Antibacterial wipes are supposed to kill bacteria. However, the Welsh School of Pharmacy has found that MRSA (superbug) survive in many antibacterial wipes – the wipes themselves can then contaminate anything that comes into contact with them.

It is crucial, say the researchers, that the wipes are thrown away after one clean.

Dr. Gareth Williams, a microbiologist at the Welsh School of Pharmacy, says it is more important to focus on the dirt and debris bacteria thrive on, than to kill them instantly wherever they might be. Dr. Williams presented the research findings at the American Society of Microbiology’s Annual Meeting, Boston, USA.

The team found that it is not uncommon for hospital staff to clean more than one surface with the same wipe. Dr. Williams explained that staff would wipe one thing, perhaps a bed rail, and then move on to several other surfaces (with the same wipe). The researchers went back to the laboratory to see how different wipes performed under these conditions. They found that the wipes were good at taking bacteria away from the first surface – but the bacteria did not die quickly. Subsequent cleaning with the same wipe resulted in contamination.

“What is remarkable is that some of these wipes actually have the words ‘kills MRSA’ written on the box. We found that, under the conditions we observed in actual hospitals, this wasn’t the case,” said Dr. Williams. Even if a wipe is advertised as antibacterial, Dr. Williams stresses that a wipe should only be used for one surface clean, and then discarded – it should never be used for further cleaning.

What is MRSA?

MRSA stands for methicillin-resistant Staphylococcus aureus, and is used to describe several strains of the Staphylococcus aureus bacteria which are resistant to a growing number of antibiotics.

Staphylococcus aureus (bacteria group) lives on the surface of our skin and inside the nose. It is generally harmless – most carriers of it are unaware they have it. Experts estimate that 30% of UK adults carry it on their skin and in their nose.

Staphylococcus aureus spreads easily from person-to-person through contact.

Why is everybody worried about MRSA?

If Staphylococcus aureus enters the body through a cut or wound it can cause serious problems.

If a person is healthy his/her immune system will be able to fight off a Staphylococcus aureus infection, and experience mild symptoms, if any at all. On the other hand, people with weakened immune systems can develop serious problems. People who are ill, or have undergone surgery, e.g. heart surgery or a hip replacement, often have weakened immune systems. In more vulnerable people Staphylococcus aureus bacteria can cause boils, abscesses, impetigo, septic wounds, heart-valve problems, and toxic shock syndrome. In extreme cases, the infected patient can die.

A person who is infected with Staphylococcus aureus and has a weakened immune system needs antibiotics to help clear up the infection. The problem with MRSA bacteria strains is that they are resistant to a growing number of commonly used antibiotics that treat Staphylococcus aureus infections.

MRSA has appeared for three reasons

1. The widespread use of antibiotics
2. Genetic selection
3. Our dislike of taking tablets (not completing a course of antibiotic tablets).

Bacteria constantly evolve – their genes are continually changing, adapting. Because of this, some bacteria will have more resistance to some antibiotics than others. Weaker bacteria are easily destroyed with antibiotics. However, the more resistant ones take longer to die – if they are not killed off they survive and multiply. Their offspring will be resistant to the antibiotic and additional genetics changes will mean that some of them will be even more resistant to antibiotic medication.

A combination of genetic change and our dislike of taking tablets has resulted in Staphylococcus aureus strains which are resistant to many current antibiotics.

It is important for a patient to complete his/her course of antibiotics when they are prescribed – to kill off all the bacteria. If we do not complete the course there is a greater chance that the stronger bacteria survive and produce more drug-resistant offspring. If this more resistant offspring infects another person, and that person does not complete his/her course of antibiotics, even more resistant bacteria may result.

Why is MRSA of concern in hospitals?

There are many people in hospitals with weakened immune systems who could become infected with MRSA. Hospital patients who have an intravenous drip or catheter have a ‘wound’ (caused by the drip or catheter) through which the MRSA can enter. People (staff and patients) are in close proximity to each other in hospital – this raises the risk of MRSA infecting patients with weakened immune systems. A wide range of antibiotics are used in hospitals, this gives the Staphylococcus aureus bacteria a varied environment in which it has a chance to survive, change genetically (adapt) and become resistant to all of them (antibiotics).

American Society for Microbiology 108th General Meeting
http://gm.asm.org

Written by Christian Nordqvist