inclusion criteria: * subjects aged from 18-59 years. * signed informed consent forms of the subjects have been obtained. * able and willing to comply with the requirements of the clinical trial protocol and able to complete approximately 8 months of study follow-up. * axillary temperature \< 37.3℃. subjects who fulfill all the required conditions for receiving the candidate vaccine as established by medical history and physical examination and determined by investigators.

inclusion criteria: * subjects aged from 18-59 years. * signed informed consent forms of the subjects have been obtained. * able and willing to comply with the requirements of the clinical trial protocol and able to complete approximately 8 months of study follow-up. * axillary temperature \< 37.3℃. subjects who fulfill all the required conditions for receiving the candidate vaccine as established by medical history and physical examination and determined by investigators.

inclusion criteria: subjects aged from 18-59 years. signed informed consent forms of the subjects have been obtained. able and willing to comply with the requirements of the clinical trial protocol and able to complete approximately 8 months of study follow-up. axillary temperature < 37.3℃. subjects who fulfill all the required conditions for receiving the candidate vaccine as established by medical history and physical examination and determined by investigators.

inclusion criteria: subjects aged from 18-59 years. signed informed consent forms of the subjects have been obtained. able and willing to comply with the requirements of the clinical trial protocol and able to complete approximately 8 months of study follow-up. axillary temperature < 37.3℃. subjects who fulfill all the required conditions for receiving the candidate vaccine as established by medical history and physical examination and determined by investigators.