Coronavirus: Corby and Kettering named 'areas of concern'
BBCAn increase in Covid-19 cases among 20- to 29-year-olds with "active social lives" has led to two towns being added to the government's Covid-19 watchlist.
Corby and Kettering have been named as "areas of concern".
Northampton has been downgraded from an "area of intervention" but remains an "area of enhanced support".
Lucy Wightman, director of Public Health Northamptonshire, said the new cases are largely among those who are "more social, mix more, play sports".
Corby has the fifth highest rate of new cases in English towns and cities with 54 per 100,000 people, according to latest figures.
There have been 39 new cases in Corby and 34 in Kettering in the week up to 30 August.
In all, 145 residents across Northamptonshire have tested positive for the virus in that time.
What is an 'area of concern'?
Public Health England publishes a weekly watch list of local authorities as part of its surveillance report of coronavirus infections.
It has three categories for local councils - area of concern, area of enhanced support and area of intervention.
An area of concern is the lowest level, where local officials take targeted actions to reduce infection numbers.
Following the Greencore outbreak, Northampton was named as an area of intervention - the highest level.
This is where there is a "divergence" between the local measures in place to control the spread of coronavirus and national restrictions across England.
Northampton has now been moved to being an area of enhanced support, described as being at medium or high risk of intervention and having a detailed, nationally agreed plan in place with additional government support.
A local lockdown could be the next step if area of intervention support fails to stem the infection rate. Nowhere in Northamptonshire has had a local lockdown imposed.
The county as a whole has shown a decrease in the rate of positive cases, but levels remain significantly higher than the rate for England as a whole.
Ms Wightman said testing had increased "to one of the highest reporting levels nationally which has enabled us to identify where there are more cases".
She said around half of the cases in Corby link back "to known outbreaks or exposures within workplaces," while in Kettering they "appear more dispersed in the community".
"It does also appear that youngsters in the age range between 20 and 29 are showing an increase in positive cases," she added.
"They tend to be more social, to mix more, play sports and have active social lives.
"We are focusing our efforts towards communicating to these young adults and urging them to protect themselves and their older loved ones and adhere to the guidelines."
In Northampton, the number of cases has fallen significantly from a high of 125.1 per 100,000 people during the week ending 13 August, to 19.5 per 100,000.
The spike in the town was largely caused by a major outbreak at the Greencore sandwich-making factory.
Northampton Borough Council leader Jonathan Nunn said the latest figures were a source of "overwhelming personal relief".
"It is all down to personal behaviour, but complacency remains our biggest enemy," he said.
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