Staphylococcus is one of the five most common causes of infections after injury or surgery. It is abbreviated to “S. aureus” or “Staph aureus” in medical literature. S. aureus was discovered in Aberdeen, Scotland in 1880 by the surgeon Sir Alexander Ogston in pus from surgical abscesses.
Transmission of Staphylococcus aureus
S. aureus may occur commonly in the environment. S. aureus is transmitted through air droplets or aerosol. When an infected person coughs or sneezes, he or she releases numerous small droplets of saliva that remain suspended in air. These contain the bacteria and can infect others.
Another common method of transmission is through direct contact such as sex, contaminated objects by the bacteria or by bites from infected persons or animals. Approximately 30% of healthy humans carry S. aureus in their nose, back of the throat and on their skin.
Clinical manifestation of infection
Around one third of healthy individuals carry this bacteria in their noses, pharynx and on their skin. In normal healthy and immunocompentent person, S. aureus colonization of the skin, intestinal tract, or nasopharynx does not lead to any symptoms or disease.
When S. aureus is isolated from an abscess or boil or other skin lesion, it is usually due to its secondary invasion of a wound rather than the primary cause of disease. S. aureus may similarly be isolated from abscesses, breast absecesses or mastitis, dermatitis or skin infections and genital tract infections.
S. aureus is considered the classic opportunist in this way since it takes advantage of broken skin or other entry sites to cause an infection.
What Does S. aureus Cause?
Of the variety of manifestations S. aureus may cause:
1. Minor skin infections, such as pimples, impetigo etc.
2. It may cause boils (furuncles), cellulitis folliculitis, carbuncles
3. It is the cause of scalded skin syndrome and abscesses
4. It may lead to lung infections or pneumonia
5. Brain infections or meningitis
6. Bone infections or osteomyelitis
7. Heart infections or endocarditis
8. Generalized life threatening blood infections or Toxic shock syndrome (TSS), bacteremia and septicaemia.
Staph infections can range from minor skin problems to endocarditis, a life-threatening infection of the inner lining of your heart (endocardium). As a result, signs and symptoms of staph infections vary widely, depending on the location and severity of the infection.
Skin infections caused by staph bacteria include:
Boils. The most common type of staph infection is the boil, a pocket of pus that develops in a hair follicle or oil gland. The skin over the infected area usually becomes red and swollen.
If a boil breaks open, it will probably drain pus. Boils occur most often under the arms or around the groin or buttocks.
Impetigo. This contagious, often painful rash can be caused by staph bacteria. Impetigo usually features large blisters that may ooze fluid and develop a honey-colored crust.
Cellulitis. Cellulitis — an infection of the deeper layers of skin .