Bioterrorist Bioterrorist Agents: Agents:

BrucellosisBrucellosis

Learning ObjectivesLearning Objectives

Become familiar with the following Become familiar with the following aspects of Brucellosis:aspects of Brucellosis: Epidemiology Epidemiology TransmissionTransmission Clinical featuresClinical features Diagnosis Diagnosis TreatmentTreatment PreventionPrevention

BackgroundBackground

Brucella melitensisBrucella melitensis discovered by discovered by Bruce in 1887Bruce in 1887

Types: Types: B. melitensis, abortus, suis, B. melitensis, abortus, suis, neotomae, ovis, canisneotomae, ovis, canis, and types , and types infecting marine mammals infecting marine mammals

Pathogenic types in humans - Pathogenic types in humans - B. B. melitensismelitensis, , abortusabortus, , canis canis and and suissuis

Zoonotic diseaseZoonotic disease

Brucellosis- definitionBrucellosis- definition

A multisystem disease with a broad A multisystem disease with a broad range of symptoms including acute range of symptoms including acute or insidious onset of fever, night or insidious onset of fever, night sweats, undue fatigue, anorexia, sweats, undue fatigue, anorexia, weight loss, headache and arthralgiaweight loss, headache and arthralgia

EpidemiologyEpidemiology

Incidence in US: <0.5 cases per Incidence in US: <0.5 cases per 100,000 100,000 primarily primarily B. melitensis B. melitensis

Most cases in the US are reported Most cases in the US are reported from California, Florida, Texas and from California, Florida, Texas and VirginiaVirginia

High risk areas: High risk areas: Mediterranean Mediterranean Basin, South and Central America, Basin, South and Central America, Eastern Europe, Asia, Africa , the Eastern Europe, Asia, Africa , the Caribbean and the Middle East. Caribbean and the Middle East.

TransmissionTransmission

Three methods of transmission:Three methods of transmission:1.1. Ingestion –unpasteurized milk or dairy Ingestion –unpasteurized milk or dairy

products. Ingestion is most common products. Ingestion is most common method of transmission.method of transmission.

2.2. Inhalation – breathing in the Inhalation – breathing in the organism. Lab workers are high risk.organism. Lab workers are high risk.

3.3. Wound contamination –high risk Wound contamination –high risk occupations include hunters, occupations include hunters, slaughterhouse workers, meat packing slaughterhouse workers, meat packing plant workers and veterinariansplant workers and veterinarians

Potential For Intentional Potential For Intentional Harm?Harm?

CDC Category B agentCDC Category B agent Most likely route of intentional exposure: Most likely route of intentional exposure:

Respiratory Respiratory Could also happen via contamination of Could also happen via contamination of

food/drinkfood/drink Identify intentional exposures as any BT Identify intentional exposures as any BT

agent:agent: Common SourceCommon Source Unlikely patientsUnlikely patients Unlikely SeasonUnlikely Season Multiple PatientsMultiple Patients Geographic correlationGeographic correlation

Case DefinitionCase Definition Clinical illness with fever, night sweats, fatigue, Clinical illness with fever, night sweats, fatigue,

anorexia, weight loss, headache and arthralgiaanorexia, weight loss, headache and arthralgia Laboratory criteria for diagnosis:Laboratory criteria for diagnosis:

Isolation of Isolation of BrucellaBrucella sp. from a clinical sp. from a clinical specimen, or specimen, or

Fourfold or greater rise in Fourfold or greater rise in BrucellaBrucella agglutination titer between acute- and agglutination titer between acute- and convalescent-phase serum specimens convalescent-phase serum specimens obtained greater than or equal to 2 weeks obtained greater than or equal to 2 weeks apart and studied at the same laboratory, or apart and studied at the same laboratory, or

Demonstration by immunofluorescence of Demonstration by immunofluorescence of BrucellaBrucella sp. in a clinical specimen sp. in a clinical specimen

Case classificationCase classification

Probable:Probable: clinically compatible case clinically compatible case with an epidemiologic link with an epidemiologic link

Confirmed:Confirmed: clinically compatible case clinically compatible case that is laboratory confirmedthat is laboratory confirmed

Clinical FeaturesClinical Features

Flu-like symptoms:"undulant" fever, Flu-like symptoms:"undulant" fever, headache, chills, myalgias, arthralgias, headache, chills, myalgias, arthralgias, weakness and malaise weakness and malaise

Most recover entirely within 3 to 12 Most recover entirely within 3 to 12 months months

Some develop ill-defined chronic Some develop ill-defined chronic syndromesyndrome

Possible complications: arthritis, uveitis, Possible complications: arthritis, uveitis, sacroiliitis, spondylitis (10% of cases), sacroiliitis, spondylitis (10% of cases), meningitis (5%), and epididymoorchitismeningitis (5%), and epididymoorchitis

TreatmentTreatment

Six week course of a combination of Six week course of a combination of antibiotics. antibiotics.

Doxycycline and rifampin or Doxycycline and rifampin or doxycyclin and streptomycin doxycyclin and streptomycin

Prevention/Infection Prevention/Infection ControlControl

Pasteurizing milk and dairy productsPasteurizing milk and dairy products Eradicating infection from herds and Eradicating infection from herds and

flocksflocks Observing safety precautions for Observing safety precautions for

occupational exposures includingoccupational exposures including rubber bootsrubber boots wearing impermeable clothing, wearing impermeable clothing, gloves and face masks gloves and face masks practicing good personal hygiene practicing good personal hygiene

Case ReportsCase Reports

Suspected Brucellosis Case Prompts Investigation of Possible Bioterrorism-Related Activity

MMWR Morb Mortal Wkly Rep MMWR Morb Mortal Wkly Rep 2000: 49(23)2000: 49(23)http://www.http://www.cdccdc..govgov//mmwrmmwr/PDF/wk/mm4923./PDF/wk/mm4923.pdfpdf

ResourcesResources

CDC CDC Emergency Preparedness and Emergency Preparedness and ResponseResponse

www.bt.cdc.gov/agent/brucellosis/index.aspwww.bt.cdc.gov/agent/brucellosis/index.asp

USDA, APHIS, Veterinary ServicesUSDA, APHIS, Veterinary Services

www.aphis.usda.gov/vs/nahps/brucellosiswww.aphis.usda.gov/vs/nahps/brucellosis

Special thanks to Altoon Dweck, MD, MPH, Johns Hopkins Preventive Medicine Resident