Fourteen areas recorded a rate of new coronavirus cases above 1000 in a week and could be the first to be hit with even tougher restrictions.
The government has so far held back from introducing a Tier 5, which could see schools and universities shut. But many areas in Tier 4 are still seeing soaring cases - and experts have warned London could be first in line if tougher measures are brought in.
London's Epping Forest, in Tier 4, recorded a rate of 1328.9 new cases in the seven days to December 27, the highest rate in England.
This was followed by Thurrock, Essex, with a rate of 1298.6, and then Brentwood, also in Tier 4, with a rate of 1268.5 cases.