England's contact tracers have only reached about 50% of people who have been in close contact with someone with Covid-19 in an area of Lancashire where new cases are rising.

The figure was revealed by Prof Dominic Harrison, public health director of Blackburn with Darwen Council.

He warned of "exponential growth" of new infections if the system did not become more efficient.

It is not clear why the contacts provided were not able to be reached.

A leaked report, seen by the Independent, suggested that fewer than half of contacts were reached in Oldham, St Helens, Manchester and Rochdale.

Speaking to BBC Radio 4's Broadcasting House programme, Prof Harrison said that Blackburn with Darwen in Lancashire, which he oversees, faces a "rising tide" of infections.

"The key issue here is that 40% of people who are infected by someone with Covid-19 who goes for tests because they have symptoms, will be infected by them before they have those symptoms," he said.

"So, there's a 48 hour window which is critical to get the contacts of the first case contacted, and if we don't get them contacted, and if they don't then get tested and self-isolated, and they then have symptoms, we do risk the spread progressing."

He called for testing and tracing to be carried out at a local rather than national level, and for Public Health England to share more data with local authorities.

Prof Harrison said PHE had only begun sharing data about the postcode areas in which new infections were being registered on 29 June.

"That has made a great difference in three weeks for us in being able to identify what our local outbreak issue is," he said.

"Had we had that data much earlier in this pandemic, I think we could have made progress much more rapidly."

The UK government is to stop publishing daily coronavirus deaths after health secretary Matt Hancock ordered an urgent review into how Public Health England (PHE) calculates the figures.

The health secretary called for a review after researchers claimed the way Covid-19 deaths are reported across England has led to an "over-exaggeration" of the figures due to "statistical flaws".

PHE's calculation of the figures means England’s deaths from coronavirus appear far higher than any other part of the UK, experts behind the study said.

They argue that PHE looks at whether a person has ever tested positive and whether they are still alive at a later date.

The five big changes to England's coronavirus restrictions
This means anyone who has ever tested positive for Covid-19 and then dies is included in the death figures, even if they have died from something else.

The chairman of Jamia Ghosia mosque said they thought there were no restrictions on numbers if hygiene and distancing measures were in place.

The mosque committee said the imam had since "tested positive for Covid 19 and is recovering from the virus".

The mosque advised participants to isolate for seven days or attend a local coronavirus testing station.

Blackburn with Darwen, which has one of the highest infection rates in England, brought in extra restrictions on Tuesday, the day after the funeral.

For the next month, the area's 148,000 residents have been told to observe the new rules in a bid to avoid a Leicester-style lockdown.

This sort of system should be managed by the home office. Only we know the home office don't have the "data"...

Yes except that Ms vacant is accountable to voters. Today there are headlines saying that test and trace breaches GDPR. Talk about stating the obvious!

They seem to think they are invincible , but the pakistanis are the worst carriers .Glad I don"t live around that area .