As one of the most abundant life forms on Earth, bacteria live virtually everywhere — including on and in humans. Some of these bacteria, such as those that live in your large intestine, actually help keep you healthy.
However, others don’t play nicely with your body and can cause infections and infectious diseases. Staph bacteria rank among the leading culprits for human infections, some of which (but not all) require antibiotic treatment.
What Is a Staph Infection?
Some members of the Staphylococcus family of bacteria live on your skin and sometimes in your nose. The presence of these surface bacteria usually doesn’t constitute an infection, as they cause no harm.
A staph infection occurs only when these bacteria invade the body and cause signs or symptoms. The types of staph infections differ in severity, depending on the site and spread of the bacteria.
The staph species called Staphylococcus aureus (S. aureus) accounts for many of the most serious staph infections. Increasing numbers of S. aureus bacteria are now resistant to the penicillin-like antibiotic called methicillin. These bacteria are known as methicillin-resistant S. aureus, or MRSA.
Superficial Staph Infections
Because staph bacteria normally live on the skin, they commonly invade through breaks in the skin, such as a minor cut or scrape. In most cases, these infections remain superficial and require no antibiotic treatment because your immune system kills the bacteria before they can invade further.
If you’ve ever sustained a small cut that looks a little pink around the edges the next day, you likely had a minor staph infection.
Invasive Staph Infections
But sometimes superficial staph skin infections spread deeper into the soft tissues beneath the skin or invade body organs or tissues, such as the lungs, bones, bladder or bloodstream, among others. These invasive staph infections require antibiotic therapy to clear the bacteria from the body.
Signs and Symptoms of a Staph Infection
Signs of a superficial staph infection can include skin redness, warmth and pus drainage. Keep in mind, however, that none of these are specific to staph, as other bacterial skin infections can cause identical symptoms. Laboratory testing is the only way to definitively establish the presence of a staph infection versus an infection caused by other bacteria.
Similarly, any invasive bacterial infection of the soft tissues, lungs, bloodstream, bones or other body organs cause the same signs and symptoms, regardless of the causative bacteria. Fever typically occurs with any type of invasive bacterial infection, including staph. A few examples of common signs and symptoms of infections possibly caused by staph according to body site include:
- Soft tissue infection (cellulitis): expanding redness or red streaks, progressive pain, swelling and tenderness
- Lungs (pneumonia): cough productive of phlegm and shortness of breath
- Bone (osteomyelitis): localized bone pain, tenderness and warmth over the affected area
- Bladder (cystitis): urinary urgency, frequency and pain with urination
But, again, if you suspect you have a staph infection, it’s best to see your doctor for proper diagnosis and treatment.
Staph Infection Treatment
Your health care provider takes into account several factors in deciding whether your infection requires antimicrobial treatment and, if so, the best types of antibiotics to prescribe.
These factors include:
- Site of the infection
- Severity of the infection
- The health of your immune system
- Whether the causative bacteria is MRSA or another type of staph
Based on these factors, you can expect one of the following courses of treatment.
For superficial abscesses (a walled-off pocket of pus and bacteria) or boils, doctors typically drain the infection. This procedure usually cures the infection without antibiotic treatment.
For more serious/invasive non-MRSA staph infections, health care providers have several types of antibiotics, including:
- Penicillin-like drugs, such as amoxicillin/clavulanate (Augmentin), dicloxacillin, nafcillin or oxacillin
- Cephalosporins, such as cefazolin, cephalexin (Keflex) or ceftriaxone
- Tetracyclines, such as doxycycline (Monodox) or minocycline (Minocin)
Carbapenams, such as
ertapenem (Invanz), imipenem or meropenem (Merrem) Clindamycin Trimethoprim-sulfamethoxazole (Bactrim)
For more serious/invasive MRSA infections, the penicillin-like drugs, cephalosporins and carbapenams are ineffective. However, tetracyclines, clindamycin and trimethoprim/sulfamethoxazole are still potential types of antibiotics for treating a MRSA infection.
Doctors also use another antibiotic called vancomycin (Vancocin), which effectively kills most MRSA. But some S. aureus bacteria are now also resistant to vancomycin. So antibiotic therapy options for infections caused by these bacteria, known as VRSA (vancomycin resistant S. aureus), include:
- Dalbavancin (Dalvance)
- Daptomycin (Cubicin)
- Linezolid (Zyvox)
- Oritavancin (Orbactiv)
- Quinupristin/dalfopristin (Synercid)
- Tedizolid (Sivextro)
- Tigecycline (Tygacil)
Warnings and Precautions
See your doctor right away if you suspect you might have a staph or another type of infection. If your doctor prescribes an antibiotic, take the medicine for the full course your doctor advises.
Don’t stop taking the medicine early, even if you feel completely recovered, because this can promote the growth of antibiotic-resistant bacteria, or so-called “superbugs.”