BEIJING, June 19 (Xinhua) -- A Chinese health official said the country must spare no effort to stem the spread of the novel coronavirus, as challenges remain for the medical treatment of COVID-19 patients and epidemiological investigations.

Two provincial-level regions, Beijing and Hebei Province, had reported new local COVID-19 cases for at least five consecutive days by Thursday, Hu Qiangqiang, an official with the National Health Commission, said Friday at a press conference.

The number of severe COVID-19 patients had increased for five straight days as of Thursday, and the count of close contacts under medical observation kept growing, Hu said.