The team will undergo further PCR tests during the day and the outcome of these tests will determine whether the game will go ahead or not.
Four more “close contacts” – two players and two members of staff – are being isolated and assessed at the team hotel.
The team made the announcement in a statement on Wednesday afternoon and if the game does go ahead it will take place at 8pm and not 7pm as initially planned.
“The British & Irish Lions can confirm that a member of its management team has tested positive for Covid-19 following a lateral flow test as part of the Tour screening programme which took place on Wednesday 7 July,” the statement read.
“The individual and four close contacts – including two players and two members of staff – are being isolated and assessed at the team hotel. All members of the touring party have since been PCR tested.
“This evening’s game against the Cell C Sharks at Emirates Airline Park will still take place provided the subsequent round of PCR testing returns negative results later this afternoon. Should this be the case, the kick-off time for tonight’s game will be adjusted to 8pm (SAST) / 7pm (BST).
“We have followed all necessary precautions since the start of the Tour, which included regular testing and rigorous Covid-19 counter measure planning and protocols,” said Ben Calveley, Managing Director for the British & Irish Lions.
“Our priority is to ensure the health and safety of the entire touring party, which is why we quickly isolated the players and staff upon receiving the news of the positive result.
“Everyone has subsequently been lateral flow and PCR tested. The Medical Advisory Group awaits the results of the PCR testing in order to make a decision on tonight’s game.
“The five individuals affected will be monitored closely during isolation and receive the best possible medical attention as we await the results of their PCR tests.“Further updates will follow in due course.”
The Springboks also cancelled their second test against Georgia on Wednesday after a Covid outbreak in both camps.