Mycobacterium marinum, associated with aquariums and aquatic environments, is typically found in which environment?

Mycobacterium marinum, associated with aquariums and aquatic environments, is typically found in which environment?

• A. Freshwater lakes
• B. Soil
• C. Human skin flora
• D. Salt or brackish water

Answer: (D)

Mycobacterium marinum is an environmental non-tuberculous mycobacterium that thrives in aquatic habitats. It is commonly associated with aquariums and other aquatic systems, particularly those with some salinity, such as salt or brackish water. This environmental niche explains why human infections often come from exposure to contaminated water or fish tanks, leading to skin infections after contact with aquarium water. Freshwater lakes and soil are not its typical reservoirs, and it is not part of normal human skin flora. Therefore, salt or brackish water best matches its usual environment.

Mycobacterium marinum is an environmental non-tuberculous mycobacterium that thrives in aquatic habitats. It is commonly associated with aquariums and other aquatic systems, particularly those with some salinity, such as salt or brackish water. This environmental niche explains why human infections often come from exposure to contaminated water or fish tanks, leading to skin infections after contact with aquarium water. Freshwater lakes and soil are not its typical reservoirs, and it is not part of normal human skin flora. Therefore, salt or brackish water best matches its usual environment.