A private laboratory that initially said an SABC staff member had contracted Covid-19 but later confirmed he was negative explained on Thursday what went wrong.

The SABC released a precautionary communiqué and temporarily closed its Durban offices based on official lab results presented to its employee.

“The employee has since been alerted by the lab in question that an error occurred during the initial testing and the employee was presented with new test results, whose outcome was negative,” said the broadcaster on Wednesday.

Explaining what happened, Pierre du Randt, chief pathologist of JDJ Diagnostics, told radio 702 that some samples needed to be tested more than once to ensure there was no false positive or false negative, but this did not happen in this case.

In this case, a sample was taken and processed, and returned "very weakly positive".

"So what JDJ Diagnostics does at its own expense is actually take that sample and test it a couple of times to see whether it is a false positive or a false negative. The [lab] employee released the presumptive result without asking a pathologist first and that is where the system failed," he said.

The SABC said the initial positive result had a serious impact on the organisation, including the temporary closure of its office and some staff members urgently having to undergo testing.

The office will resume its normal operations on Friday.