Three men have tested positive for mpox (formerly known as monkeypox) in South Australia, prompting health authorities to encourage vaccination against the virus.

SA Health said the men were aged in their 20s, 30s and 50s.

Communicable Disease Control Branch deputy director Dr Louise Flood said the risk of transmission to the wider community was low.

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The men are the first three cases of mpox in South Australia this year.

There were no cases last year, and two cases recorded in 2022.

Nationally, there have been 67 cases of mpox this year, with 45 of these cases reported in Victoria.

Most people recover from the virus within a few weeks, but some may develop severe illness and require hospitalisation.

Symptoms of mpox include a rash, fever, sore throat, headache, tiredness, muscle aches and swollen lymph nodes.

The rash may appear as vesicles, pustules or ulcers.

Mpox can spread through contact with contaminated items or surfaces, as well as prolonged or intimate skin-to-skin contact.

“People with mpox are considered infectious from the time they develop their first symptoms and until rash lesions have crusted, scabs have fallen off and a fresh layer of skin has formed underneath,” an SA Health spokesperson said.

Free vaccination for mpox is available to people who are a close contact of an existing case, sex workers and sexually active gay or bisexual men.