A mouse study published in the journal Nature recently found that gastrointestinal viruses such as norovirus and rotavirus may be transmitted through saliva. This microbiological research result reveals a previously unknown transmission path of this kind of virus, or indicates that measures to curb the spread of the virus need to adopt better health technology. Gastrointestinal viruses can cause stomach pain, vomiting and diarrhea, and are generally believed to spread through feces and mouth: the virus in the feces of one host will enter another host (such as through contaminated food), replicate in its intestines and excrete in its feces, and continue to replicate in this form. Although the genomic RNA of enterovirus has been detected in the saliva of infected people, such detection results have been considered to be caused by intestinal pollutants. However, scientists at the National Institutes of health have used evidence to show that enteroviruses can infect the salivary glands of mice, and saliva can spread the virus. The research team found that a few days after the mice were vaccinated with norovirus or rotavirus, the mothers of these mice also showed signs of infection. Researchers found genomic RNA from mouse norovirus or rotavirus in the mammary gland of mouse mothers, indicating that the mammary gland may be the site of enterovirus replication, and further suggesting that sucking milk by mouse pups may be a route of transmission. In adult mice, some (but not all) strains of norovirus or rotavirus were found to replicate in salivary glands, and the infection was also caused by injecting the saliva of infected adult mice into mouse pups. The discovery that enteroviruses can replicate in salivary glands has enlightening significance for the study of viral infection and its potential therapy. Through demonstration, the research team showed that mini salivary glands - organoids derived from mouse or human salivary gland cells - could be used to culture mouse and human noroviruses respectively. Compared with the "mini intestinal" organoid system currently used to replicate norovirus for research, this system may be a cheaper and simpler alternative. (outlook new era)