Melioidosis in Dogs

Melioidosis is a bacterial infection that affects both people and animals. It is caused by infection with Burkholderia pseudomallei, a bacterium found in soil and water in regions such as southeast Asia, northern Australia, and the South Pacific. Its exact range is not fully known because cases and outbreaks can also occur in other areas, especially after heavy rain, flooding, digging, or disruption of water systems.

Many animals can be affected, including sheep, goats, pigs, dogs, and cats, as well as people. Animals with weakened immune systems are more likely to become ill. Infection usually comes from the environment rather than from other animals. Bacteria can enter the body through skin wounds, ingestion of contaminated soil or the dead bodies of infected animals, or inhalation.

Signs vary widely, and some infections cause no symptoms at all. Disease can appear as abscesses (pockets of pus) or firm masses in one or multiple organs in the body. When infection enters through the skin, lesions can develop in distant parts of the body without an obvious infection site.

Melioidosis in dogs can involve bloodstream infection, fever, severe diarrhea, and pneumonia (lung infection). Skin lesions and inflammation of the lymph system can also occur. Long-term infection can affect many organs in the body and cause loss of appetite, muscle pain, swollen legs, and skin abscesses. Severe cases or those involving vital bodily organs can be fatal.

Diagnosis is made by identifying the bacteria in samples from lesions or bodily secretions, and sometimes through blood tests. Treatment is often long, expensive, and difficult. Human treatment protocols for melioidosis are generally more effective than standard veterinary antibiotic treatments. Relapse after treatment is possible, and the disease may suppress the immune system in dogs.

Prevention focuses on decreasing environmental exposure to the bacteria, such as by providing clean housing away from soil, using safe (filtered and chlorinated) drinking water, and limiting contact with contaminated soil, manure, and dead animals. Because melioidosis can infect people, precautions are important when handling infected animals. The bacteria can be present in wounds, secretions from the nose, milk, feces, and urine of infected animals.

Melioidosis is zoonotic, meaning it can be spread from animals to people, so strict cleanliness and safe handling practices are essential.