Do anti-bacterial and disinfectant products promote the spread of superbugs?

No. Although this possibility is often discussed, the scientific evidence does not suggest this is actually happening, despite many decades of use, nor that’s it’s likely to happen.

‘Superbugs’ is just a popular term for new strains of bacteria such as MRSA that are becoming more resistant to some antibiotic medicines, such as penicillin. Antibiotics shouldn’t be confused with anti-bacterial cleaning products or their ingredients – they are totally different. There is no sign at all that bacteria are becoming more resistant to these. Anti-bacterial cleaning products, disinfectants and antiseptics kill superbugs just as easily as ordinary bugs.

The spread of antibiotic-resistant ‘superbugs’ is a serious problem, because when someone becomes infected the doses of many antibiotics that it’s safe to give them no longer clear up the infection. Experts agree the reason for the spread of superbugs is the overuse and abuse of antibiotics, and it’s very important that all of us now use precious antibiotics more selectively and wisely.

Halting the evolution and spread of superbugs like MRSA is a huge challenge. Health authorities recognise that good hygiene to prevent people developing infections in the first place is now more important than ever. Effective antibacterial products, disinfectants and antiseptics that we can use to stop germs spreading, including superbugs, are now even more valuable as part of a properly targeted hygiene approach.

How could antibacterial ingredients affect resistance to antibiotics?

The idea that some antibacterial ingredients used in cleaning products might encourage bacteria that are resistant to antibiotics is based on scientific theory and laboratory studies. But this hasn’t been seen in the real world despite decades of use.

It’s known that bacteria can use the same mechanism to reduce their sensitivity to a wide range of substances. And you can ‘train’ bacteria to tolerate higher and higher doses by exposing them to low doses that are insufficient to kill them. But take away the special ‘training’ conditions and the common, non-resistant strains take over again.

For example, one of these mechanisms works via little ‘pumps’ in the walls of the bacterial cells that allow them to spit out things they don’t like, as it were. These pumps can be ‘switched on’ both by certain antibiotics and by certain anti-bacterial ingredients – but they can also be switched on by dozens of common substances as well, such as garlic, mustard, chilli and various other household products.

Because of these theoretical possibilities, the situation should be carefully monitored, and various UKCPI member companies are engaged in developing scientific understanding of resistance mechanisms. For some ingredients it’s most unlikely that bacteria could develop tolerance because they take bacteria apart, rather than interfering with their workings, and/or they decompose in the process so there’s nothing for the bug to get used to. Such ingredients include sodium hypochlorite and peroxides (used not only in bleaches but also by the human body to destroy invading bacteria) and alcohol for example.

In some applications, where biocides are used at low concentrations, it is prudent to rotate the biocides used to guard against strains of microbes more resistant to a given biocide becoming established.

Contact the UKCPI on ukcpi@ukcpi.org or call 07843 199397.