Doncaster's director of public health Rupert Suckling has urged residents in the South Yorkshire town to "go above and beyond the Tier 3 restrictions" and not travel unless it is essential.
The borough's latest seven-day case rate was recorded as 530 per 100,000 people. This is the second highest in South Yorkshire and is in the top ten in England
Dr Suckling posted a video message on Doncaster Council's Twitter page:
In the video, Dr Suckling urged Doncaster residents to follow the Tier 3 restrictions, which include; people not meeting with anybody outside their household in any indoor or outdoor setting and restrictions on travel.
"It's clear to me that too many people in Doncaster are still meeting up and not following the guidance to keep our distance, to wear face coverings and to wash our hands.
"If we do not put the fire out now it will continue to flare up and continue burning.
"So I'm asking you all to go above and beyond the Tier 3 restrictions to help keep everyone in the borough safe."
He added: "Please don't travel unless it's essential for you to do so and please stay within Doncaster if you possibly can."
Doncaster has been in Tier 3 since Saturday, along with the rest of South Yorkshire.