Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Rotavirus Infections ?
    ### Response:
    Rotavirus is a virus that causes gastroenteritis. Symptoms include severe diarrhea, vomiting, fever, and dehydration. Almost all children in the U.S. are likely to be infected with rotavirus before their 5th birthday.    Infections happen most often in the winter and spring.
    