Following its investigation, the CQC issued a report stating that the provider was failing to meet four essential quality and safety standards.
The report said Serco had failed to employ enough skilled staff to meet the needs of patients and that staff often worked long hours.
A CQC inspection revealed that seven GPs were working for up to 13 hours a day, some from 8am until 7pm and others from 7pm until 8am. The CQC found that the shortage of doctors had resulted in an increased number of complaints to the PCT regarding the service.
The report also found that Serco had failed to protect patients by not training all staff in safeguarding protocols and not making locum GPs aware of local protocols. When the CQC asked staff members about statutory staff training, they were told it was a bit ‘hit and miss’.
In addition to these concerns, Serco also failed to put an effective system in place to monitor the quality of service that patients received, the CQC said.
Responding to the CQC report, managing director of Serco’s clinical services Paul Forden said: ‘We can confirm that we have already implemented actions to ensure that three of the four areas have made progress and we consider that we have achieved the required standards.
‘On the fourth recommendation on training we are 92% compliant today and will fully meet the requirement within the next month.
‘We are confident that we will be able to fully satisfy the CQC that we are meeting all of the standards required when they next visit the service.’
Serco has been given 14 days to provide a report explaining how it will achieve compliance with the CQC's standards.
CQC inspectors will conduct an unannounced revisit of the service at a future date, to check that the required improvements have been made.
GP reported earlier this year that Serco had won a £140m deal to run community health services in Suffolk.