa, Asia, and eastern Europe).<br />  
 
Gastrointestinal: eating poorly cooked meat/dairy from infected animal. <br />
 
Gastrointestinal: eating poorly cooked meat/dairy from infected animal. <br />
 
Inhalation: Inhalation of spores<br />
 
Inhalation: Inhalation of spores<br />
 +
Injectional: soft tissue infection associated with injection drug use <br/> <ref name=IntCareMed>[http://www.springerlink.com.proxy2.cl.msu.edu/content/136q4u1j54743815/fulltext.pdf Int Care Med]</ref> <br/>
 
Anthrax is not contagious and cannot be transmitted from person-to-person. <ref name=Brookmeyer></ref>
 
Anthrax is not contagious and cannot be transmitted from person-to-person. <ref name=Brookmeyer></ref>
  
−
===Case fatality ratio ===
+
=Case fatality ratio =
−
{|                                                  
+
{| class="wikitable" style="text-align:left;"                                                  
−
{| border = "1"
 
 
|+ '''Case fatality ratios'''                                   
 
|+ '''Case fatality ratios'''                                   
 
|-
 
|-
Line 34: Line 32:
 
| Not Reported
 
| Not Reported
 
| <ref name=CDC></ref>
 
| <ref name=CDC></ref>
 +
|-
 +
| 89%
 +
| Inhalation
 +
| Occupationally Acquired: 20th century untreated
 +
| <ref name=IntCareMed></ref>
 
|-
 
|-
 
| 45%
 
| 45%
Line 52: Line 55:
 
| 65% (13 of 20)
 
| 65% (13 of 20)
 
| Gastrointestinal
 
| Gastrointestinal
 +
| Children 1900-2005
 +
| <ref name=Bravata></ref>
 +
|-
 +
| 100%
 +
| Gastrointestinal
 +
| Unreported
 +
| <ref name=IntCareMed></ref>
 +
|-
 +
| 100% (6 of 6)
 +
| primary meningoencephalitis
 
| Children 1900-2005
 
| Children 1900-2005
 
| <ref name=Bravata></ref>
 
| <ref name=Bravata></ref>
Line 65: Line 78:
 
| <ref name=Kaya>Kaya A, Tasyaran M, Erol S, Ozkurt Z, and Ozkan B. (2002) Anthrax in Adults and Children: A Review of 132 Cases in Turkey. Eur J Clin Microbiol Infect Dis. 21: 258-261. [http://www.springerlink.com/content/v8ctc3ajmnwxhryn/fulltext.pdf Full Text]</ref>
 
| <ref name=Kaya>Kaya A, Tasyaran M, Erol S, Ozkurt Z, and Ozkan B. (2002) Anthrax in Adults and Children: A Review of 132 Cases in Turkey. Eur J Clin Microbiol Infect Dis. 21: 258-261. [http://www.springerlink.com/content/v8ctc3ajmnwxhryn/fulltext.pdf Full Text]</ref>
 
|-
 
|-
 +
| 30% (3 of 10)
 +
| Injectional
 +
| Adults aged 23-53, UK
 +
| <ref name=IntCareMed></ref>
 +
|-
 +
 
|}
 
|}
 
|}
 
|}
  
−
===Incubation Times===
+
=Incubation Times=
−
{|                                                  
+
{| class="wikitable" style="text-align:left;"
−
{| border = "1"
 
 
|+ '''Incubation Times'''
 
|+ '''Incubation Times'''
 
|-
 
|-
Line 102: Line 120:
 
|}
 
|}
  
−
===Burden of Disease===
+
=Burden of Disease=
  
  
 
