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					BRUCELLA INTRODUCTION
           Brucella


                     Sir David Bruce isolated
                  Micrococcus melitensis from a
                  British soldier who died from
                     Maltese fever in Malta.




                  The Micrococcus of Malta Fever.
                  Practitioner, 1888, 40: 241-249.

Sir David Bruce
 (1855 - 1931)
           Classification of Brucella
Bacteria, Proteobacteria, a-Proteobacteria, Rhizobiales, Brucellaceae

                                         Species             Host

                                      B. abortus      cattle, human
                                      B. canis        dogs, foxes,
                                                      coyotes, human
                                      B. melitensis   sheep, goats,
                                                      human
                                      B. neotomae     desert wood rats
                                      B. ovis         rams
                                      B. suis         pigs, human
Gram negative, cocco-bacillus;
facultative intracellular bacterium

     Brucella listed as CDC and NIH priority category B pathogen
      Acquisition of Brucella Infection

                 Infects       Regional
   Entry                                            Systemic
                               Lymph                 Spread
                phagocytic      Nodes
                   cells


                                                  Liver, spleen,
                                                  other lymph
   Abortion                   Infection
                                                  nodes; uterus
                                                  in ungulates

Secretions, tissues,         Milk, cheese
       fetus                 & secretions


   Transmission to other vertebrates = Zoonosis
      Brucellosis in Vertebrates

 Animals:
   • Chronic   infection leading to abortion and
     infertility
   • Clinical signs & symptoms vary with species
      - metritis, spondylitis, lameness, paralysis
      - testicular swelling, lympadenitis, splenitis
 Humans:
   • Clinical signs & symptoms: fever (Undulant Fever)
     anorexia, back pain, fatigue, malaise, myalgia,
     sweats, weight loss.
   • Mortality rate is low; abortions NOT common
   • Clinical manifestations - a lot, including reactive
     arthritis (a type of spondylitis)
Brucellosis in livestock




  Global Livestock Production and Health Atlas,
 Animal Production and Health Division, 2006, FAO
               Brucella Genomes

                              Highly similar

    Large                  - B. melitensis, B. abortus & B. suis
chromosome I                 genomes are completely
   ~ 2.1 Mb                  sequenced; B. ovis is pending

                           - have 2 chromosomes

                           - contain about 3200 ORFs

                           - more than 90% of annotated
               Small         genes share 95-100% homology
           chromosome II
              ~ 1.2 Mb
                           - most of the differentiating genes
                             are located in 6 large islands
        Brucella can be intentionally
         released for bioterrorism
Brucella organisms could be released in aerosol form, by accidental spills of culture suspensions
    or live vaccines, or in liquids such as dairy products or water. Brucellosis has fairly low
    fatality rate, but could be used as an incapacitating agent, as the disease tends to be
    chronic, requiring prolonged treatment


    2. Emergency Contact: Local health departments and local law enforcement agencies
    should be contacted in the event of accidental or intentional release of Brucella
    species(Website 3).


    3. Delivery Mechanism: Brucella organisms could be aerosolized and released at infectious
    doses. 10-500 organisms in aerosol form constitute an infectious dose.


    4. Containment: Most commercial disinfectants are effective at killing or neutralizing
    Brucella organisms.

        http://www.nigms.nih.gov/News/Reports/biodefense.htm
   Brucella intentional release modeling
   Goal: See how is used, and how to possibly prevent and contain it.


Create new terms:
Planned process: Brucella intentional release; Brucella aerosolization; Brucella infectious dose
    (means: a dose that can induce brucellosis in a host.)
Input: aerosolized Brucella
Output:
Planned objective:


Term: Brucella containment
Term: Brucella intentional release route ??


2. Emergency Contact: Local health departments and local law enforcement agencies should
    be contacted in the event of accidental or intentional release of Brucella species(Website 3).
    3. Delivery Mechanism: Brucella organisms could be aerosolized and released at infectious
    doses. 10-500 organisms in aerosol form constitute an infectious dose.
    4. Containment: Most commercial disinfectants are effective at killing or neutralizing
    Brucella organisms.
     http://www.nigms.nih.gov/News/Reports/biodefense.htm
                               bearer_of                                                                                             has_part
                                                                              is_realized_by                                                       abortion
              B.abortus                    cattle brucellosis pathogen role                    cattle brucellosis
                                                                                                                                                   process
                                                                                               disease course

                                                                                                                    is_realized_by
brucellosis patient                  Brucella-contaminated milk
                                                                                          bearer_of                           is_a
                                                                resides_in
                      Drink…                                                                           cattle brucellosis            disposition


                       milk producing function                 Brucella-infected cow
                                                  bearer_of




                                                                                             is_a
                                                                   B. abortus infection               Brucella infection

                                                           is_realized_by
                                           bearer_of                            bearer_of
                                 human                 Brucellosis host                        Cow


                                                   Brucella-contaminated milk




  NOTES:
  •      We don’t have ‘resides_in’ relation.
  •      Focus: brucellosis is a zoonotic disease, it can infect both human and animals.

				
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posted:11/3/2011
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