Infectivity of Norovirus in Groundwater-Human Challenge Study

Norwalk virus and related "Norwalk-like viruses" are the most common cause of outbreaks of stomach sickness (nausea, vomiting, diarrhea) in older children and adults in the United States. These viruses are sometimes found in drinking water, ice, shellfish and in other foods. They can be spread easily from contact with water, food, objects or hands that have even small amounts of feces from someone who was sick.

The purpose of this research study is to see how long Norwalk virus can survive in water and still be able to cause sickness. When this is determined the researchers will be able to recommend risk levels for norovirus contaminated waters. Another purpose for this study is to see how a person's body's immune cells respond to Norwalk virus in the body. During this study volunteers will receive a dose of Norwalk virus in water that may make them sick.