Frequently asked questions

Frequently Asked Questions About Infections

Staphlococcus Aureus

What is Staphylococcus Aureus?

Staphylococcus aureus (pronounced staf-ill-o-kok-us or-ee-us), or “staph aureus” for short, is a common bacteria that can cause a wide variety of infections in people, both in community and hospital settings.

Where is Staph aureus found?

Staph aureus is commonly carried on the skin and in the nose of humans, where it mostly causes no harm (this is termed as carriage or colonisation by the bacteria). It has been documented that 30% of people continuously carry Staph aureus in their noses, while many other people carry the bacteria, without any ill effects from time to time.

What infections are associated with Staph aureus?

Staph aureus infections can be localised (confined to one part of the body) or generalised (spread to many parts of the body). Most Staph aureus infections are relatively minor and do not cause a person to become very ill (for example, a boil or an infected cut in the skin). Staph aureus can cause more severe infections that may require treatment in hospital, but these are relatively rare.

Examples of infections caused by Staph aureus include:

  • Infected skin wounds or cuts
  • Boils
  • Impetigo
  • Cellulitis (a type of skin infection)
  • Urinary tract infection (“cystitis”)
  • Sinus infections
  • Pneumonia
  • Bone and joint infections
  • Bacteraemia (also known as bloodstream infection or blood poisoning”)

Some types of Staph aureus can produce toxins (a chemical produced by bacteria that can cause illness). The toxins can cause:

  • Food poisoning
  • Staphylococcal scalded skin syndrome (also known as Ritter’s disease Lyell’s syndrome or toxic epidermal necrosis)
  • Toxic shock syndrome

Please note: Staph aureus is not exclusively the cause of all of the above infections or diseases. Many of the above infections can be caused by other bacteria.

Methicillin Resistant Staphlococcus Aureus (MRSA)

What is MRSA?

MRSA stands for Methicillin Resistant Staphylococcus Aureus. MRSA is a subgroup of Staph aureus that is resistant to a range of antibiotics, including penicillin antibiotics. MRSA first appeared in 1961 soon after the introduction of the antibiotic methicillin (an antibiotic that is no longer in use). Since then MRSA has spread widely in many countries and has been particularly associated with hospitals and other healthcare facilities.

What test is done to diagnose MRSA?

A swab (cotton bud) is taken from both nostrils and both groins. MRSA favours hot moist areas of the body to colonise.

What is the treatment for MRSA and how long is it?

The treatment to eradicate MRSA is a nasal ointment that is inserted into each nostril three times a day for 5 consecutive days. If the MRSA is in the groins a special shower wash/body wash will be prescribed that you will be asked to use once daily for 5 days.

How does a healthcare associated infection affect a patient in hospital?

Even though most people with MRSA carry the germ harmlessly, hospitals take steps to stop the spread of MRSA to other people so that the risk of serious MRSA infections is reduced. The nurses and doctors will wear plastic aprons and gloves when they are caring for you. Patients in hospital who are carrying MRSA are cared for in a single room on their own with an en suite facility. Patients who are carrying MRSA will be given antiseptic body wash and an antiseptic ointment for their nose to try to get rid of the germ. Extra swabs may be taken from the nose and other parts of the body after this treatment to see if MRSA is still present. If a patient has an infection caused by MRSA, an antibiotic will be prescribed. This may be given through a drip.

Can you go home with MRSA?

Yes. Patients with MRSA will be allowed home when medically fit. Most people lose MRSA when they leave hospital and when antibiotics and other treatments are stopped. Relatives including children and friends at home are not at risk from a patient with MRSA who has been discharged from hospital.

Can my family visit me?

MRSA does not harm healthy people, including pregnant women, children and babies. MRSA rarely if ever presents a danger to the general public so friends and family can visit normally. Visitors at Blackrock Clinic will be asked to wear a plastic apron when visiting a patient with MRSA. Visitors will also be asked to clean their hands before and after visiting a person with MRSA, so that they do not spread MRSA to other people. If the family helps to physically care for a person in hospital with MRSA, nursing staff will tell them of any extra precautions that may need to be taken.

What is the difference between colonised and infected MRSA?


When the patient has no sign of clinical infection but is carrying the MRSA micro-organism in their nose or on their skin.


This refers to when the MRSA organism causes clinical infection. 

Are MRSA infections more serious than MSSA infections?

In general MRSA is no more likely to cause an infection than MSSA. Both MRSA and MSSA can cause localised or minor infections and occasionally, generalised or severe infections. Because MRSA is resistant to a wide range of antibiotics this makes antibiotic treatment more difficult. As a result people with severe infections caused by MRSA tend to remain ill for longer. For very severe, life-threatening, infections the risk of death is about two times higher with MRSA than with MSSA.

  • Information on the current levels of MRSA, and other infections in Ireland can be found in the EARSS section of the Health Protection Surveillance Centre (HPSC) website:
  • The 1999 North/South study of MRSA in Ireland is available from the Department of Health and Children’s website:
  • The UK Health Protection Agency has background information on MRSA in the ”Topics A-Z” section of its website:
  • The US Centres for Disease Control (CDC) WEBSITE has information on MRSA (look under “A-Z Index”):

Clostridium Difficile

What is Clostridium Difficile?

Clostridium difficile also known as “C. difficile” and “C diff” is a bacterium (germ) that normally lives in your large intestine (gut/bowel).

A small proportion (less than 1 in 20) of the healthy adult population carry a small amount of Clostridium difficule and don’t experience any problem with it. It is kept in check by the normal “good” bacteria of the intestine.

However, when you take an antibiotic, some of the “good” bacteria die causing the Clostridium difficile bacteria to multiply and you may get an infection in your large intestine.

What are the symptoms of Clostridium difficile?

If you become infected with Clostridium difficile you may get diarrhoea, which has a very unpleasent smell. You may also suffer from stomach cramps, fever, nausea and loss of appetite. Most people only get mildly ill and recover fully from it. However, in certain circumstances you may get seriously ill and develop colitis (inflammation of the bowel). If the colitis is severe it can be life threatening.

What happens if I have Clostridium difficile diarrhoea while I’m in hospital?

In other hospitals you would be moved to a single room with your own private ensuite facilities to prevent the spread of infection through shared use of toilet facilities. However, this does not apply in Blackrock Clinic since every in-patient room is for individual use.

In addition, you must make sure to wash your hands with soap and water after using the toilet and before meals. Staff looking after you will wear aprons and gloves and wash their hands after caring for you.

For more information on Clostridium Difficile click here.


What are Noroviruses?

Noroviruses are one of the most common causes of gastroenteritis (stomach bugs). In the past, noroviruses have also been called “winter vomiting viruses”, “small round structured viruses” or “Norwalk-like viruses”. They belong to a group of viruses called “caliciviruses”.

What are the symptoms of Norovirus infection?

Symptoms include:

  • Nausea (often sudden onset)
  • Vomiting
  • Watery diarrhoea

How does Norovirus spread?

People can become infected with the virus in several ways, including:

  • Contact with an infected person e.g. when caring for someone with norovirus infection
  • Contact with contaminated surfaces or objects and then touching their mouth or muccous membranes
  • In hospitals, healthcare workers and hospital visitors can spread the virus to other patients or contaminate surfaces through hand contact

Consuming contaminated food or water