ABSTRACT
Human noroviruses (HuNoVs) are the main causative viral agents in epidemic and endemic acute gastroenteritis worldwide. Despite their impact on the global economic and health burden, developing effective control measures to prevent and treat norovirus gastroenteritis remains a difficult problem to solve. One of the major reasons for this problem is the lack of affordable small animal models and a robust and reproducible In Vitro cell culture system for the propagation of this poorly characterized RNA virus. Recently, the development of a 3-dimensional culture system using pluripotent stem cells to mimic the native small intestine has led to the discovery of new strategies for the cultivation of this virus. In this review, we describe a human stem cell-derived intestinal organoid model that led to the development of the currently available HuNoV In Vitroculture systems that support replication of the virus, and provide helpful insights into HuNoV biology and vaccine and therapeutic development.
ABSTRACT
The advent of the global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) necessitates a thorough study of the stability and transmissibility in the environment. We characterized the stability of SARS-CoV-2 in three water matrices: fresh, tap, and seawater. The minimum infective dose of SARS-CoV-2 in Vero cells was confirmed to be 10 3 PFU/mL. The stability of SARS-CoV-2 varied according to the water matrix: infective SARSCoV-2 was undetectable after treatment with fresh water and seawater, but remained detectable for 2 days in tap water, when starting with an initial concentration of 10 4 PFU/mL. When the starting concentration was increased to 10 5 PFU/mL, a similar trend was observed. In addition, viral RNA persisted longer than infectious virus in all water matrices. This study was conducted in stagnant water containing a significantly high titer of virus, thus, human-to-human transmission of SARS-CoV-2 through the actual aquatic environment is expected to be rare.
ABSTRACT
Human noroviruses (HuNoVs) are the main causative viral agents in epidemic and endemic acute gastroenteritis worldwide. Despite their impact on the global economic and health burden, developing effective control measures to prevent and treat norovirus gastroenteritis remains a difficult problem to solve. One of the major reasons for this problem is the lack of affordable small animal models and a robust and reproducible In Vitro cell culture system for the propagation of this poorly characterized RNA virus. Recently, the development of a 3-dimensional culture system using pluripotent stem cells to mimic the native small intestine has led to the discovery of new strategies for the cultivation of this virus. In this review, we describe a human stem cell-derived intestinal organoid model that led to the development of the currently available HuNoV In Vitroculture systems that support replication of the virus, and provide helpful insights into HuNoV biology and vaccine and therapeutic development.