Bolton's increasing coronavirus infection rate has been driven in part by outbreaks in care homes and workplaces, experts say.
The town is the only borough in Greater Manchester where the rate of new cases of Covid-19 is on the rise and was pointed out as an area of concern at yesterday's regional press conference (Wednesday).
A new and more transmissible strain of the virus - first discovered in the South East just before Christmas - has now become the most common variant in Bolton, accounting for more than 85 per cent of positive tests.
And, despite weeks of lockdown, the steady fall of infection rates in the population has begun to stall this week.
The borough now has a rate of 288.6 new cases of Covid-19 per 100,000 people, much higher than the rates in neighbouring Wigan (200.8) and Bury (210.5).
The number of new infections is also a long way above the English national average of 188, figures from NHS England show.
One of the factors contributing to these numbers is the persistently high proportion of positive tests among working-age people - from those in their 20s up to people in their 60s - Lynn Donkin, Bolton council's assistant director of public health, explained.
In fact, among those aged above 60, the infection rate is actually falling, albeit slowly.
"It does look like rates have plateaued over the last week," Ms Donkin said.
"When I've looked at what's happening a little more closely there's a little bit of a glimmer of hope in that rates are continuing to come down in the over-60s - I'd like to see that happening more quickly but they are still coming down.
"That's a group we're particularly worried about because of the higher risk of serious illness and death in that age group.
"When we look at all the age groups there's a really important difference in that we've got higher rates in the working age groups and actually that group is accounting for most of our positive results at the moment.
"We've had rates in that age group that have been consistently high, that's not something unique to Bolton it seems to be a feature of a number of Greater Manchester authorities and North West authorities."
Working age people in Bolton now account for three quarters of positive tests in the town.
And, while cases have generally been spread evenly around the borough, the council says there have been some key outbreaks at workplaces and in care homes that have played a part in driving up the overall infection rate.
Public health officials are trying to target some testing towards key workers but increasing the number tests is also likely to add to the rate, Ms Donkin explained
She said: "Within local areas you can see there are differences in the amount of testing that's been done so that can create differences in our ability to detect cases.
"In Bolton at the moment we've got increasing test rates and we're also doing really well with the roll out of our asymptomatic, rapid testing.
"We're targeting that at critical workers, people who are unable to stay at home to do their jobs. We're trying to encourage businesses to engage with that process and get their staff tested twice a week."
She added: "What I'm mindful of is that in Bolton and the North West more broadly, compared to other parts of the country, fewer people here are able to do their jobs from home.
"More people are in the sort of jobs where attendance at work is still allowed or they're not able to do their jobs from home so they have to go in and be physically present. What that means is we may be seeing more mixing and more contact happening compared to the rest of the country."
Another concern for local experts is the rapid spread of the new variant of Covid-19 which has taken hold across the town.
While there is no evidence that this strain is more deadly, its quick transmission speeds are adding to the total numbers of people testing positive for the virus.
It is another reason that experts are urging people to follow the rules closely, Ms Donkin said.
"With the previous variant we might have got away with a little relaxing here and there and forgetting to stick to the rules," she said.
"It's much more difficult now for that to happen, this virus jumps very easily between people, that's the reality."
Bolton council leader David Greenhalgh also said that working-age adults were likely partly behind the town's recent change in infection rates.
He said: “Bolton is not unique in seeing this trend, a similar pattern can be seen across the North West where a higher proportion of people are employed in sectors where they are unable to work from home.
“We are working with employers to promote COVID-safe measures and to introduce asymptomatic testing to alert those who may be passing the virus to their colleagues without realising it.”
