Around 3.4 million people in England — 6 percent of the population — have contracted coronavirus, with infection rates twice as high in London, a major antibody study found.

A mass survey of more than 100,000 people — which the government says is the biggest of its kind in the world — suggested the extent of the outbreak varied widely between different areas and population groups.

In London, 13 percent of people had antibodies while in the South West of England it was less than 3 percent, according to the research, released by the Department of Health and Imperial College London. People from Black, Asian and other minority ethnic groups, care workers, and people living in larger households were among the most likely to have been infected.