There lurks a threat far bigger than a mere flu. MRSA. Are you a carrier? Have you ever been tested? Anyone can become a carrier which will lay hidden for years distressing your immune system leaving your easy pickings to any simple virus or bacteria.
What is methicillin resistant Staphylococcus aureus MRSA?
MRSA stands for methicillin resistant Staphylococcus aureus (external - login to view)
) bacteria. This organism is known for causing skin infections, in addition to many other types of infections. There are other designations in the scientific literature for these bacteria according to where the bacteria are acquired by patients, such as community-acquired MRSA (CA-MRSA), and hospital-acquired MRSA or epidemic MRSA (EMRSA).
Although S. aureus
has been causing infections (staph infections) probably as long as the human race has existed, MRSA has a relatively short history. MRSA was first noted in 1961, about two years after the antibiotic (external - login to view) methicillin (external - login to view)
was initially used to treat S. aureus
and other infectious bacteria. The resistance (external - login to view)
to methicillin was due to a penicillin (external - login to view)
-binding protein coded for by a mobile genetic element termed the methicillin resistant gene (mecA). In recent years, the gene has continued to evolve so that many MRSA strains are currently resistant to several different antibiotics. S. aureus
is sometimes termed a "superbug (external - login to view)
" because of its ability to become resistant to several antibiotics. Unfortunately, MRSA can be found worldwide.
What are the signs and symptoms of MRSA infection?
Most MRSA infections are skin infections that produce the following signs and symptoms:
- cellulitis (external - login to view) (infection of the skin or the fat and tissues that lie immediately beneath the skin, usually starting as small red bumps in the skin (external - login to view)),
- boils (external - login to view) (pus-filled infections of hair follicles),
- abscesses (external - login to view) (collections of pus in under the skin),
- sty (external - login to view) (infection of eyelid gland),
- carbuncles (external - login to view) (infections larger than an abscess, usually with several openings to the skin), and
- impetigo (external - login to view) (a skin infection with pus-filled blisters).
One major problem with MRSA is that occasionally the skin infection can spread to almost any other organ in the body. When this happens, more severe symptoms develop. MRSA that spreads to internal organs can become life-threatening. Fever (external - login to view)
, chills, low blood pressure (external - login to view)
, joint pains, severe headaches (external - login to view)
, shortness of breath, and "rash (external - login to view)
over most of the body" are symptoms that need immediate medical attention, especially when associated with skin infections.
How is MRSA infection transmitted?
There are two major ways people become infected with MRSA. The first is physical contact with someone who is either infected or is a carrier (people who are not infected but are colonized with the bacteria on their body) of MRSA. The second way is for people to physically contact MRSA on any objects such as door handles, floors, sinks, or towels that have been touched by an MRSA-infected person or carrier. Normal skin tissue in people usually does not allow MRSA infection to develop; however, if there are cuts, abrasions, or other skin flaws such as psoriasis (external - login to view)
(chronic skin disease with dry patches, redness, and scaly skin), MRSA may proliferate. Many otherwise healthy individuals, especially children and young adults, do not notice small skin imperfections or scrapes and may be lax in taking precautions about skin contacts. This is the likely reason MRSA outbreaks occur in diverse types of people such as school team players (like football players or wrestlers), dormitory residents, and armed-services personnel in constant close contact.
People with higher risk of MRSA infection are those with obvious skin breaks (surgical patients, hospital patients with intravenous lines, burns (external - login to view)
, or skin ulcers) and patients with depressed immune systems (infants, elderly, or HIV (external - login to view)
-infected individuals) or chronic diseases (diabetes (external - login to view)
or cancer (external - login to view)
). Patients with pneumonia (external - login to view)
(lung infection) due to MRSA can transmit MRSA by airborne droplets. Health-care workers as a group are repeatedly exposed to MRSA-positive patients and can have a high rate of infection if precautions are not taken. Health-care workers and patient visitors should use disposable masks, gowns, and gloves when they enter the MRSA-infected patient's room.
How is MRSA diagnosed?