====Duration of infectiousness and disease====
 
====Duration of infectiousness and disease====
 +
Gastrointestinal: 10-14 days<ref name=IntCareMed></ref>
 +
====Symptomology====
 +
Cutaneous: <br/>
 +
*Primary skin lesion 3-5 days after infection is painless puriritic papule.
 +
*Lesion forms a necrotic vesicle leaving a black eschar surrounded by edma.
 +
*Eschar dries and sloughs in next 1-2 weeks.
 +
<br/>
 +
Gastrointestinal: <br/>
 +
*Oral-pharyngeal form: oral or esophageal ulcer with regional lymphadenopathy edema and sepsis
 +
*Lower GI form: primary intestinal lesions predominantly in terminal ileum or cecum. Nausea, vomiting, malaise, bloody diarrhea, acute abdomen, and sepsis are common symptoms of the Lower GI form.
 +
<br/>
 +
Inhalational: <br/> Two-stages
 +
*1: Flu-like symptoms including cough fever, fatigue that last from hours to a few days
 +
*2: Rising fever, dyspnea, diaphoresis, shock. In advanced form, cyanosis and hypotension progress rapidly and death can occur within hours
 +
<br/>
 +
Injectional: <br/>
 +
*Tissue swelling around the injection site
 +
*Abdominal symptoms<ref name=IntCareMed></ref>
 +
  
−
====Symptomology====
 
−
Flu-like symptoms including:
 
−
Fever (temperature greater than 100 degrees F). The fever may be accompanied by chills or night sweats.
 
−
Cough, usually a non-productive cough, chest discomfort, shortness of breath, fatigue, muscle aches
 
−
Sore throat, followed by difficulty swallowing, enlarged lymph nodes, headache, nausea, loss of appetite, abdominal distress, vomiting, or diarrhea
 
−
   
 
 
====Excretion Rates  (see Exposure)====
 
====Excretion Rates  (see Exposure)====
 
Spores are cleared from the lung at a rate between 8-14% per day. <ref name=Brookmeyer></ref>
 
Spores are cleared from the lung at a rate between 8-14% per day. <ref name=Brookmeyer></ref>
Line 119: Line 150:
 
Anthrax vaccination consists of 5 total intramuscular injections, followed by recommended annual boosters to maintain immunity. <ref name=CDC></ref>
 
Anthrax vaccination consists of 5 total intramuscular injections, followed by recommended annual boosters to maintain immunity. <ref name=CDC></ref>
  
−
===Microbiology===
+
=Microbiology=
−
Gram +, aerobic, encapsulated, nonmotile. Exists in a dormant spore or an actively replicating vegetative rod form Extremely hardy spores can persist for years, even decades. ([http://www.springerlink.com.proxy2.cl.msu.edu/content/136q4u1j54743815/fulltext.pdf Intensive Care Med])
+
Gram +, aerobic, encapsulated, nonmotile. Exists in a dormant spore or an actively replicating vegetative rod form Extremely hardy spores can persist for years, even decades.<ref name=IntCareMed></ref>
 +
 
  
−
===Envrionmental Survival===
+
=Envrionmental Survival=
  
  
−
===Recommended Dose Response model===
+
=Recommended Dose Response model=
−
[[has DR model::Dose response models for Bacillus anthracis]]
+
[[Bacillus anthracis: Dose Response Models]]
 
<br />
 
<br />
 
Exponential model: optimal value of k is 1.65E-05 [[File:Exponential_model.png|thumb|left|200px]]
 
Exponential model: optimal value of k is 1.65E-05 [[File:Exponential_model.png|thumb|left|200px]]
Line 132: Line 164:
  
  
 +
 +
<headertabs />
  
 
===References===
 
===References===
−
 
 
<references/>
 
<references/>
−
http://en.wikipedia.org/wiki/Anthrax <br/>
+
[[Category:Bacterium]][[Category:BT category A]][[Category:Agent Overview]]
−
([http://www.springerlink.com.proxy2.cl.msu.edu/content/136q4u1j54743815/fulltext.pdf Intensive Care Med]) <br/>
 
−
[[Category:PSDS]]
 
−
[[Category:Bacterium]][[Category:BT category A]]
 

Latest revision as of 16:57, 3 July 2013

[edit]

This bacterium infects multiple types of hosts including herbivorous mammals such as livestock and is considered zoonotic however humans are a dead end host and do not become infectious.

