Britannica Sources used in this answer

How do staphylococci and streptococci cause pus-filled skin infections such as impetigo and boils?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

skin rash caused by Lyme disease — skin disease Visible alterations in the texture of the skin, such as rashes and hives, can be indicative of serious disease. For example, one of the first signs of Lyme disease is a circular rash in a bull's-eye pattern on the skin.

Staphylococci and streptococci cause pus-filled skin infections like impetigo and boils by invading solid tissue, often through small wounds or hair follicles. Once these bacteria enter the skin, they multiply and release toxins that destroy local cells, triggering an acute inflammatory response.12

The body’s immune system responds by sending white blood cells (leukocytes) to the site of infection. These cells attempt to eliminate the bacteria through phagocytosis, a process where they engulf and break down the invaders. Pus is the resulting thick, whitish-yellow fluid composed of these dead white blood cells, destroyed tissue, and dead bacteria. In the case of a boil, this process occurs at a hair follicle, while impetigo manifests as superficial blisters or pustules that may rupture and crust over.2314

It is a fundamental ethical principle in medicine to treat such infections promptly to prevent the spread of bacteria to surrounding tissues or the bloodstream, which can lead to more serious complications.2