In Bassetlaw, the infection rate for the week up to January 22 was 361.0, reflecting 424 new cases recorded in that week.
This is an increase from 235.8 (277 new cases) the week before, meaning the area saw the largest jump out of anywhere in the country.
This comes as infection rates fell in the Mansfield and Ashfield local authority area.
In Mansfield the rate fell from 583.6 ~(638 new cases) in the week to January 15 to 530.6 (580 new cases) in the week to January 22.
And during the same period the rate in Ashfield fell from 520.6 (666 new cases) to 447.2 (572 new cases)
The rate is expressed as the number of new cases per 100,000 people.
Data for the most recent four days (January 23-26) has been excluded as it does not reflect the true number of cases.