1. Request medical history and physical examination, and the researchers judged health status of subjects, 2. Aged 18 to 60 years, 3. BMI 18.5-30Kg/m2, 4. Novel Coronavirus (COVID-19) antibodies (IgG, IgM) are negative, 5. Female subjects with childbearing age are not pregnant at the time of admission (negative reaction in urine pregnancy test), 6. Armpit temperature <=37 degree C, 7. The Subjects are able to comply with the study and sign the informed consent voluntarily.

1. Request medical history and physical examination, and the researchers judged health status of subjects, 2. Aged 18 to 60 years, 3. BMI 18.5-30Kg/m2, 4. Novel Coronavirus (COVID-19) antibodies (IgG, IgM) are negative, 5. Female subjects with childbearing age are not pregnant at the time of admission (negative reaction in urine pregnancy test), 6. Armpit temperature <=37 degree C, 7. The Subjects are able to comply with the study and sign the informed consent voluntarily.

1. Request medical history and physical examination, and the researchers judged health status of subjects, 2. Aged 18 to 60 years, 3. BMI 18.5-30Kg/m2, 4. Novel Coronavirus (COVID-19) antibodies (IgG, IgM) are negative, 5. Female subjects with childbearing age are not pregnant at the time of admission (negative reaction in urine pregnancy test), 6. Armpit temperature <=37 degree, 7. The Subjects are able to comply with the study and sign the informed consent voluntarily.

1. Request medical history and physical examination, and the researchers judged health status of subjects, 2. Aged 18 to 60 years, 3. BMI 18.5-30Kg/m2, 4. Novel Coronavirus (COVID-19) antibodies (IgG, IgM) are negative, 5. Female subjects with childbearing age are not pregnant at the time of admission (negative reaction in urine pregnancy test), 6. Armpit temperature <=37 degree, 7. The Subjects are able to comply with the study and sign the informed consent voluntarily.