Coronavirus cases in South Yorkshire are four times higher than previously reported.
New Covid-19 rates published by Public Health England suggest around 399 people in the area tested positive in the week to June 21.
Previously published figures had shown 100 cases across the area during that time.
Rates of infections varied from 54.7 per 100,000 in Barnsley to 17.4 per 100,000 in Doncaster.
New data released this week shows that South Yorkshire’s four urban centres – Sheffield, Doncaster, Barnsley and Rotherham – are all in the top 10 worst affected areas for coronavirus based on the latest infection rates.
The new figures are based on people being tested both through Pillar 1 (in hospitals) and Pillar 2 (through drive-through test centres and swabs sent by post).
Until today, only Pillar 1 figures have been published at a local level.
The figures show Leicester had the highest rate of cases in the UK, at 140.2 per 100,000 people – around 497 new cases.
The previously released Pillar 1 data had suggested just 33 cases in the city.
With Leicester going back into lockdown this week, local health officials have been pushing for the government to release more broken down data.
Officials in Greater Manchester said they had been asking the Government to release the data for two months, and when they received it found the number of positive Pillar 1 cases was 78 but overall numbers jumped to 465 when combined with the Pillar 2 data.
At his weekly coronavirus press conference, mayor Andy Burnham said: “It represents a significant number of new cases and while the overall numbers are coming down and transmission is reducing, nevertheless there is still a significant amount of Covid-19 circulating within Greater Manchester.
“For the first time we are seeing the true picture.”
The BMA had also urged the Government to share more information.
Dr Chaand Nagpaul, chairman of the BMA Council, said: “The Prime Minister has talked about a ‘whack a mole’ strategy to tackle local outbreaks, but this is no use if the people leading the response on the ground – be they public health teams or local leaders – are not given the most accurate up-to-date data possible.
“This is crucial to allow swift action and to protect lives and the health service, and something that is not happening right now.
“This is all the more important given that the ‘world leading’ test and trace app is not in place, meaning local leaders and teams armed with up-to-date information will be vital in containing spread of outbreaks.”