A young woman is in a stable condition in hospital with meningococcal infection - the second report in two days.
SA Health has identified multiple people who had contact with the 18-year-old woman from metropolitan Adelaide.
Six are receiving clearance antibiotics.
On Thursday, a 18 month old was taken to hospital with the B strain of the potentially deadly disease.
There have been 32 cases of meningococcal infection in South Australia so far this year, compared to 35 cases at the same time last year.
No connection has been established between the latest case and any previous cases.
Of the 32, 26 have been the B strain, four the W strain and two the Y strain.
A total of 36 cases were reported last year — 22 of the B strain, 11 of the W strain and three of the Y strain.