A skin sample (external - login to view)
, pus on the skin, or blood, urine, or biopsy material (tissue sample) is sent to a microbiology lab and cultured for S. aureus
. If S. aureus
is isolated (grown on a Petri plate), the bacteria are then exposed to different antibiotics including methicillin. S. aureus
that grows well when methicillin is in the culture are termed MRSA, and the patient is diagnosed as MRSA-infected. The same procedure is done to determine if someone is an MRSA carrier (screening for a carrier), but sample skin or mucous membrane sites are only swabbed, not biopsied.
In 2008, the U.S. Food and Drug Administration (FDA) approved a rapid blood test that can detect the presence of MRSA genetic material in a blood sample in as little as two hours. The test is also able to determine whether the genetic material is from MRSA or from less dangerous Staph bacteria. The test is not recommended for use in monitoring treatment of MRSA infections and should not be used as the only basis for the diagnosis of a MRSA infection.
How can people prevent MRSA infection?
Not making direct contact with skin, clothing, and any items that come in contact with either MRSA patients or MRSA carriers is the best way to avoid MRSA infection. In many instances, this situation is simply not practical because such infected individuals or carriers are not immediately identifiable. What people can do is to treat and cover (for example, antiseptic cream and a Band-Aid) any skin breaks and use excellent hygiene practices (for example, hand washing with soap after personal contact or toilet use, washing clothes potentially in contact with MRSA patients or carriers, using disposable items when treating MRSA patients). Also available at most stores are antiseptic solutions and wipes to both clean hands and surfaces that may contact MRSA. Pregnant (external - login to view)
individuals need to consult with their doctors if they are infected or are carriers of MRSA. Although MRSA is not transmitted to infants by breastfeeding (external - login to view)
, there are a few reports that infants can be infected by their mothers who have MRSA, but this seems to be an infrequent situation. Some pregnant MRSA carriers have been successfully treated with the antibiotic mupirocin (external - login to view)
Can people die from MRSA infections?
Yes. Currently available statistics from the Kaiser foundation in 2007 (http://www.kaisernetwork.org/daily_reports/rep_index.cfm?DR_ID=45809 (external - login to view)
) indicate that about 1.2 million hospitalized patients have MRSA, and the mortality rate is estimated to be between 4%-10%. In general, CA-MRSA has far less risk as long as the patient does well with treatment and does not require hospitalization.
If MRSA is so resistant to many antibiotics, how is it treated or cured?
Fortunately, most MRSA still can be treated by certain specific antibiotics (for example, vancomycin (external - login to view)
(Vancocin), linezolid (external - login to view)
(Zyvox), and others). For MRSA carriers, mupirocin antibiotic cream can potentially eliminate MRSA from mucous membrane colonization. A good medical practice is to determine, by microbiological techniques done in a lab, which antibiotic(s) can kill the MRSA and use it alone or, more often, in combination with additional antibiotics to treat the infected patient. Since resistance can change quickly, antibiotic treatments may need to change also. Many people think they are "cured" after a few antibiotic doses and stop taking the medicine. This is a bad decision because the MRSA may still be viable in or on the person and reinfect the person. Also, the surviving MRSA may be exposed to low antibiotic doses when the medicine is stopped too soon; this low dose may allow MRSA enough time to become resistant to the medicine. Consequently, MRSA patients (in fact, all patients) treated with appropriate antibiotics should take the entire course of the antibiotic as directed by their doctor. A note of caution is that, in the last few years, there are reports that a new strain of MRSA has evolved that is resistant to vancomycin (VRSA or vancomycin resistant S. aureus
) and other antibiotics. Currently, VRSA is not widespread, but it could be the next "superbug."
Where are other MRSA information sources?
http://www.pnas.org/cgi/content/full/99/11/7687 (external - login to view)
http://www.aafp.org/afp/20061201/tips/18.html (external - login to view)
http://www.kaisernetwork.org/daily_reports/rep_index.cfm?DR_ID=45809 (external - login to view)
Talk to your doctor about being tested.