A Clinical Trial to Evaluate a Recombinant Hepatitis E Vaccine in Healthy Adults

Inclusion Criteria: * Aged between 16 and 65 years with normal intelligence. * Negative in antibody against hepatitis E test. * No plan to go out for a long time within 9 months. * Able to understand the content of informed consent and willing to sign the informed consent * General good health as established by medical history and physical examination. * Able and willing to complete all the secluded study process during the whole study follow-up period. * No history of hepatitis B, hepatitis C and hepatitis E(Patients diagnosed as hepatitis B, hepatitis C and hepatitis E by town or above) * Axillary temperature ≤37.0°C on the day of enrollment Exclusion Criteria: * Woman who is pregnant, breast-feeding or planning to be pregnant during the study period * Allergic history of any vaccination or drugs, or allergic to any ingredient of the Hepatitis E vaccine * History of serious adverse reactions after vaccination, such as allergies, urticaria, breathing difficulties, angioneurotic oedema or abdominal pain * Autoimmune disease or immunodeficiency * Asthma that was unstable and need emergency treatment, hospitalization, oral or intravenous corticosteroid within two years * Type I or II diabetes, not including gestational diabetes * History of thyroidectomy, or need treatment for thyroid disease in the past 12 months * History of serious angioneurotic edema in the past 3 years, or need treatment for it in the past 2 years * Severe hypertension, with the blood pressure still more than 150/100 mmHg after drug maintenance treatment * Abnormal coagulation function (such as coagulation factor deficiency, coagulation disorders, platelet abnormalities) or coagulation disorders diagnosed by the doctor. * Patients who are active or not have a definite cure of malignant tumors, or who may recur in the study period. * Epilepsy, not including alcohol epilepsy in the first 3 years abstinence or simple epilepsy without the need of treatment in the past 3 years * Asplenia or functional asplenia, or asplenia and splenectomy under any circumstances * Guillain Barre Syndrome * Prior administration of immunodepressant, cytotoxic or corticosteroids (not including corticosteroid therapy for allergic rhinitis and acute non concurrent dermatitis )treatment in last 6 months * Prior administration of immune globulin in last 3 months * Prior administration of other research medicines in last 1 month * Prior administration of attenuated vaccine in last 1 month * Prior administration of subunit or inactivated vaccine in last 14 days, such as pneumococcal Vaccine * Current anti-tuberculosis prophylaxis or therapy * Fever (axillary temperature 38.0℃) in 3 days before vaccination or any acute disease, systemic application of antibiotics or antiviral therapy in the past five days * Unable to comply with the study requirements due to the psychological situation, a past or present history of mental disease, two-stage affective psychosis which were not well controlled in the past two years; mental disease need medical treatment, and have suicidal tendency over the past five years * Any condition that in the opinion of the investigators may interfere with the evaluation of study objectives