Opthalmologist Dr Paul Kabasele, 58, who had worked for Moorfields Eye Hospital at its Croydon site for more than a decade, died at King’s College Hospital on April 24.
His death adds to the growing fatality list among the NHS, which has so far seen the loss of more than 100 staff to coronavirus.
A significant proportion have involved ethnic minority workers and ministers have ordered a review to investigate possible reasons.
Dr Kabasele, originally from the Democratic Republic of Congo, had been working up until the time he fell ill at the end of March. He self-isolated but his condition deteriorated.
He graduated from a university in the Democratic Republic of Congo in 1987 and had 25 years of experience in inflammatory eye diseases and retinal surgery.
He frequently returned to his home country and helped organise medical conferences across the world.
The father of six children, aged 19 to 30, lived in Upper Norwood, near Crystal Palace, with his family.
He had been a church pastor for 30 years and was described by his family as a “spiritual man who made a difference everywhere he went”.
Shortly before his death, he recorded a video message warning against religious leaders peddling “miracle cures” within the community, saying: “This is something we need to take seriously.
"You would not see a mechanic if you have a problem with your tooth. This virus is killing and you need to listen to the experts.”
Younger brother Charles Mwambi, a financial adviser, said: “He was a wonderful person who always put others first. He was a selfless hero on the NHS front line.”
He said he had no known underlying health problems and had been fit and well and working when he was struck down by the virus for which he tested positive.
Dr Omer Kabasele Kosongo, his elder brother, said his death “leaves a huge gap” and added that his brother was a “charismatic pastor” who had made several trips to Africa “to conduct much needed charity cataracts surgery”.
David Probert, the chief executive at Moorfields, said: “Through the past decade, he provided an exceptional level of care to his patients.
He was incredibly hardworking, kind, gentle and a joy to work with. He will be sorely missed by many and his death is a huge loss to us all.”