What is MRSA?
MRSA stands for Methicillin-Resistant
Staphylococcus Aureus. It is a form of the bacteria, Staphylococcus aureus (Staph aureus), which has become resistant to standard antibiotics –
including the antibiotic methicillin. It is often referred to as a ‘superbug’
due to its ability to resist treatment.
Staph aureus is a common and normally
harmless bacteria, which up to a third of healthy people carry on their skin or
in their nose without even realising it. Many people also carry the resistant
form of the bacteria, MRSA, without experiencing any ill effects. It is only
when these bacteria get inside the body – for example, through a wound or surgical
incision, that they cause infection.
MRSA is no different from normal Staph
aureus in terms of its effects and how it can be spread. The only difference is
that normal Staph aureus infections can be treated much more easily. In people with
normal Staph aureus, standard antibiotics can be used to kill the bacteria.
However, if the bacteria is MRSA, this means that it has developed resistance
to antibiotics and is harder to kill.
Why do bacteria become resistant?
Staph aureus has become increasingly
resistant to a number of different antibiotics over the past 50 years or so. This
is mainly due to the overuse of antibiotics and people not taking their
antibiotic medicine properly.
Bacteria are living organisms that are able
to change and evolve very quickly in order to adapt to their environment. When
a person is given an antibiotic, many of the bacteria are killed straight away.
However, others undergo a mutation (change in their genetic material), which
allows them to adapt and resist the antibiotic.
If a course of antibiotics is not finished,
not all of the bacteria are killed off. This allows those bacteria that have
started to develop resistance to persist, increase their resistance even
further and to multiply.
Not finishing a course of antibiotics
therefore encourages the proliferation of resistant bacteria. Taking
antibiotics when they are not needed – e.g., for a virus rather than a
bacterial infection, also gives more opportunity for resistant strains to
Why is MRSA common in hospitals?
While anyone can carry MRSA, just like
anyone can carry normal Staph aureus, an MRSA infection is more common among
patients in hospitals because they are more likely to have an entry point for
the bacteria to get into their body – e.g., a surgical wound, an iv tube or a
catheter. People in hospital are also more likely to be elderly and to have a
weakened immune system due to their illness/injury – putting them at higher
risk of contracting an infection.
Not only are patients in hospitals at more
risk from MRSA infections than the general population, but hospitals also
provide an ideal environment for the spread of MRSA. This is why there has been
so much focus on ‘dirty hospitals’ and the importance of hygiene in hospitals
over the last few years.
MRSA – like any other bacteria – can easily
be transferred from people’s hands directly to another person, or also
indirectly via surfaces such as door handles, bed rails and linen. MRSA can
survive on objects like these, and without proper cleaning, can be picked up by
another person – be it a doctor or a patient. Hospital staff attend to numerous
different patients throughout the day, giving plenty of opportunity for this
cross-infection from one patient to another.
For this reason, there has been a greater
emphasis over the past few years on the importance of hospital hygiene and adequate
hand hygiene in healthcare workers (i.e., washing hands properly before and
after each patient contact).
What happens if I develop MRSA?
As with ordinary Staph aureus, people can
carry MRSA without it being harmful. This is called being ‘colonised’ with the
bacteria. However, if MRSA bacteria enter the body tissues or bloodstream, e.g.,
through a wound or break in the skin, it can cause infection in almost any part
of the body. These may include minor infections, such as boils or abscesses, or
more serious infections, such as infections of the bone, lungs (pneumonia),
heart (endocarditis) and blood (septicaemia).
If you are suspected as having MRSA, your
doctor will take blood or urine samples, or a swab of the infected tissue to
test for the presence of MRSA bacteria. These tests will also show the doctor
which antibiotics you are resistant to and what can be used to treat you.
You may be moved into a separate, isolated
room in the hospital if you are found to have MRSA, or into a ward with other
people who have the infection. You will still be allowed visitors, as MRSA
rarely presents a danger to healthy people – however, your visitors will need
to ensure they wash their hands thoroughly after seeing you so that they do not
spread the germs to others.
How is MRSA treated?
Staph aureus has become resistant to more
and more different antibiotics over the past few decades, making treatment of
MRSA increasingly difficult.
If you have MRSA, you may need to be
treated with a much higher dose of antibiotics over a much longer period. In
addition, there are two antibiotics – vancomycin and teicoplanin – that most
cases of MRSA have not yet been able to develop resistance to. These medicines
are used as a last resort to treat patients who will not respond to other
antibiotics. They can only be administered by infusion or injection while in
Worryingly, there have recently been a
number of cases in other countries of patients who have developed MRSA that is
also resistant to vancomycin and/or teicoplanin. Scientists are continuing to
investigate new antibiotics that can treat these strains of resistant bacteria.
What is being done about the problem in
Ireland has been found to have one of the
highest prevalence of MRSA in Europe, and has also had one of the greatest
increases in prevalence of the bug over the last few years. The Strategy for
the Control of Antimicrobial Resistance in Ireland (SARI) was set up in
response to the growing problem in 2001.
SARI committees have issued guidelines and
initiated campaigns advising Irish hospitals on how to control the spread of
MRSA and on the importance of good hand hygiene by hospital staff. SARI
committees also work to promote the proper use of antibiotics in the community.
In 2005, the Health Service Executive in
this country began carrying out Hygiene Audits of all Irish hospitals, in order
to check whether hospitals are complying with hygiene standards. The audit
found over 90% of hospitals in Ireland to have inadequate hygiene standards in Nov
2005; however there was significant improvement by the time the second audit
was completed in July 2006.
Under a new Hygiene Services Assessment
Scheme due to begin in 2007, all hospitals will have to undergo a mandatory
self-assessment of hygiene standards every year, followed by an unannounced assessment
by an external assessor. The new scheme aims to take a more comprehensive
approach to testing levels of hygiene than the previous audits and stipulates
that hospitals must have a strategic team co-ordinating hygiene in the hospital
and sufficient resources to ensure rigorous hygiene practices.
What can I do?
If you are prescribed antibiotics:
- Take the medicine exactly as prescribed
- Finish the course
- Do not take medication prescribed for a
- Do not give any antibiotics prescribed for
you to anyone else.
Do not demand or expect to be given a
prescription for antibiotics when you visit your doctor.
If you are visiting someone in hospital,
make sure you wash your hands thoroughly, before and after your visit. Many hospitals
now provide hand hygiene facilities for visitors.