Staph Infection and MRSA: Symptoms and Treatment
What Is a Staph Infection?
"Staph" is short for Staphylococcus, a type of bacteria. There are over thirty different types of staph bacteria, but Staphylococcus aureus causes the most infections.1 Types of staph infection include:
- Skin infections like boils (the most common), impetigo, cellulitis, or staphylococcal scalded skin syndrome
- Food poisoning
- Toxic shock syndrome
- Blood poisoning (bacteremia)
- Septic arthritis
Skin infections can happen anywhere on your body, including arms, legs, groin, and face. Like most healthy people, you probably already have staph bacteria on your body, in your nose, or in your throat.1 And most of the time, the bacteria don't cause any problems, or if they do, it's usually a minor skin infection. But, sometimes, the bacteria can cause big problems, including burrowing deep into your body and invade your bloodstream, urinary tract, lungs, and heart, which can be very dangerous and occasionally prove fatal.
In the past, most serious staph infections occurred in people who were hospitalized or who already had a chronic illness or a weakened immune system. But according to a HealthLine article from 2013, a growing number of healthy people are developing serious staph infections,2 and some of these bacteria are resistant to antibiotics. The growing amount of staph bacteria that do not respond to antibiotics is a big public health concern.
Causes of Infection
Staph bacteria can cause illness in two different ways: (1) through direct infection and (2) through toxins that the bacteria produce.1
A staph infection can take many forms.
- Skin infections develop when staph bacteria enter your body via a cut or abrasion in your skin. Eczema, psoriasis, shaving irritations, and other conditions that make your skin more fragile and sensitive will enhance the risk of infection. This is why it is important not to share razors or towels, especially in environments where the risk of coming into contact with staph is higher (like in locker rooms).
- Food poisoning is caused by eating bacteria-containing foods that are not handled or stored properly.
- Toxic shock syndrome, incidences of which have decreased since the 1980s,3 is linked to the used of super-absorbent tampons, as tampons are a great breeding ground for the bacteria. The tampons can also irritate the vagina, making it possible for bacteria to enter the bloodstream. But, toxic shock syndrome can also affect men and children who can be infected by means other than tampons.
- Septic arthritis is caused when staph bacteria spread to a joint from an infection in another part of the body. Rheumatoid arthritis increases the risk of this kind of infection because arthritis medications suppress the immune system.
- MRSA (short for methicillin-resistant Staphylococcus aureus) is a form of staph infection that emerged in hospitals and is now a growing threat in health care facilities worldwide. In hospitals and nursing homes, MRSA can spread on the hands of health care workers and on many surfaces including bedrails, catheters, cart handles, and even remote controls. The staph bacteria involved are resistant to penicillin-type antibiotics.
- CA-MRSA (community-acquired MRSA) is a term for drug-resistant staph infection acquired outside health facilities. People discharged from hospitals may harbor drug-resistant bacteria in their nostrils, and these bacteria can spread further in the community.
What Puts You at Risk?
Although anyone can get a staph infection, the following groups are more likely to get them:4
- Newborn infants
- Breastfeeding women
- People with chronic conditions
- People with suppressed immune systems
- Intravenous drug users
- People who play contact sports
The following make you especially at risk for contracting MRSA:
- Current or recent stay in a hospital.
- Long-term stay in a care facility.
- Use of invasive devices such as catheters or feeding tubes.
Community-acquired MRSA is MRSA that is not necessarily associated with a hospital stay. Here are some risk factors that make you vulnerable:
- Youth. Children do not have fully-developed immune systems.
- Old age. With age, our immune systems begin to decline, making us more subject to illnesses.
- Contact sports. Skin-to skin-contact, abrasions, and cuts are three ways bacteria can spread.
- Sharing towels or athletic equipment.
- Having a weakened immune system.
- Living in crowded or unsanitary conditions.
Different modes of infection can have different signs and symptoms.
- Boils, abscesses, or furuncles — with these, the affected area may be swollen, red, tender or painful, and have draining or pus
- Cellulitis — a potentially life-threatening infection that can leave the skin inflamed and tender. Its symptoms include a swollen, red area of skin that feels hot. It most often occurs on the lower legs, but it can occur anywhere.5
- Impetigo — this is a rash common in young children and infants. It looks like red sores that pop easily and leave a yellow crust.6 It usually goes away on its own in two to three weeks.
- Scalded-skin syndrome — this is a blistering condition that mainly affects newborns and children under the age of five. It presents as large areas of the body with blisters and redness. Large areas of the skin may peel or fall away.
Signs of each of the above conditions will generally include skin redness, swelling, fever, warmth in the area, and tenderness.
Staph infections of the skin are contagious, so careful hygiene is a must when caring for someone with a staph infection.1
Other Conditions Caused by Staph
Symptoms usually begin as soon as six hours after eating, and can end suddenly. Most people fully recover after a day or two. The most common symptoms of food poisoning are abdominal cramps, nausea, vomiting, and diarrhea.
