Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

Epidemiology of brucellosis in ruminants: the basics and dynamics of the disease


Published on

Presented by John B. Kaneene at a workshop on an integrated approach to controlling brucellosis in Africa, Addis Ababa, Ethiopia, 29-31 January 2013.

  • Be the first to comment

Epidemiology of brucellosis in ruminants: the basics and dynamics of the disease

  1. 1. Epidemiology of Brucellosis in Ruminants:the Basics and Dynamics of the DiseaseProfessor John B. KaneeneDVM, MPH, PhD, FAESCenter for Comparative EpidemiologyMichigan State UniversityWorkshop: An Integrated Approach to ControllingBrucellosis in Africa, Addis Ababa, 29-31 January2013
  2. 2.  Basic Epidemiology of Brucellosis Reservoirs and Routes of Transmission Outbreak Investigations Surveillance and Control Programs Summary2Presentation Outline
  3. 3.  Host-Agent-Environment Host species: most mammalsHoofstock: cattle, goats, sheepSwine and other mammals Agents: Brucella spp.Host preferences, but not specific Environmental conditions:Allows direct contact with materials contaminatedwhen Brucella are shed3Basic Epidemiology of Brucellosis
  4. 4.  Reservoir hosts: Host allows pathogen to survive, grow, andmultiply without compromising significantlyreproduction and survival Maintains infection within their speciespopulation Capable of transmitting infection to other species4Reservoirs of Brucellosis
  5. 5.  Wildlife Reservoir of Brucella in Africa Primary Livestock Reservoirs of Brucella5Reservoirs of Brucellosis B. abortus:Cattle, Buffalo B. melitensisGoatsSheep B. abortus:African Buffalo B. ovisSheep B. suisSwine
  6. 6.  Brucella in Africa Wildlife6Reservoirs of Brucellosis Bovidae* African buffalo* Bushbuck Eland Impala Kob Lechwe Bovidae (cont). Waterbuck Wildebeeste Others: Giraffe Zebra Hippopotamus* - high potential for reservoir status
  7. 7.  Primary Routes of Shedding for Brucellosis Urogential systemUterine discharges: HIGHLY INFECTIOUSMilkSemen Shedding not constant, consistent7Routes of Transmission
  8. 8.  Routes of Transmission for Brucellosis Ingestion of contaminated materials Contact throughMucous membranesOpen woundsConjunctiva Vertical transmission – questionable8Routes of Transmission
  9. 9.  Shedding Abortion – reproductive fluids MilkAfter abortionContinue through life of the animal Transmission Ingestion of milk Ingestion of contaminated materials9Maintenance of Brucellosis
  10. 10.  Steps for conducting outbreak investigations Establish and verify existence of outbreakReported casesRoutine surveillance Define and identify casesConsistent case definitionLaboratory confirmation10Outbreak Investigations
  11. 11.  Steps for conducting outbreak investigations Epidemiological InvestigationData collection: demographics, clinical data, riskfactorsExamination of cases and premisesCharacterize outbreak Populations affected Geographic extent Dates and Trends over Time11Outbreak Investigations
  12. 12.  Steps for conducting outbreak investigations Formulate & evaluate hypothesesSource of infection Primary case Imported casesModes of Transmission and Exposures ‘Abortion storms’ Venereal exposure12Outbreak Investigations
  13. 13.  Outbreak Control Control measuresControl source of pathogen – Identify infected animalsInterrupt transmission – Quarantine, cullingControl host response to exposure – vaccination Monitoring to evaluate effectiveness of controlmeasuresDirected Surveillance Passive and Active Surveillance13Outbreak Investigations
  14. 14. 1. Brucella spp. have many domestic andwildlife reservoirs2. Outbreak Investigation is an importanttool for studying disease dynamics14Summary
  15. 15. 3. Establishing surveillance systems is a key tomonitoring disease status and planning forcontrol measures4. In both outbreak investigation andsurveillance, use of appropriate diagnostictests is critical15Summary (cont.)
  16. 16. THANK YOU!16