A virus is a kind of germ that’s so small even a regular microscope can’t see it. Viruses are the smallest and simplest of all germs, but they are also some of the deadliest. Different viruses cause different diseases. Vaccines can prevent some viruses.
Sexually transmitted infections (STIs) caused by a virus (like Herpes and HIV) can’t be cured, but can be treated to help manage symptoms. STI has replaced the term STD (Sexually Transmitted Disease). In medical science, infection is the term used to talk about a bacteria, virus, parasite or other microbe that has entered the body and begun to multiply. The term disease indicates that signs and symptoms of illness are present. There are many people with STIs who have no symptoms, therefore STI is a more accurate term.