<p>Rotavirus is a virus that causes <a href="https://medlineplus.gov/gastroenteritis.html">gastroenteritis</a>. Symptoms include severe <a href="https://medlineplus.gov/diarrhea.html">diarrhea</a>, vomiting, fever, and dehydration. Almost all children in the U.S. are likely to be infected with rotavirus before their 5th birthday.</p> <p>Infections happen most often in the winter and spring. It is very easy for children with the virus to spread it to other children and sometimes to adults. Once a child gets the virus, it takes about two days to become sick. Vomiting and diarrhea may last from three to eight days.</p> <p>There is no medicine to treat it. To prevent dehydration, have your child drink plenty of liquids. Your health care provider may recommend oral rehydration drinks. Some children need to go to the hospital for IV fluids. Two vaccines against rotavirus infections are available.</p> <p class="">Centers for Disease Control and Prevention</p>