Clinical Trial: Susceptibility of Human Volunteers With Different Histo-Blood With Different Histo-Blood Group Antigens to Norovirus

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Evaluation of the Susceptibility of Human Volunteers With Different Histo-Blood Group Antigens to Norovirus

Brief Summary:

Objectives: To evaluate the role of human histo-blood group antigens in susceptibility to Norovirus infections.

Description of Study Design: Healthy volunteers with different blood types and low antibody titers to the challenge strain will be challenged orally with a Norovirus in the CCCR inpatient facility. Subjects with resistant (non-secretors) or susceptible (secretors (of either A, B or O blood group)) to the challenge strain will be recruited. The challenge study will be conducted in two groups of twenty, each with approximately ten secretors and ten non-secretors. Three additional subjects per group will serve as alternates in the event that any of the study subjects are unavailable or become ineligible at the time of the inpatient study. Subjects will be monitored daily in the isolation facility for at least five days following this challenge for daily clinical and virological evaluations. Subjects will return to the investigational site for evaluation the day after discharge from the inpatient unit and about 30 days (28-35 days) post challenge.

Study Endpoints: Norovirus infection as assessed by viral shedding, seroconversion and clinical illness assessed by the duration and severity of symptoms

Detailed Summary:

Noroviruses are single-stranded, positive-sense RNA viruses that cause acute gastroenteritis in humans. The prototype Norwalk virus (NV) was identified in a large outbreak of acute gastroenteritis in an elementary school in Norwalk, Ohio, in 1968. Since then, many strains have been described and named by the locations of their first isolation. Genetically, Noroviruses belong to one of four genera within Caliciviridae (CV). Phylogenetic analysis has shown that the Norovirus genus is divided into five genogroups and each genogroup can be further divided into genetic clusters; at least 30 genetic clusters of Noroviruses have been identified.

Noroviruses have been recognized as the most important cause of non-bacterial epidemics of acute gastroenteritis, affecting individuals of all ages, in both developing and developed countries. Such outbreaks usually have high attack rates and have occurred in child care centers, schools, restaurants, summer camps, hospitals, nursing homes, ships (both civilian and military) as well as deployed military troops. The viruses are highly contagious and are able to survive in the environment for extended periods of time. They are spread by contact with environmental surfaces and person-to-person transmission. Noroviruses normally cause moderate-to-severe diarrhea and the disease is often incapacitating and can be fatal in the young and elderly. The most important public health concern is that Noroviruses can cause large water- and food-borne outbreaks, resulting in the virus being classified as a Category B agent.

Noroviruses have also been implicated in several military outbreaks. The "Desert Shield virus" (DSV) isolated in US troops in the 1991 Gulf War was subsequently identified as a Norovirus. Similarly the recently reported "mysterious" attacks of acute gastroenteritis
Sponsor: Children's Hospital Medical Center, Cincinnati

Current Primary Outcome: Measurement of the number of people who develop symptomatic illness after challenge with Norovirus [ Time Frame: 1 month after challenge ]

Original Primary Outcome: Same as current

Current Secondary Outcome:

Original Secondary Outcome:

Information By: Children's Hospital Medical Center, Cincinnati

Dates:
Date Received: October 25, 2010
Date Started: October 2010
Date Completion:
Last Updated: February 9, 2012
Last Verified: February 2012