South Australia's 'patient zero' who sent the state into a strict lockdown is identified as Peppers Hotel security guard

A security guard at the Peppers Hotel has been identified as South Australia's 'patient zero' which ultimately saw the state plunged into a strict lockdown.

Health authorities confirmed on Wednesday the security guard had been the first to contract coronavirus after it was initially believed the outbreak came from an infected cleaner.

Premier Steven Marshall said CCTV taken from the Adelaide hotel confirmed that no staff had been in the wrong place at the wrong time.

Chief Public Health Officer Professor Nicola Spurrier said authorities are yet to determine how the virus was transmitted from a returned traveller to a staff member.  

A security guard at the Peppers Hotel in Adelaide has been identified as the 'patient zero' in the recent outbreak of coronavirus cases in South Australia

The outbreak has been linked to 29 cases in the state's Parafield cluster.

'There was also absolutely no incidents of staff going into the travellers' rooms. And certainly no inappropriate behaviour at all,' Dr Spurrier said. 

More to come.