Cases in the county have risen by 25 per cent in the seven days up to January 21 with 8,323 recorded. Cases in five to nine year olds doubled during the same week and there was also a big increase in 10 - 14 year olds. People of parental age in their 30s and 40s also have higher case rates than other groups.
Ansaf Azhar, Oxfordshire County Council's director for public health, said: "It was good to see Covid cases in decline during January, but they have now bounced back to some degree and that is particularly marked in very young age groups. Our cases in primary school and early secondary school age children in Oxfordshire are among the highest in the south east of England.
"With Plan B restrictions being eased on January 27, people will naturally want to relax and be less guarded. That's understandable after all we've been through this last two years. However, it's worth people knowing that cases are still at a really high level and factor this into their plans as they go about their daily lives.
"Ventilating indoor spaces, washing hands regularly and all of the other sound advice that has applied throughout the pandemic is still important. For those who have not yet had the booster jab, we would encourage you to come forward as soon as possible if you are eligible.
"We are of course continuing to monitor the statistics on a weekly basis and we will draw people's attention to important trends when they arise. This is certainly one such occasion - with a change in the trajectory of local cases very evident, especially among the young.
"Nationally, the message remains that we should all be cautious and we would certainly reflect that here in Oxfordshire."