A type of infection is a virus, which is an infectious agent that replicates itself inside the host's cells. Viruses are typically spread through contact with bodily fluids, and can cause a wide range of illnesses. Another type of infection is staph, which is caused by bacteria known as Staphylococcus aureus. Staph infections can be spread through contact with infected surfaces or people, and can cause skin infections, food poisoning, and even toxic shock syndrome.