Do viruses cause vomiting but never diarrhea?

Viruses can cause both vomiting and diarrhea, but they do not always cause both symptoms. Some viruses, such as norovirus, are more likely to cause vomiting, while others, such as rotavirus, are more likely to cause diarrhea. In some cases, a person may experience both vomiting and diarrhea if they are infected with multiple viruses.