Affixes

Many of these bacteria cause disease in humans and animals. Examples include enterococcus (Greek enteron, intestine), a type which occurs naturally in the intestine but causes disease if introduced elsewhere in the body; staphylococcus (Greek staphulē, a bunch of grapes, from the way the bacteria clump together), a cause of many diseases; streptococcus (Greek streptos, twisted, from the shape of the bacteria), which causes infections such as scarlet fever. All have plurals in ‑i (staphylococci, streptococci) and adjectives in ‑coccal (gonococcal, meningococcal).