This is the second part of a guide to avoiding the MRSA superbug. MRSA is an infection that is more dangerous than similar illnesses because it is resistant to normal treatment. MRSA stands for methicillin-resistant Staphylococcus aureus (SA). SA is a type of bacteria and the fact that it is methicillin-resistant means it cannot be treated with antibiotics such as penicillin.

MRSA is no more infectious than other types of bacteria however, and one in three of us carry on our skin or in our nose. It causes skin infections such as boils, styes and impetigo, but is only really dangerous if it gets into the bloodstream when septicaemia, joint problems and heart and lung infections can result.

What causes MRSA?

When bacteria encounter an antibiotic such as methicillin in the bloodstream, an epic battle commences. Antibiotics are not as ruthless as Rambo however, and on occasion some of the bacteria survive. Bacteria are able to mutate, or change themselves, and in doing so can transform themselves so that they develop a resistance to the antibiotic. These surviving antibiotic-resistant bacteria then multiply quickly before heading off to infect someone else. In this way, some types of SA bacteria have become resistant to many antibiotics, and formed the Superbug MRSA.

Why have antibiotic resistant bacteria increased in recent years?

Part of the reason may be that people do not always finish the full course of antibiotics they have been prescribed. This allows some bacteria to survive and then develop a resistance to the antibiotic. Another problem is that antibiotics are now so widely used, and in some cases overused, that bacteria has been able to develop resistance to a wide range of antibiotics.

How does MRSA spread?

MRSA bacteria usually spreads through person-to-person contact with someone who carries an MRSA infection. It also spreads through contact with sheets, clothes, towels, dressings or other objects that have come across someone with MRSA. MRSA will also survive on objects such as door handles, sinks, floors and cleaning equipment and can be contracted through physical contact with them.

Why does MRSA usually happen in hospitals?

MRSA does not normally infect healthy people. Although people outside hospital can sometimes become infected, most cases involve patients already in hospital. This is because an entry point is required for the bacteria to get into the body. Hospital patients have many ready made entry-points such as surgical wounds, catheters, or intravenous tubes which are like adventure playgrounds for the bacteria.

Who is most at risk from MRSA?

People with a weakened immune system are most at risk from being infected. Typically this includes the elderly, newborn babies, and those with health problems such as diabetes, cancer or HIV/AIDS. Patients who have open wounds, catheters or intravenous drips, burns, cuts, severe skin conditions are also at risk, as are those who have recently had surgery, or take frequent courses of antibiotics. Although MRSA infections usually develop in people being treated in hospital, it is possible for hospital staff or visitors to become infected if they are in one of the higher risk groups.