Opposition party Democratic Alliance (DA) Shadow Minister of Health Siviwe Gwarube said on Wednesday that Health Minister Dr Zweli Mkhize should step down from his role, pending the outcome of a Special Investigating Unit (SIU) probe into reports that his department irregularly awarded a R150-million contract to close associates of his. The SIU is investigating the 2019 contract in which Digital Vibes was appointed to provide communication services for government’s National Health Insurance and Covid-19 response.