WUHAN, China—Authorities in Wuhan, the coronavirus pandemic’s original center, revised the local death toll upward by 50%, publicly acknowledging for the first time that they had previously omitted many fatalities, including people who died at home.

The number of deaths in Wuhan attributed to Covid-19, the disease caused by the new coronavirus, increased by 1,290 to 3,869, according to a notice from Wuhan health officials published Friday by China’s state-run Xinhua News Agency.

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