Everyone else, including the CDC, will tell you that norovirus is only present in vomit and diarrhea. However, norovirus is probably present in saliva at least in some people. Here is a research article that checked saliva samples from a family of 6 who all had norovirus. You won't be able to read the entire article unless you buy it. I bought it. The researchers took "oral samples" every morning for 18 days. To obtain the "oral samples", they had the people swish sterile water and spit it out into a sterile container. So, there would likely have been saliva, mouth cells, bacteria, and a few things in that sample besides just saliva. The sample was then analyzed for the presence of norovirus using RT-PCR. The results show that all 6 family members had norovirus present in their saliva for 9-13 days after the vomiting STOPPED from norovirus! 2 of the family members who never had vomiting (only diarrhea) still had norovirus present in their saliva for 10 and 13 days!!! That is really, really upsetting. They also tested saliva samples from people hospitalized for norovirus. In this study, they only found norovirus in the saliva for 2 days after symptoms had stopped and only in 24% of the patients. So, not everyone had norovirus present in their saliva. That hospital study was older and did not use as sensitive detection methods, though. I think more research needs to be done to accurately determine how much norovirus is present in saliva and for how long since this is the ONLY article I could find about it. Hopefully, more research will be done so we can be certain of how scared we need to be. Rotavirus has also been shown to be present in nasal secretions. Therefore, people coughing and spitting when they talk may contribute to the spread of norovirus and rotavirus.
Even if norovirus is present in saliva, staying away from other people who are sick, not putting your hands in your mouth, and thoroughly washing your hands, will protect you from stomach bugs like norovirus most of the time. Keeping some good cleaning products and some good hand sanitizer that kills norovirus on hand is also a good idea. phd.annie at gmail.com
--Annie Pryor, Ph.D.