The data was shared by Dr Tony Hill, interim director of public health, at a meeting of the cabinet on Tuesday (November 24).
Dr Hill said Mid Sussex had the highest number of positive cases per 100,000 population (166.2), while Worthing had the lowest (76.9).
The county wide rate was 122.7 cases per 100,000.
This compares to a south east rate of 180.7, while the rate for England stands at 251.5.
Some 20 per cent of positive cases recorded in West Sussex were in the over-60s while the highest rate of infection was in young adults.
Dr Hill told the meeting that, while the latest West Sussex figures showed an increase, the data for the following week, which is not yet complete, suggested a subsequent decrease.
The data also showed that the doubling time – how quickly the virus spreads – had increased to 26.9 days, meaning it is spreading slower than before.
The meeting was told that, as of Thursday (November 26), the local Test and Trace partnership would begin work.
The partnership will see East and West Sussex County Councils working with Public Health England and the seven district and borough councils to track down people who have come into contact with the virus and need to self-isolate.
Essentially, if Public Health England cannot contact a person within 48 hours – usually because the Test and Trace information they submitted was incomplete or inaccurate – then the local partnership will be called on to step in.
Looking at the infection rate in the county’s schools, Lucy Butler, executive director of children, young people & learning, reported a steady increase in positive cases.
In the week ending November 16, 109 were recorded – 68 children and 41 staff – while an increasing number of schools have had to close learning bubbles because of contact with positive cases.
Attendance remains higher than the national average.
As of November 20 it stood at 90.4 per cent, compared to 83.5 per cent for the whole of England.
Nigel Jupp, cabinet member for education, said the county had ‘an exceptionally good record’ for school attendance but would not be complacent.
There were concerns about the amount of pressure placed on council staff during the pandemic – especially those running the community hub.
Deborah Urquhart, cabinet member for environment, said: “Too many of our staff have now for months effectively been doing two jobs covering for colleagues.
“While you can do this for a short period of time you can’t do it for what is now looking like it’s going to be about a year.”
The workload for the community hub team will be added to from Thursday, as they will be responsible for contacting people as part of the Test and Trace programme.
A report to the cabinet recognised the risks of stress and fatigue and said ‘welfare support packages’ were being developed – though no details were given.e