There is a need for safe, highly infectious Norovirus inocula for use in Norovirus vaccine-challenge studies to assess the efficacy of Norovirus vaccines and examine the immune response among vaccinated and unvaccinated subjects. The purpose of this study is to generate the infection and illness rate and immune response data necessary for the conduct of future investigation of Norovirus vaccine studies.

Inclusion Criteria:

• General good health, without significant medical illness, based on medical history, physical examination, vital signs, and clinical laboratories (CBC, chemistry, and urinalysis) as determined by the investigator in consultation with the research monitor and sponsor
• Available for all planned visits and to spend at least 5 days in confinement
• Confirmed blood type (A or O)
• Demonstrated to be H type-1 antigen secretor positive (by saliva test)
• Body mass index between 17 and 30 at screening
• Female subjects must have a negative pregnancy test and either use contraceptives or be sterile
• Available to return for follow-up visits following discharge from the inpatient unit and deliver stool specimens to the investigator promptly

Exclusion Criteria:

• Presence of significant medical condition
• Donation or use of blood or blood products within 4 weeks prior to challenge
• Diagnosed bleeding disorder or significant bruising or bleeding difficulties that could make blood draws problematic
• Abnormal stool pattern
• Any gastroenteritis within the past 2 weeks
• Occupational hazards, including having daily contact with children under the age of 5, women known to be pregnant, employment in the food service industry, health care workers, etc.

Day 45 ± 3