Many people in the room knew that the second disease was oedema. At that time, no, even now they can't actually call it oedema, it can only be referred to as the second disease. Recovery Powder was a homonym, husks of rice husk and bran of wheat bran, it's simply roasted husks mixed with some jaggery, full of expectation that it could aid recovery from the oedema disease.
Upon hearing Cao Hongzhu mention the second disease and Recovery Powder, many people felt a sense of shared suffering. They too had lived through the famine described by Cao Hongzhu, only they were fortunate enough to survive, without turning into a cold corpse among a multitude.