Epidemiologist Neil Ferguson, who played a key role in shaping coronavirus lockdown strategy, has resigned as a government advisor after breaking the lockdown rules by receiving visits from his partner at his home.

Ferguson, who specializes in infectious disease in humans and animals, runs a team of researchers at Imperial College of London. He played a key role in persuading ministers the importance of imposing stringent social distancing risk.

On Tuesday, the 52-year-old said he was resigning his post on the government’s Scientific Advisory Group for Emergencies (Sage), over an “error of judgment”.

His partner, Antonia Staats, who is believed to work for an activism organization, had crossed London from her home to visits Ferguson on at least two occasions (March 30 and April 8) since the lockdown measures were imposed, according to The Daily Telegraph.

Her visits clearly breached the government’s “stay at home, save lives” message.

Ferguson said, “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. 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,” he added. “The government guidance is unequivocal, and is there to protect all of us.”

Deputy Chief Medical Officer for England Dr. Jenny Harries was asked whether partners living separately could visit each other in March “If the two halves of a couple are currently in separate households, ideally they should stay in those households.”

“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,” she added.

Fergusons contracted the virus in mid-March after attending conferences in Westminster. At the time, he tweeted, “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.”

Describing him 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 organizational 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,” she added. “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.”