After four more patients who recovered from the novel coronavirus volunteered to donate their blood plasma on Wednesday at Changchun Central Blood Bank in Northeast China's Jilin province, the total number of such donors in the provice rose to eight.

On Feb 13, experts said plasma from recovered patients may be effective in treating coronavirus and encouraged recovered patients to donate plasma to save others, especially for those in critical condition.

According to Wang Pengli, deputy Party secretary of Changchun Central Blood Bank, the bank had collected 1,100 milliliters of blood plasma from the first four donors as of Tuesday midnight before undertaking the additional four donations Wednesday afternoon. The donors were in stable condition during the process and the plasma has been carefully tested and preserved .

So far, one patient in critical condition has been treated with the donated plasma at a hospital.