The former chief medical officer at Fifa was investigating the alleged Russian state doping of footballers when his work was abruptly terminated under the presidency of Gianni Infantino in November last year. Professor Jiri Dvorak, a distinguished doctor and consultant neurologist who worked on Fifa’s medical, anti-doping and injury-prevention programmes for 22 years, complained he was given no notice or explanation when the world game’s ruling body suddenly ended his employment.

The termination of Dvorak and his work, which he combined with chairing the neurology department at the Schulthess clinic in Zurich, was among many departures of Fifa staff after Infantino’s election in February last year to succeed Sepp Blatter. That ousting of people was described as “somewhat brutal” in a highly critical report on Fifa’s governance for the Council of Europe this month by Anne Brasseur, a Luxembourg Democratic party representative.

Dvorak has spoken of his concern that Fifa has discontinued some of the global programmes he initiated as the head of Fifa’s medical assessment and research centre, which pioneered scientific research into health promotion and injury prevention.

Reliable sources have told the Guardian that Dvorak had started to examine the allegations contained in Professor Richard McLaren’s landmark report for the World Anti-Doping Agency in July 2016, which first exposed the vast Russian doping of athletes and systematic cover-ups at the Moscow laboratory.

That report included evidence that 11 footballers were among the athletes doping and alleged Russia’s programme was orchestrated before the 2012 London Olympics and 2014 Winter Olympics in Sochi, under the supervision of the ministry of sport itself.

The minister then was Vitaly Mutko, now a Russian deputy prime minister who remains the president of its FA and chair of the organising committee for the Fifa World Cup in Russia next year.

Dvorak is understood to have contacted McLaren after the first report, to examine the evidence relating to footballers and consider the need for further investigation. He is understood to have written to the Russian FA to request further details, including of its laboratory reports. Dvorak is understood not to have received the information he asked for when Infantino’s regime at Fifa suddenly terminated him.

Following McLaren’s second report last December and further work by the Schmid commission for the International Olympic Committee – which included more allegations of Mutko’s involvement by the principal Russian whistleblower, Dr Grigory Rodchenkov – the IOC barred Russia’s team from the forthcoming Winter Olympics in Pyeongchang and banished Mutko personally from involvement in any Olympic Games. Fifa, however, has taken no action against him or Russia, and continues to rely on the country to host a successful and lucrative 2018 World Cup.

The Guardian revealed this month that the former investigative chairman of Fifa’s ethics committee, the Swiss prosecutor Cornel Borbély, had begun to examine Mutko’s role in the scandal when Borbély’s own tenure was discontinued at the instigation of Infantino at Fifa’s Bahrain congress in May.

The former chair of Fifa’s governance committee, the Portuguese lawyer Miguel Maduro, was also ousted at that congress. He has since said this followed an effort by Infantino to persuade the committee to reverse its decision to bar Mutko from the Fifa council. That ruling was because of Mutko’s position in Russia conflicting with Fifa’s rules that council members must be politically neutral, but Infantino argued that barring Mutko would be damaging to the organisation of the 2018 World Cup.

Brasseur said in her report: “The high number of persons dismissed after the election of Mr Infantino can possibly be explained, at least partially, by the will to remove staff who had been too close to the previous leadership … and maybe also by a certain will of renewal. However, the way in which these changes took place appears somewhat ‘brutal’, as I have heard some of the people define the process.”

None of Borbély, Maduro or Dvorak are understood to have been asked to undertake handover procedures to their successors to ensure their work was not interrupted or delayed.

Dvorak declined to comment on his investigation into Russian doping or his sacking, except to say he was unhappy about his removal, having been given no explanation after 22 years’ work. He said he believed Fifa had a “moral duty” to continue the health-promotion programmes, because of football’s power to communicate. Fifa said as part of a review some “non-core” medical projects, which had “shown a limited impact”, had been terminated.

Asked if the dismissal of Dvorak was connected to his investigations into Russian state doping, or because he was considered close to Blatter, Fifa said in a statement: “As a standard rule Fifa does not comment on individual human-resources matters. As in any other organisation some people leave Fifa and new people come, particularly so during a period of restructuring after the arrival of a new leadership with a new vision. Your speculations around the departure of Prof Dvorak are completely baseless.”

World football’s governing body confirmed it launched an initial investigation into the doping allegations after the publication of the first McLaren report in July 2016, and said that after Dvorak’s departure: “The investigations went on regardless of the presence of Prof Dvorak.”

Fifa insisted it did investigate the evidence contained in McLaren’s first and second reports, and further samples seized from the Moscow laboratory in December 2014 which included 154 footballers, but that “no anti-doping rule violation has been demonstrated for any of them”. A spokesman said it was waiting for further forensic analysis of the seized Moscow samples, using a technique developed by the IOC to determine if bottles have been opened, so possibly tampered with.

Fifa declined to say whether Borbély’s replacement, the Colombian judge María Claudia Rojas, was proceeding with an investigation into Mutko. The organisation has rejected Brasseur’s report, which also questioned Rojas’s suitability as an investigator, as “lacking objectivity”.

Mutko has rejected all allegations of a Russian state doping operation, and did so again at the World Cup draw in Moscow, where Infantino sat alongside him.