Prof Neil Ferguson, the epidemiologist whose modelling helped shape Britain’s coronavirus lockdown strategy, has quit as a government adviser after flouting the rules by receiving visits from his lover at his home. Ferguson runs the group of scientists at Imperial College London whose projections helped persuade ministers of the need to impose stringent physical distancing rules, or risk the NHS being overwhelmed. In a statement on Tuesday, he said he was resigning his post on the government’s Scientific Advisory Group for Emergencies (Sage), over an “error of judgment”. The Daily Telegraph revealed that Antonia Staats had crossed London from her family home to visit him on at least two occasions since lockdown measures were imposed, on 30 March and 8 April. Friends told the newspaper that Staats did not believe their actions to be hypocritical because she considered the households to be one. The visits clearly contravene the government’s “stay at home, save lives” message, which urges people to remain within their family groups and not mix with members of other households. “I accept I made an error of judgment and took the wrong course of action. I have therefore stepped back from my involvement in Sage,” Ferguson said. “I acted in the belief that I was immune, having tested positive for coronavirus, and completely isolated myself for almost two weeks after developing symptoms. “I deeply regret any undermining of the clear messages around the continued need for social distancing to control this devastating epidemic. The government guidance is unequivocal, and is there to protect all of us.” Government advisers have repeatedly warned the public against meetings with members of other households. The deputy chief medical officer for England, Jenny Harries, when asked whether partners living separately could visit each other, said on 24 March: “If the two halves of a couple are currently in separate households, ideally they should stay in those households.” She added: “The alternative might be that, for quite a significant period going forwards, they should test the strength of their relationship and decide whether one wishes to be permanently resident in another household.” Ferguson had become a familiar figure in media interviews during the lockdown, helping to explain the scientific rationale for government decision-making. He contracted the virus in mid-March, apparently after attending meetings in Westminster. “Sigh. Developed a slight dry but persistent cough yesterday and self-isolated even though I felt fine. Then developed high fever at 4am today. There is a lot of Covid-19 in Westminster,” he tweeted on 18 March. Ferguson’s resignation follows questions over the communities secretary, Robert Jenrick, who travelled to one of his homes outside his constituency to spend lockdown there, and drove to his parents’ house to drop off food and medicines. Colleagues have described Ferguson, 51 – whose background is in modelling rather than medicine – as a workaholic. His colleague Christl Donnelly told the Guardian earlier this year: “He works harder than anyone I have ever met. He is simultaneously attending very large numbers of meetings while running the group from an organisational point of view and doing programming himself. Any one of those things could take somebody their full time. “One of his friends said he should slow down – this is a marathon not a sprint. He said he is going to do the marathon at sprint speed. It is not just work ethic – it is also energy. He seems to be able to keep going. He must sleep a bit, but I think not much.” Staats, 38, is believed to work for an activism organisation. Imperial’s modelling claimed that as many as 500,000 deaths could result in the UK from the Covid-19 outbreak if the government failed to implement stringent enough distancing measures, and Ferguson warned recently that lifting lockdown prematurely could cost 100,000 lives. A government spokesman confirmed Ferguson’s resignation but did not comment further. A statement from Imperial College London said Ferguson “continues to focus on his important research”.