brucellosis

BRUCELLOSIS

DR. AREEJ M. N.

Epidemiology

Epidemiology
Worldwide zoonosis
Only 17 countries declared brucellosis free1986
Six species
1. B.abortus - mainly cattle
2. B.melitensis - sheeps & goats
3. B.suis - pigs
4. B. canis - dogs
5. B. ovis - sheep (not human pathogen)
6. B. neotomae - desert wood rat (not human pathogen)
B. melitensis -- most common worldwide


Populations at Risk
Occupational disease
Cattle ranchers/dairy farmers
Veterinarians
Meat inspectors
Lab workers
Hunters
Travelers
Consumers
Unpasteurized dairy products
Center for Food Security and Public Health, Iowa State University, 2012

Brucella melitensis

Distribution
Mediterranean, Middle East, Central Asia, Central America
Incidence
Mediterranean, Middle East
78 cases/100,000 people/yr
Arabic Peninsula
20% seroprevalence; 2% active cases
100 to 200 U.S. cases annually
Unpasteurized cheeses
Center for Food Security and Public Health, Iowa State University, 2012

Epidemiology in Saudi Arabia

Endemic disease
Mostly B. melitensis & b. abortus.
No clear figures about incidence & prevalence.
Incidence : 5.4 per 1000 per year.
Prevalence : 8.6 - 38 % - some regions.

Transmission

Transmission
Zoonosis affecting domestic animals.
Concentrated in milk, urine, genital organs.
ROUTES OF TRANSMISSION
Oral : unpasteurised milk & products raw milk or meat.
Respiratory: lab workers.
Skin: accidental penetration or abrasion
- at risk farmers & veterinarians.
Other routes:
Conjunctival, Blood transfusion, Transplacental, ? person to person.


Clinical Manifestations
Incubation period: variable 2- 8 wks.
Presentation: acute 50% & insidious 50%
Sx & signs not specific.
Can affect any organ.
Common nonspecific Sx:
- fever with rigors.
- sweats, malaise, anorexia.
- headache, back pain.

Diagnosis in Humans

Isolation of organism
Blood, bone marrow, other tissues
Serum agglutination test
Four-fold or greater rise in titer
Samples 2 weeks apart
Immunofluorescence
Organism in clinical specimens
PCR
Center for Food Security and Public Health, Iowa State University, 2012


Treatment
Drugs against Brucella
Tetracyclines
Aminoglycosides
Streptomycin since 1947
Gentamicin
Netilmicin
Rifampicin
Quinolones - ciprofloxacin
?3rd generation cephalosporins

Treatment

Drugs against Brucella
Treatment for uncomplicated Brucellosis
Stremptomycin + Doxycycline for 6 weeks
? TMP/SMX + Doxycycline for 6 weeks
WHO recommendation 1986
Rifampicin + Doxycycline for 6 weeks
Treatment of complicated Brucellosis
Endocarditis, meningitis
No uniform agreement
Usually 3 antibrucella drugs for 3 months


Complications of Brucellosis
Most common
Arthritis, spondylitis, epididymo-orchitis, chronic fatigue
Neurological
5% of cases
Other
Ocular, cardiovascular, additional organs and tissues
Center for Food Security and Public Health, Iowa State University, 2012

Congenital Brucellosis

Variable symptoms
Premature delivery
Low birth weight
Fever
Failure to thrive
Jaundice
Hepatomegaly
Splenomegaly
Abortion risk unclear
Center for Food Security and Public Health, Iowa State University, 2012

Control of disease in domestic animals

immunization using B. abortus strain 19 and B. melitensis strain Rev 1
Routine pasteurization of milk
In labs strict biosafety precautions
Prevention