Hexavalent Recombinant Norovirus vaccine(Hansenula Polymorpha)(Grand Theravac Life Science)

Primary objective: To evaluate the safety and tolerability of different doses of hexavalent recombinant norovirus vaccine (Hansen's yeast) in people aged 6 months and above. Secondary objective: To evaluate the immunogenicity of different doses of hexavalent recombinant norovirus vaccine (Hansen's yeast) in people aged 6 months and above. Exploratory objective: To explore the immune persistence of different doses of hexavalent recombinant norovirus vaccine (Hansen's yeast) in people aged 6 months and above.