Every yr just like the seasonal flu, the seasonal "stomach bug" goes around.is that caused by norovirus? also why after all this time there's no vax??

Vaccines: Noroviruses & Rotavirus cause many cases of gastroenteritis. RotaTeq® (RV5) & Rotarix® (RV1) are rotavirus vaccines that are administered to infants. Viruses are constantly changing genetically & there are a number of possible viruses that could cause viral gastroenteritis. This makes vaccinating difficult.

Still in phase 1: Hi Check out Vaxart. It's an oral vaccine and the first norovirus vaccine to reach Phase 1 clinical trials (drug testing on human subjects). There's a much longer answer to your question but generally it comes down to if a company wants to spend their resources on it and because of how intensely this sector is monitored and regulated by the federal government.

Contagious virus!: Norovirus is a very contagious virus which you can get from an infected person, contaminated food or water, or by touching contaminated surfaces. Norovirus is the leading cause of foodborne illness in the USA. Japan’s Takeda Pharmaceutical Co. Ltd. has been doing clinical trials for a Norovirus vaccine. I wish you well with your health!