E-mail addresses of 300 contact tracers have been shared accidentally by Serco in what could be a breach of data protection rules.
The government is using the outsourcing firm to help with its tracing strategy aimed at monitoring Covid-19 cases.
The company has been training people to track cases of coronavirus in the UK and has so far recruited 21,000 staff, some of whom are healthcare professionals, according to health secretary Matt Hancock.
Serco made the error when it emailed new trainees to tell them about upcoming training sessions, the BBC reported.
The firm sent an email to trainees to tell them not to contact its help desk to ask for details of the sessions.
However, the staff member who sent the message put trainees' email addresses in the CC section rather than the blind or BCC section.
This meant that every person copied into the email was able to see others’ email addresses.
Serco has since apologised for the blunder and says it is reviewing its privacy processes. The mistake could be a breach of data protection rules and it is understood that one member of staff has reported the incident to the Information Commissioners Office.
A Serco spokesman told the Today Programme: “An email was sent to new recruits who had given us their permission to use their personal email addresses.
“In error, email addresses were visible to other recipients. We have apologised and reviewed our processes to make sure that this does not happen again.”
Last year, the Home Office made a similar error and referred itself to the ICO.
But according to the BBC, Serco has no plans to do this.
The government’s track and trace system has been beset with problems since it first launched on the Isle of Wight at the beginning of May.
The system is run on an app that has been held up by problems over compatibility with some phones, by concerns that it drains phone batteries and hints the government may yet switch systems and start again.
Mr Hancock has carried out a quiet U-turn by recruiting 7,500 medics as part of his 21,000-strong army, after criticism that having only 3,000 was doomed to fail.
However, the majority will still be lowly-paid call handlers, recruited by private firms including Serco, and given as little as one day’s training.
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