What Is Methicillin-Susceptible Staphylococcus Aureus (MSSA)

What Is Methicillin-Sensitive Staphylococcus Aureus (MSSA)?

Methicillin-sensitive staphylococci are bacteria that develop resistance to the antibiotic methicillin. They are resistant to all antibiotics except penicillins and cephalosporins. There have been several reports of these strains causing infections in hospitals, nursing homes, health care facilities, and other healthcare settings. These strains are commonly referred to as MRSA or MSSA.

These strains can cause infections in both adults and children. Children are at greater risk because they tend to cough up blood more often than adults do. Adults usually get infected through skin contact with contaminated surfaces such as bedding, clothing, equipment, etc., while children typically become infected from direct skin exposure to their mother’s vaginal secretions during childbirth.

The Centers for Disease Control and Prevention (CDC) says that there were approximately 1 million cases of MRSA infection in the United States in 2010. Most of those infections occurred among patients hospitalized for non-infectious conditions such as urinary tract infections, pneumonia, bloodstream infections, and surgical procedures.

How Are These Bacteria Spread?

Bacteria can spread when someone comes into contact with them or touches objects that have been contaminated with them. The most common ways of becoming infected with these bacteria occurs when an infected person sneezes, coughs, or even talks. Bacteria can also spread when someone touches a contaminated object such as a doorknob or a counter top and then touches his or her own eyes, nose, or mouth before washing his or her hands.

Methicillin-damaged skin bacteria usually causes skin infections and some types of blood poisoning. These bacteria often cause skin infections, particularly in children.

What Are The Symptoms Of These Infections?

Some of the most common symptoms of these skin and soft tissue infections are redness, swelling, pain or a wound that will not heal. Also, a skin lump or bump may be felt under the skin. In some cases there may be a fever.

If these bacteria get into the blood stream, they can cause various serious blood conditions such as infections of the inner organs. Some of these bacteria can also damage joints such as the knees and hips.

These bacteria may also cause more serious infections in people who have weakened immune systems. Some of these individuals include:

People with diabetes

Elderly people

Obese people

People who have had an organ transplant

People who have had an HIV infection

People who have received chemotherapy treatment

What Are The Treatment Options?

Most cases of wound infection caused by these bacteria can be successfully treated with a course of the following antibiotics:






However, some strains are resistant to several types of antibiotics and treatment options may include:

Tazobactam with a carbapenem such as imipenem or meropenem

AFourth generation cephalosporin such as ceftriaxone

How Can I Reduce The Risk Of An Infection?

Several steps should be taken to reduce the risk of infection. These include:

Thoroughly wash your hands with soap and water after changing bandages or touching any infected sites. You should do this at least 10 to 15 times a day.

Do not allow mosquitoes to breed around your home. If possible, get rid of any containers that hold water.

Thoroughly wash all fresh fruits and vegetables.

Seek medical help if you develop a fever or if your wounds produce pus or other signs of infection, such as red streaks moving up your arm.

Consult with your doctor before taking any antibiotics, even over-the-counter medications. Antibiotics can interfere with certain medical tests, such as a tuberculin skin test, and with certain medical treatments.

Do not take antibiotics you do not need. Many viral infections, such as colds and the flu, are becoming harder for doctors to treat due to antibiotic resistance. Many of these illnesses are also self-limiting, meaning they will go away without any intervention.

What Is The Outlook?

The outlook for an infection caused by these bacteria depends on the type of infection and whether or not you have received treatment. Most skin infections caused by these bacteria can be successfully treated with antibiotics and do not usually result in death. However, if left untreated, some of these bacteria can cause serious, life-threatening infections.

Sources & references used in this article:

Nosocomial methicillin-resistant and methicillin-susceptible Staphylococcus aureus primary bacteremia: at what costs? by MA Abramson, DJ Sexton – Infection Control and Hospital …, 1999 – researchgate.net

Vital signs: epidemiology and recent trends in methicillin-resistant and in methicillin-susceptible Staphylococcus aureus bloodstream infections—United … by …, J Nadle, MA Kainer, G Dumyati, S Petit… – … and Mortality Weekly …, 2019 – ncbi.nlm.nih.gov

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Epidemic methicillin-susceptible Staphylococcus aureus lineages are the main cause of infections at an Iranian university hospital by SA Havaei, S Vidovic, N Tahmineh… – Journal of clinical …, 2011 – Am Soc Microbiol

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