Failings in the NHS Test and Trace system are "hampering" efforts to bring Greater Manchester's coronavirus spikes under control, the mayor has said.
Official figures show just over half of contacts in the region (53%) had been successfully traced up to 4 August.
Mayor Andy Burnham said contact tracing was "critical" to tackling the virus and the "system is not doing that".
The Department of Health and Social Care (DHSC) said it is working closely with local authorities.
There has been widespread criticism of the NHS Test and Trace system with claims that it was "not fast enough"
Mr Burnham said a local approach was required.
"We've got to decide - and decide very quickly - where are we going with this system before we get into the depths of a difficult winter without a vaccine. August is the month to fix this."
The mayor said he wanted a new protocol which would involve the NHS passing on details to local teams and asked for extra resources to support door-to-door tracing.
New lockdown laws banning residents from visiting people's homes and gardens in Greater Manchester, East Lancashire and parts of Yorkshire came into force on 5 August following a spike in cases of Covid-19.
The new measures were introduced four days after vulnerable people were encouraged by the government to stop shielding and told they could no longer claim statutory sick pay.
Mr Burnham said ending shielding support was "inhumane" and was giving "mixed messages".
"It cannot be right at a time when you're asking people to observe extra rules, but you're saying it's okay for people who have been shielding to be going to the shops again."
A DHSC spokeswoman said: "NHS Test and Trace is working, with over 2.6 m people tested and more than 218,000 people prevented from unknowingly spreading the virus.
"Our priority is to curb the spread of this virus and save lives. Local action to tackle outbreaks is crucial, which is why we are working so closely with all local authorities, including Manchester, to provide additional support where needed."