Understanding the dynamics of viral shedding within Norovirus infected subjects

Simran Budhwar from the University of Virginia, worked with Rachel Mercaldo, Brian McKay, and Dr. Andreas Handel to study shedding of Norovirus.

Abstract: Norovirus (NoV) is a common cause of acute gastroenteritis. Symptoms include vomiting and diarrhea, which can lead to complications such as dehydration and also serve to spread viral particles through bodily fluids. While some infections are asymptomatic, infected individuals shed the virus regardless of disease severity, primarily through stool. To understand the dynamics of viral shedding, previous studies measured viral load in healthy human subjects challenged with various doses of the virus. In the present analysis, data from these studies was combined to better describe NoV shedding over time. We calculated key variables such as peak viral titer, time to peak viral titer, and duration of shedding, in addition to estimating total shedding through the area under the curve (AUC) value of each participant’s total shedding time-series curve. On average, patients shed the virus for 22 days, with the peak viral titer appearing on day 5 following challenge. Peak viral titers were 10.551 (log10) genomic equivalence copies per gram of stool, while AUC averaged at 11.58 (log10) genomic equivalence copies per gram stool. Though these are key variables that are necessary to understand viral shedding, future work should focus on exploring the drivers of variation in viral load and shedding, such as symptoms or other patient-specific factors.