A 30-year-old woman from country South Australia has been admitted to hospital after being diagnosed with meningococcal disease.
SA Health said the woman has the B strain of the disease and was in a stable condition on Tuesday.
Multiple people were identified as having been in contact with the patient and three people have received clearance antibiotics.
There have been five cases of meningococcal disease in SA so far this year, compared to eight at the same time last year.
Of the five cases, three have had the B strain, one had the W strain, and one had the Y strain.
The 101-year-old woman who contracted the W strain of the disease died earlier this year.
Meningococcal disease is a bacterial infection that can be fatal if not recognised early and appropriately treated.
The disease can affect all age groups, but is most common in children under five years of age and in young adults, aged 15 to 24 years.
A total of 34 cases were reported in 2018.