Stuart Hyde, ex-chief constable of Cumbria Police, was put into a medically-induced coma and treated for the viral infection.
Mike Pannett, co-director of the 4 Policing consultancy with Mr Hyde, said he was now out of the coma and talking.
He said his family thanked everyone for the messages of love and support which had helped them all "so much".
Mr Hyde retired in 2013 after being suspended twice from the force, investigated and cleared.

The 41-year-old replaces former Scotland team-mate Graham Alexander, who was dismissed on 30 September.
Pressley was sacked by Coventry City in February after almost two years in charge, following a seven-game winless run that left them in the relegation zone.
He recently rejected the chance to talk to Scottish side Dundee United about their vacant managerial position.
Pressley has been working as a coaching for the Scottish Football Association and had just agreed to look after the Scotland Under-17 team on a one-off basis for a three-match round of qualifiers.
In a recent interview with BBC Radio Scotland, after being linked to the role at Dundee United, Pressley said: "I have built up a very good reputation in England and I have a burning desire to manage at the elite level.
"That's not an arrogance. That's a belief. In order to do that, I think you have to manage in a country like England."
The former Hearts and Rangers centre-back started his coaching career at Falkirk in 2010, leaving the Bairns three years later to take charge of Coventry.
He kept the Sky Blues in League One in his first full season in charge despite serious financial difficulties which resulted in the club being docked 10 points for going into administration.
He was fired the following year with Coventry 21st in the table, in a season when they were beaten at home in the first round of the FA Cup by non-league Worcester City.
Meanwhile, Fleetwood have confirmed that assistant manager Chris Lucketti will remain in his role, while Pressley's former Coventry assistant Neil MacFarlane has joined the coaching staff.

The move ends an embarrassing situation for the Archbishop of Canterbury, Justin Welby, who last year pledged to try to put Wonga out of business by helping credit unions compete with it.
It later emerged that the Church had indirectly staked about Â£75,000 in Wonga through an investment fund.
The archbishop told the BBC he was "absolutely delighted" that the investment had ended.
When details of the link emerged last year, Archbishop Welby had admitted to being "embarrassed" and "irritated".
The Church Commissioners for England, which deals with the Church's investments, said on Thursday it was "pleased to announce" the indirect exposure to Wonga as part of its venture capital portfolio had been removed.
"At no time have the commissioners invested directly in Wonga or in other payday lenders," the commissioners' statement said, adding that the indirect exposure was "considerably less than 0.01% of the value of Wonga".
It said the commissioners believed venture capital to be "a good and useful instrument with significant potential to serve the common good", but that a number of "ethical investment changes" had been made.
These included tightening investment restrictions for direct investments, with new controls on indirect investments due to be announced later in the year.
The statement added: "We no longer have any financial or any other interest in Wonga."
In an interview to be broadcast on this Sunday's Andrew Marr show, Archbishop Welby said: "I have been absolutely clear that I do not believe that the rates of interest charged by these companies are ethical and moral - they are legal but they are not ethical or moral."
As he does not sit on the Church's assets committee, he had no "legal right to intervene", he said, adding: "I can obviously apply pressure, encouragement, and I've tried to do that and I'm absolutely delighted that we are now out of Wonga and have taken no profit from it."
Details of the investment emerged in July 2013 shortly after Archbishop Welby said he had "bluntly" told Wonga boss Errol Damelin "we're not in the business of trying to legislate you out of existence; we're trying to compete you out of existence".
The expansion of credit unions would provide an alternative, he had suggested.
Wonga responded by saying it was "all for better consumer choice".
A former top British police officer is out of a coma after contracting meningitis while working in Abu Dhabi.
[NEXT_CONCEPT]
League One side Fleetwood Town have appointed Steven Pressley as manager.
[NEXT_CONCEPT]
The Church of England has ended its investment in the payday lender Wonga.