Furunculosis is an infection where furuncles are present over a period of weeks to months. Furunculosis is endemic in a number of Michigan waters but is not generally a problem in nature. A bacterial disease usually characterized by scabless, open sores, or furuncles, on the skin caused by Aeromonas salmonicida bacteria. Furunculosis is systemic in nature as it travels through the bloodstream and affects all parts of the body, especially the vital organs. It will multiply rapidly in the bloodstream and cause small blood vessels to rupture, allowing the bacteria to spread to surrounding tissue. Usually not contageous, but can be spread by direct contact. The fish should be quarantined and treated, especially if treating with antibiotics. During this slow development of the disease it is common to find large and small furuncles in the fish's muscles, that may erupt in lesions on the skin.
Furunculosis is very uncommon in young children, but it occurs more frequency after puberty. Transmission from individual to individual can occur if contact is made with drainage of pus from a furuncle. Development of the disease may be slow, and infection can be hidden for a long time. Infected fish without external symptoms are carriers and spread the disease, slowly increasing the mortality rate. In crowded hatchery settings, the disease can cause high mortalities if not recognized and treated at its onset. Warm moist compresses provide comfort and encourage localization and pointing of the abscess; apply three or four times daily for 20 minutes each time. With treatment, furuncles will heal in less time and symptoms will be less severe. A potential complication of treatment is that the pus that drains when the furuncle opens spontaneously may contaminate nearby skin, causing new furuncles.
Causes of Furunculosis
Common causes and risk factors of Furunculosis:
- Staphylococcus aureus.
Signs and Symptoms of Furunculosis
Sign and symptoms may include the following :
- Pustular rash.
- Cessation of feeding.
- Skin abscess.
- Darkening of body colour.
- Group of boils.
Treatment for Furunculosis
Treatment may include:
- Topical medication can be applied, such as hydrogen peroxide, or formaldehyde solutions, or used as a dip.
- Antibiotics, particularly those that can be absorbed internally.
- Warm moist compresses provide comfort and encourage localization and pointing of the abscess.
- Terramycin or Romet are often effective in treating furunculosis.