B. canis

An overview of Brucella canis, its characteristics, transmission, and impact on health.

Brucella canis is a species of the genus Brucella, which is a group of gram-negative bacteria known to cause brucellosis in various animal species and humans. B. canis specifically affects dogs and can occasionally infect humans, leading to a zoonotic disease.

Characteristics

Brucella canis is a small, non-motile, gram-negative coccobacillus. It is an intracellular pathogen, meaning it can survive and replicate within host cells. This bacterium is aerobic and does not form spores. B. canis is known for its ability to evade the host's immune system, leading to chronic infections.

Transmission

The primary mode of transmission of B. canis is through direct contact with infected animals or their secretions. In dogs, the bacterium is often spread through:

• Contact with aborted fetuses or vaginal discharges from infected bitches.
• Semen from infected male dogs during mating.
• Contaminated surfaces or materials, such as bedding or food bowls.

Humans can become infected through:

• Direct contact with infected dogs or their secretions.
• Laboratory exposure to the bacterium.

Symptoms

In dogs, B. canis infection can lead to reproductive issues such as:

• Abortion in pregnant bitches, typically occurring in the last trimester.
• Infertility in both male and female dogs.
• Orchitis and epididymitis in male dogs.

In humans, symptoms of B. canis infection are often non-specific and may include:

• Fever
• Fatigue
• Joint and muscle pain
• Headaches

Diagnosis

Diagnosis of B. canis infection in dogs is typically done through serological tests, such as the rapid slide agglutination test (RSAT) or the tube agglutination test (TAT). Confirmation can be achieved by culturing the bacteria from blood or tissue samples.

In humans, diagnosis involves serological testing and culture of blood samples.

Treatment

Treatment of B. canis infection in dogs can be challenging due to the bacterium's intracellular nature. Long-term antibiotic therapy, often with a combination of drugs such as doxycycline and enrofloxacin, is required. Infected dogs may remain carriers even after treatment.

In humans, treatment typically involves a combination of antibiotics, such as doxycycline and rifampin, for several weeks.

Prevention

Preventive measures include:

• Regular screening of breeding dogs for B. canis infection.
• Isolation and treatment of infected animals.
• Good hygiene practices when handling dogs, especially in breeding facilities.

Also see

• Brucellosis
• Zoonosis
• Gram-negative bacteria
• Intracellular pathogens