People with food poisoning are not contagious because you can't transmit the toxins from one person to another.1
Toxic Shock Syndrome
- High fever
- Nausea and vomiting
- Rash that resembles sunburn on the palms of the hands and soles of the feet
- Muscle aches
This most often occurs in menstruating women using tampons.1
Usually the knees are targeted, but other joints such as ankles, hips, wrists, elbows, and shoulders can be affected by the bacteria. The symptoms are swelling and severe pain in the joint, fever, and shaking chills.1
Methicillin-resistant Staphylococcus Aureus (MRSA)
- Starts as a superficial skin issue that resembles a pimple or spider bite
- Quickly turns into a deep, painful abscess
- In surgical wounds, the signs are severe pain, redness, swelling, and sometimes draining pus
- In general, the signs can include fever, sweats, and chills
This is most often contracted by people who have recently spent time in or are spending time in health facilities.
Other symptoms may vary according to which parts of the body were infected, as the bacteria can enter the bloodstream, bones, heart lining, and lungs. Symptoms of MRSA infection in the lungs can also include pneumonia (coughing, shortness of breath, chest pains).
MRSA is contagious and most often spread through direct skin-to-skin contact with someone who is infected, or with something that has touched an infected person's skin.1
Staph Infection From a Bug Bite
Diagnosis and Treatment
For simple skin lesions, doctors can usually diagnose through a physical examination.1 For more serious infections or internal infections, doctors will diagnose by taking a tissue sample or nasal secretion. The sample is sent to a lab to check for bacteria growth and to determine what kind of antibiotics will be effective against it.
For many skin lesions, a topical antibiotic will be effective — possibly even one that can be purchased over-the-counter. Oral antibiotics will need to be prescribed in some cases, and for serious infections, intravenous antibiotics will be used.
Penicillin was once an effective antibiotic treatment against the staph bacteria, but the bacteria evolved quickly. After society had been using penicillin for just a decade, half of staph bacteria became resistant to the antibiotic, and now less than 10% of staph infections will respond to penicillin.7
Today, doctors use newer antibiotics, or a combination of antibiotics, in order to treat staph infections. One of these is vancomycin, which is a much stronger and more toxic antibiotic. Although vancomycin is effective in helping those who suffer severe staph infections, it is likely that the bacteria will evolve once again and become resistant to it. A few cases have already been recorded in which bacteria did not respond to vancomycin.1
You can lower your risk by using common-sense precautions.
- Wash your hands and use hand sanitizer.
- Keep wounds covered and clean.
- Watch the high-risk foods that you eat and avoid any foods that have not been stored and cooked properly.
- Reduce tampon risks by changing frequently (at least every 4-8 hours) or switching usage between tampons and sanitary pads.
- Keep your personal items personal by not sharing towels, sheets, razors, clothing, and athletic equipment.
- Get tested so that you have time to get treated in case you do have a staph infection.
- Be especially careful around people who play contact sports, have spent time in hospitals, or live in crowded areas (like nursing homes or dorm rooms).
Pets With Staph Infection
Yes, believe it or not, your pets can contract staph infections, just like you can.
Watch for excessive scratching, as that is the most common cause of staph infection in pets. Scratching can break the Other causes include fleas, inhalant allergy, food allergy, and flea and tick dips. All of these factors can enhance itching.
Watch for a red area on the skin that has a pimple-like bump in the middle. Sometimes staph infection can resemble ringworm. Most of the time it will appear as a crusty abrasion on your dog's belly. You might also notice that your pet has a fever, loss of appetite, exhibits symptoms of pain, or has pus-filled lesions.8
Your vet can diagnose infection in your dog or cat by making skin cultures or a biopsy, and can treat your pet.
Though the infection itself is not contagious from your pet to you, the bacteria itself can get in to an open wound on your skin and cause a separate infection. Therefore, while treating your pet, be careful of any open wounds or scratches that you might have.9
Disclaimer: Please be aware that the advice in this article should in no way replace that of a licensed physician or veterinarian. Consult your doctor or veterinarian if you think that you or your pet might have a staph infection.
- Stöppler, Melissa Conrad MD. "Staph Infection (Staphylococcus Aureus)" Reviewed May 3, 2015. MedicineNet. Accessed April 28, 2017.
- Calhoun Rice, Sandy. "Are Staph Skin Infections on the Rise?" July 26, 2013. HealthLine. Accessed April 28, 2017.
- Reviewed by Nivin Todd, MD. "Understanding Toxic Shock Syndrome -- the Basics." March 14, 2017. WebMD. Accessed April 28, 2017.
- Mayo Clinic Staff. "Staph Infections." June 11, 2014. Mayo Clinic. Accessed April 28, 2017.
- Mayo Clinic Staff. "Cellulitis." February 11, 2015. Mayo Clinic. Accessed April 28, 2017.
- Martel, Janelle. Medically Reviewed by Debra Sullivan, PhD, MSN, RN, CNE, COI. "Impetigo." January 28, 2016. HealthLine. Accessed April 28, 2017.
- Lowy, Franklin D. "Antimicrobial resistance: the example of Staphylococcus aureus." May 1, 2013. The Journal of Clinical Investigation. Accessed April 28, 2017.
- "Staph Infection in Dogs." (n.d.) PetMD. Accessed April 28, 2017.
- Ward, Ernest DVM. "Staphylococcal Dermatitis and Hypersensitivity in Dogs." December 12, 2008. VCA. Accessed April 28, 2017.