21 - brucellosis

Question 1

List the Brucella sp. that infect humans. Know the relative pathogenicity of common species.

Answer 1

B. melitensis > B. suis > B. abortus > B. canis

Question 2

Be aware of the major risk factors for human brucellosis including food borne and occupational factors. How do most US citizens acquire?

Answer 2

Most: ingestion of raw milk and unpasteurized dairy products
Contact with infected animals or tissues (esp fetus, fetal membranes, and vaginal discharges)
Airborne infection has occurred in labs

Question 3

Be able to advise clients on the risks for human Br. canis infection and the handling of an individual dog or group (kennel) problems.

Answer 3

• risk to humans is low
• eliminate infected animals from kennels
• avoid contact with infected animals or use protective gloves
• disinfect kennels
• no immunizing agent available

kennel problems

• quarantine
• continued testing until at least 3 consecutive monthly tests fail to identify infected animals
• after that, quarterly or biannual testing
• strict isolation, sanitation, with or without abx tx have failed to protect uninfected animals

if going to give therapy (doxycycline and streptomycin best – relapses common) recommend dog be isolated and neutered to reduce probablility of transmission – screening of other dogs in close contact is recommended

Question 4

(brucellosis)

Be able to describe methods to control and prevent human infections.

Answer 4

• Pasteurization of all milk and dairy products
• Avoid contact with known infected tissues
• Eradication of animal reservoir
• Provide adequate ventilation and reduce aerosol production in slaughter and rendering plants
• Use protective clothing when assisting animals during parturition or when disposing of contaminated bedding and products of abortion

Question 5

What is the current status of the eradication programs for bovine and porcine brucellosis

Answer 5

• Bovine – brucellosis Everywhere has been free for a year (in 2013), some longer – doing slaughter surveillance
• Swine – 100 cases a year (0.5 cases per 100,000), mostly in texas, California, Virginia, florida

Currently they are doing a slaughter surveillance program

There are different state classes

infection free

“A” infection rate < 0.25%; test cattle before export

“B” infection rate between 0.25% and 1.5%; test before interstate movement

“C” infection rate is greater than 1.5%; test 2x before and once after transport.