Red mullet in humans (Baker-Rosenbach erysipeloid)

What is it about ?

“Pork mullet” is a skin condition caused by the bacteria Erysipelothrix rhusiopathiae. This bacterium is found mainly in certain animals such as pigs, fish and birds. Humans can be infected through a wound. Pork mullet is a rare occupational disease in people who work with products that contain raw fish and raw meat, such as farmers, butchers, fishermen and veterinarians.

What is its frequency?

This bacteria is found everywhere in the environment. Even healthy animals can be carriers. Carriers are not sick, but spread the bacteria through their feces. The bacteria then enter humans (or other animals) through injury or erosion of the skin. Contamination is common, but it does not always lead to infection.

How to recognize it?

In case of erysipeloid, well-defined purplish-red patches appear on the skin, usually on the hands. They are often accompanied by pain and severe itching. A tingling sensation and painful swelling may occur. There is no formation of pus. The spots can remain present for a few weeks to several months. Then the skin turns brown and peels (scaly skin). Sometimes the infection spreads to the lymph nodes, especially the armpits. These nodes are then painful and swollen. Fever, a general feeling of being sick or other physical symptoms are rare, unless the bacteria get into the blood (sepsis). In this case, the evolution is more severe. Fortunately, this situation is very rare.

How is the diagnosis made?

Usually, the doctor will diagnose erysipeloid based on your story and looking at the characteristic rash on your skin. But in case of doubt, a skin sample can be taken (biopsy) for additional examinations. This precaution is seldom necessary, however.

What can you do ?

The development of pork mullet is generally benign; the affection resolves spontaneously. To prevent contamination and disease, always protect hands with gloves when touching animals, especially if you are injured. Cover wounds, always clean and disinfect an open wound. There is a vaccine for pigs, but it is not compulsory for breeders.

What can your doctor do?

Usually, the erysipeloid goes away on its own and without treatment. Treatment with antibiotics (eg penicillin) may shorten the duration of the illness.

Want to know more?

• Hand hygiene – SPF Public health, food chain safety and the environment

Source

Foreign clinical practice guide ‘Cutaneous erysipeloid’ (2000), updated on 11.02.2016 and adapted to the Belgian context on 12.09.2019 – ebpracticenet