A health professional holds a swab test for the COVID-19 coronavirus at a drive-through testing site outside the Lancet Laboratories facilities in Johannesburg.
Two patients are currently in ICU in private hospitals.
Three doctors -- one in Limpopo, Mpumalanga and the Free State -- have tested positive.
Mkhize said there are no fatalities and that all patients are improving.
He said the largest number of scattered cases are in Johannesburg. In the Western Cape, scattered cases are around Cape Town.
Mkhize says the health department will increase testing facilities, but there will be strict criteria as to who can get tested.
"We test those with a history of symptoms and a history of contact and travel," he said.
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The NICD has another Clinician Hotline to improve #COVID19 communication and support for healthcare providers. The Clinician Hotline is 0800 11 1131, operating 24 hrs. The Public Hotline is 0800 029 999 also operating 24hrs.