The name Staphylococcus comes from the Greek staphyle, meaning a bunch of grapes, and kokkos, meaning berry, and that is what staph bacteria look like under the microscope, like a bunch of grapes or little round berries.
There are over 30 different types of staphylococci that can infect humans, but most infections are caused by Staphylococcus aureus. These bacteria are commonly found in the nose, as well as on the skin on around 25%-30% of healthy adults and animals. The bacteria can also produce 9 toxins (enterotoxins) and is one of the most common causes of food poisoning. In America, there are almost 250 000 reported cases a year of Staphylococcal food poisoning. These bacteria have a high salt tolerance and the toxins produced are highly stable, heat-resistant and resistant to environmental conditions such as freezing and drying. These bacteria can grow in a wide range of temperatures from 6 degrees Celsius to 46 degrees Celsius and in a pH of 4.2 to 9.3.