Cutaneous: skin contact with spores from infected animals (95% of Cases; Most in Africa, Asia, and eastern Europe).
Gastrointestinal: eating poorly cooked meat/dairy from infected animal.
Inhalation: Inhalation of spores
Injectional: soft tissue infection associated with injection drug use
[1]
Anthrax is not contagious and cannot be transmitted from person-to-person. [2]

Case fatality ratios
Case Fatality Ratio Pathway/conditions Population References
1% Cutaneous with treatment General US Population [3]
20% Cutaneous without treatment General US population [3]
75% Inhalation despite treatment Not Reported [3]
89% Inhalation Occupationally Acquired: 20th century untreated [1]
45% 2001 US Attack Adult US [4]
14% (5 of 37) Cutaneous Children 1900-2005 [5]
60% Inhalation Children 1900-2005 [5]
65% (13 of 20) Gastrointestinal Children 1900-2005 [5]
100% Gastrointestinal Unreported [1]
100% (6 of 6) primary meningoencephalitis Children 1900-2005 [5]
100% (6 of 6) primary meningoencephalitis Children 1900-2005 [5]
1.5% (of 132) Not reported Hospitalized adults and children, Turkey 1986 to 2000 [6]
30% (3 of 10) Injectional Adults aged 23-53, UK [1]

|}

Incubation Times
Days Pathway Population Reference
0-1 Cutaneous Not Reported [3]
1-7 days Inhalation

Ingestion

Not Reported [3]
60 (max) Inhalation

Ingestion

Not Reported [3]
10 Days (SD: 8.67) Inhalation Sverdlovsk 1979 outbreak (70 cases) [2]

Duration of infectiousness and disease

Gastrointestinal: 10-14 days[1]

Symptomology

Cutaneous:

  • Primary skin lesion 3-5 days after infection is painless puriritic papule.
  • Lesion forms a necrotic vesicle leaving a black eschar surrounded by edma.
  • Eschar dries and sloughs in next 1-2 weeks.


Gastrointestinal:

  • Oral-pharyngeal form: oral or esophageal ulcer with regional lymphadenopathy edema and sepsis
  • Lower GI form: primary intestinal lesions predominantly in terminal ileum or cecum. Nausea, vomiting, malaise, bloody diarrhea, acute abdomen, and sepsis are common symptoms of the Lower GI form.


Inhalational:
Two-stages

  • 1: Flu-like symptoms including cough fever, fatigue that last from hours to a few days
  • 2: Rising fever, dyspnea, diaphoresis, shock. In advanced form, cyanosis and hypotension progress rapidly and death can occur within hours


Injectional:

  • Tissue swelling around the injection site
  • Abdominal symptoms[1]


Excretion Rates (see Exposure)

Spores are cleared from the lung at a rate between 8-14% per day. [2]

Immunity

Anthrax vaccination consists of 5 total intramuscular injections, followed by recommended annual boosters to maintain immunity. [3]

Gram +, aerobic, encapsulated, nonmotile. Exists in a dormant spore or an actively replicating vegetative rod form Extremely hardy spores can persist for years, even decades.[1]


References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Int Care Med
  2. ↑ 2.0 2.1 2.2 Brookmeyer, R., Johnson, E., & Barry, S. (2005). Modelling the incubation period of anthrax. Statistics in Medicine, 24(4), 531–542. doi:10.1002/sim. Full Text
  3. ↑ 3.0 3.1 3.2 3.3 3.4 3.5 3.6 CDC
  4. ↑ Holty J, Bravata D, Liu H, Olshen R, Mcdonald K, and Owens D. (2006) Systematic Review: A Century of Inhalational Anthrax Cases from 1900 to 2005. Annals of Internal Medicine. 144, 4. 270-280. Full Text
  5. ↑ 5.0 5.1 5.2 5.3 5.4 Bravata D, Holty J, Wang E, Lewis R, Wise P, McDonald K, and Owen D. (2007) Inhalational, Gastrointestinal, and Cutaneous Anthrax in Children. Arch Pediatr Adolesc Med. 161 (9): 896-905. Full Text
  6. ↑ Kaya A, Tasyaran M, Erol S, Ozkurt Z, and Ozkan B. (2002) Anthrax in Adults and Children: A Review of 132 Cases in Turkey. Eur J Clin Microbiol Infect Dis. 21: 258-261. Full Text
Retrieved from "http://qmrawiki.canr.msu.edu/index.php?title=Bacillus_anthracis&oldid=12148"