Basic and clinical study of inhalation of inactivated mycobacterium vaccine in the treatment of Novel coronavirus pneumonia (COVID-19)

INTERVENTION: 1:inhalate the mycobacterium vaccae for injection;2:inhalate Physiological saline; CONDITION: Novel Coronavirus Pneumonia (COVID‐19) PRIMARY OUTCOME: viral negative‐transforming time;30‐day cause‐specific mortality;30‐day cause‐adverse events;30‐day all‐cause mortality;co‐infections;Time from severe and critical patients to clinical improvement;Others (liver function, kidney function, myocardial enzyme); INCLUSION CRITERIA: Patients aged >=18 years with novel coronavirus pneumonia who agreed to participate in this trial and signed the informed consent.