Encapsulated clusters of noroviruses which can cause stomach flu have been found to be resistant to detergent and ultraviolet disinfection.
Noroviruses are the leading cause of gastroenteritis around the world, with more than 21 million cases annually in the United States. The findings of this study show that there is a need to revise current disinfection, sanitation and hygiene practices which serve to protect against infection with noroviruses.
In 2018, the research team had found that noroviruses can be transmitted to humans in the form of membrane-enclosed packets that contain clusters of viruses. Previously, it was thought that viruses spread via exposure to individual virus particles, but the 2018 study, , showed how membrane-enclosed clusters arrive at a human cell and release a large number of viruses.
For the new study, Drs Danmeng Shuai, Nihal Altan-Bonnet and the study’s first author Mengyang Zhang, a doctoral student co-advised through a GW/NIH Graduate Partnerships Program, examined how such protected virus clusters behave in the environment. They found that the virus clusters could survive disinfection attempts with detergent solutions or even UV light. Water treatment plants use UV light to kill noroviruses and other pathogens, and is being widely used in the COVID pandemic.
“These membrane-cloaked viruses are tricky,” explained study co-author Danmeng Shuai, PhD, associate professor of civil and environmental engineering, George Washington University. “Past research shows they can evade the body’s immune system and that they are highly infectious. Our study shows these membrane enclosed viruses are also able to dodge efforts to kill them with standard disinfectants.”
“We have to consider these viral clusters cloaked in vesicle membranes as unique infectious agents in the public health arena,” added Nihal Altan-Bonnet, PhD, a senior investigator and the head of the Laboratory of Host-Pathogen Dynamics at the National Heart, Lung, and Blood Institute. “When it comes to virulence -; and now with this study, disinfection and sanitation -; the sum is much more than its parts. And these clusters are endowed with properties that are absent from other types of viral particles.”
Future studies are needed to determine whether certain kinds of cleaning solutions or more UV light exposure would degrade the protective membrane and/or kill the viruses inside. Such research would hopefully come up with improved disinfection methods that could be used for cleaning surfaces in the home, in restaurants and in places where norovirus can spread and cause outbreaks, like cruise ships.
“Our study’s findings represent a step towards recommendations for pathogen control in the environment, and public health protection,” Dr Altan-Bonnet said.
Source: News-Medical.Net
Journal information: Zhang, M., et al. (2021) Emerging Pathogenic Unit of Vesicle-Cloaked Murine Norovirus Clusters is Resistant to Environmental Stresses and UV254 Disinfection. Environmental Science and Technology. doi.org/10.1021/acs.est.1c01763.
