Fungal infections: sporotrichosis

Sporotrichosis is an infection caused by the fungus Sporothrix schenckii. It usually affects the skin, presenting as a red inflamed lump or skin sore at the body site exposed to the fungus. Further lumps can then form around the affected area and along the lymph ducts, creating a series of cord-like lumps.

Incubation period

Skin lesions occur 1 week to 3 months after exposure to the fungus.

How it is spread

Sporotrichosis occurs following direct contact with substances contaminated with the fungus. Substances commonly contaminated include plant or organic matter such as hay, sphagnum moss, thorny plants, soil or timber. The fungus enters the body through a break in the skin, such as those caused by barbs or thorns.

While sporotrichosis most commonly results from environmental exposure, on rare occasions infection has been shown following direct contact with an infected animal, most commonly cats. Sporotrichosis is not spread from person to person.

Who is at risk

Anyone handling infected organic matter can develop sporotrichosis. People regularly handling plant or organic matter such as keen gardeners or nursery workers are at increased risk of infection due to greater opportunity for exposure to the fungus.

Immunosuppressed people are more susceptible to sporotrichosis. In these individuals there is a risk of more severe disease, potentially affecting other parts the body such as the joints or lungs.

What to do if you suspect infection with sporotrichosis

People who have non-healing skin lesions or a series of red lumps under the skin should seek advice from their doctor. 

A biopsy of the skin taken from the affected area confirms diagnosis. The skin lesions can look like bacterial infections, so it is important to confirm the diagnosis by laboratory testing to guide appropriate treatment.

Treatment

Sporotrichosis can be treated with prescription anti-fungal tablets. Skin lesions caused by sporotrichosis are often slow to heal; hence treatment may extend to weeks or months.

Prevention

People handling plant or organic materials such as hay or moss should wear protective clothing such as long-sleeved shirts, long pants, closed-in shoes and gloves.

In Australia, hay has been implicated as the source of infection in multiple outbreaks. Hay suppliers are advised to ensure hay is dry prior to baling and kept free of moisture as warm, moist conditions promote growth of the fungus when present.

Contact

For more information contact the Centre for Disease Control in your region.

Last updated: 27 June 2017