NIH scientists discover norovirus and other “stomach viruses” spread through saliva
A class of viruses known to cause severe diarrheal diseases – including the one famous for widespread outbreaks on cruise ships – can grow in the salivary glands and spread through their saliva, scientists at the National Institutes of Health have discovered, according to a news release.
The findings show that a new route of transmission exists for these common viruses, which afflict billions of people each year worldwide and can be deadly.
The transmission of these so-called enteric viruses through saliva suggests that coughing, talking, sneezing, sharing food and utensils, and even kissing all have the potential for spreading the viruses.
The findings, which appear in the journal Nature, could lead to better ways to prevent, diagnose, and treat diseases caused by these viruses, potentially saving lives. The study was led by the National Heart, Lung, and Blood Institute (NHLBI), part of NIH.
Researchers have known for some time that enteric viruses, such as noroviruses and rotaviruses, can spread by eating food or drinking liquids contaminated with fecal matter containing these viruses. Enteric viruses were thought to bypass the salivary gland and target the intestines, exiting later through feces. Although some scientists have suspected there may be another route of transmission, this theory remained largely untested until now.
“This is completely new territory because these viruses were thought to only grow in the intestines,” said senior author Nihal Altan-Bonnet, PhD, Chief of the Laboratory of Host-Pathogen Dynamics at the NHLBI. “Salivary transmission of enteric viruses is another layer of transmission we didn’t know about. It is an entirely new way of thinking about how these viruses can transmit, how they can be diagnosed, and, most importantly, how their spread might be mitigated.”