ABC7’s More in the Morning crew spoke with Dr. Michael Kim about Mycobacterial Hand Infections. Mycobacterium marinum (M. marinum) is a slow-growing bacterium that can be found in both fresh and salt water around the world.
The risk of infection increases for people that are immuno-compromised or who have a scrape, cut or other skin abrasion that can serve as an entry site for the bacteria.
Symptoms of Mycobacterial Marinum Hand Infection
Symptoms of Mycobacterium marinum typically occur within 2 – 4 weeks of exposure; however, some cases have developed 2 – 4 months or longer after exposure due to the slow-growing nature of this bacterium. Symptoms may include:
- Slowly developed single or multiple localized skin lesions at the site where bacteria entered the body typically appear around two weeks after exposure. The lesions may be ulcerated, crusted or wart-like (verrucous) in appearance, and are initially not painful. Over weeks or months, they may spread proximally up the involved limb.
- Swelling of the nearby lymph nodes
- Infection progression in more advanced infections from superficial involvement of the skin to invade deeper structures including tendons and the sheaths through which the tendons pass
- Invasion of the bones, which is less common.
Preventative Measures
You can take the following precautions to prevent or reduce the risk of Mycobacterium marinum infection:
- Minimize or eliminate exposure to fresh or salt water when open cuts, scrapes or abrasions exist on the skin.
- Be sure to cover any open cuts, scrapes or abrasions, and wear heavy or waterproof gloves when cleaning fish, fish tanks or equipment.
- Wash hands and forearms after direct contact with fish, fresh or salt water.
- Maintain swimming pools with adequate chlorination.
There has been no evidence that drinking fresh or salt water will cause infection. Additionally, there has not been any evidence that eating infected fish will cause M. marinum infection.