Several factors prevent bacteria from colonizing and infecting our skin. A healthy skin barrier acts as the first line of defense.
The Skin's Natural Defenses
Our skin is surprisingly effective at keeping out harmful bacteria. Several mechanisms contribute to this:
-
Intact Skin Barrier: A healthy epidermis (outer skin layer) acts as a physical barrier, preventing bacteria from entering. Cuts, scrapes, and other breaches in this barrier compromise this defense, increasing the risk of infection. (Preventing bacterial skin infections involves keeping the skin undamaged and clean.)
-
Skin's Low pH: The slightly acidic nature of the skin's surface inhibits the growth of many bacteria.
-
Skin's Normal Microbiota: Beneficial bacteria naturally reside on the skin, competing with harmful bacteria for resources and space, thus preventing the latter's overgrowth. This “good” bacteria, like Staphylococcus epidermidis, even helps protect the skin from water loss and damage. (Commensal skin bacteria assist the innate immune system with eradication of pathogens through production of AMPs and by enhancing the activity... The findings could lead to probiotic treatments to promote skin health during…)
-
Innate Immune System: The skin's immune system includes cells like macrophages and neutrophils, which identify and destroy invading bacteria. (Innate antimicrobial immunity in the skin: A protective barrier against…)
-
Antimicrobial Peptides (AMPs): The skin produces AMPs, which kill bacteria directly.
Maintaining Skin Health to Prevent Bacterial Infections
Practicing good hygiene plays a vital role in preventing bacterial skin infections:
-
Regular Cleaning: Washing the skin regularly with soap and water helps remove bacteria and other pathogens. (Removing some of the bacteria on your skin regularly can prevent unpleasant body odor.)
-
Wound Care: Proper care of cuts and scrapes (cleaning with soap and water and covering with sterile bandages) is essential to prevent infections. (When the skin is cut or scraped, the injury should be washed with soap and water and covered with a sterile bandage. Petrolatum may be applied to open areas to keep the tissue moist and to try to keep bacteria out.)
-
Keeping Skin Moisturized: Dry skin is more susceptible to cracking and bacterial invasion. Maintaining skin hydration can enhance its protective function.
Common Bacteria that Cause Skin Infections
While the skin's defenses are effective, some bacteria can still cause infections. The two most common are:
- Group A Streptococcus (GAS), often called "strep"
- Staphylococcus aureus, commonly called "staph," including the antibiotic-resistant strain methicillin-resistant Staphylococcus aureus (MRSA)
