Brucellosis in Livestock: A Kenya Farmer Guide

What is Brucellosis?

Brucellosis (also called Contagious Abortion or Bang's Disease) is a bacterial infection caused by Brucella abortus (cattle), Brucella melitensis (goats/sheep), and Brucella suis (pigs). It causes reproductive losses in animals and is a serious PUBLIC HEALTH RISK - it can infect humans (called Undulant Fever).

CRITICAL: Zoonotic Disease

Brucellosis spreads from animals to humans. NEVER:

• Handle aborted material without gloves
• Drink raw (unpasteurized) milk from infected herds
• Eat raw meat from infected animals
• Allow children near aborted fetuses or placentas

Human symptoms: Recurring fever, joint pain, fatigue, headache. If you suspect human infection: Visit hospital immediately.

How Animals Get Infected

• Direct contact with aborted fetus, placenta, birth fluids
• Drinking contaminated water
• Licking infected surfaces (feeding troughs)
• Bull-to-cow transmission during mating
• Milk - calves/kids infected through milk

Symptoms in Animals

Cattle (Brucella abortus):

• Abortion in last trimester (7-9 months) - KEY sign
• Retained placenta after normal birth
• Weak/stillborn calves
• Reduced milk production
• Repeat breeding/infertility
• Bulls: swollen, painful testicles (orchitis)

Goats/Sheep (Brucella melitensis):

• Abortion in last 4 weeks of pregnancy
• Arthritis, lameness
• Mastitis (swollen udder)

Pigs (Brucella suis):

• Abortion at any stage
• Infertility in sows
• Lameness, swollen joints

Diagnosis

• Laboratory: Blood test (Rose Bengal Test, ELISA)
• Milk ring test for herds
• Do NOT attempt diagnosis yourself - contact vet

Treatment

There is NO practical treatment for animals. Infected animals should be:

1. Isolated immediately
2. Reported to County Veterinary Department (LEGAL requirement)
3. Test-and-slaughter policy applies in Kenya

Prevention

Vaccination (Most Effective):

Cattle:

• S19 Vaccine (Brucella abortus S19)
• Given to heifers: 4-8 months old ONLY
• One vaccination = lifelong protection
• Do NOT vaccinate pregnant cows or adult bulls
• Available from KEVEVAPI and agrovet shops

Goats:

• Rev-1 Vaccine (Brucella melitensis Rev-1)
• Given to female kids: 3-6 months old
• One vaccination provides long immunity

Herd Management:

• Test all new animals before introducing to herd
• Quarantine new animals for 30 days + test
• Never buy animals from unknown sources
• Dispose of aborted material safely: Burn or bury deep (2 metres) with lime
• Disinfect areas where abortion occurred: Formalin 5% or Caustic soda solution

Milk Safety:

• Always pasteurize milk (72C for 15 seconds) or boil before consumption/sale
• Do NOT sell raw milk from herds with known abortion history

Legal Requirements in Kenya

• Brucellosis is a NOTIFIABLE DISEASE in Kenya
• You MUST report suspected cases to your County Veterinary Officer
• Failure to report is a criminal offense
• Government may conduct compulsory testing
• Compensation may be available for slaughtered animals

Economic Impact

• Abortion losses: cost of lost calf + reduced milk
• Per aborted calf: KSh 20,000-80,000 loss
• Reduced fertility: repeat breeding costs
• Herd productivity reduction: 15-25%
• Human medical costs if farmers infected

Key Message for Farmers

One aborted fetus can infect your entire herd and your family. Vaccinate your heifers at 4-8 months. Test before buying. Report abortions immediately.