It was recently reported that a new superbug - a bacterium particularly resistant to anti-biotics - had killed one patient in a hospital in Scotland and infected 41 others over nine months. However, ESBL is not a superbug, not new and not confined to Scotland.
Extended spectrum beta-lactamases (ESBLs) are enzymes that can be produced by a range of bacteria. The enzymes make the bacteria resistant to certain antibiotics. According to the Public Health Laboratory Service (PHLS), ESBLs were first recognised in Germany in the 1980s and there have been world-wide outbreaks since 1985. There is no mandatory system for monitoring the levels of ESBLs in British hospitals and they can be very hard to detect. Usually the organism Klebsiella (which is just one of many organisms that can produce ESBLs) is tested for its resistance to the antibiotic ceftazidime, since this resistance is caused largely by ESBLs. The level of resistance is then used as an estimate of the general incidence. ESBLs were found in Hairmyres hospital in Killbride because the microbiology department of the hospital was looking for them, not because this specific hospital was especially infected.
Generally the UK has less of a problem with ESBLs than many other countries, and indications are their prevalence has remained stable since the mid-90s. This does not mean hospitals can be complacent. In general antibiotic resistance has been on the increase.
The incidence of the MRSA superbug in UK hospitals was found to be "alarmingly high" - the highest in Europe - by the European Anti-Microbial Resistance Surveillance Team (Earss). MRSA (methicillin-resistant staphylococcus aureus) is a super strong strain of bacterium that is resistant to commonly used antibiotics. The emergence of superbugs is a worldwide phenomenon and according to the Food and Drugs Administration (FDA) in the USA some particularly nasty staphyloccocus aureus strains are even showing resistance to all antibiotics other than vancomycin, a powerful last-resort drug. Staphylococcus is an extremely common bacteria and it is often responsible for infection in open cuts or wounds. Recently glycopeptide-intermediate resistance staphylococcus aureas (GISA) was isolated in an English hospital for the first time.
Catching a resistant strain of bacteria is not necessarily deadly, but they are much harder to treat. This can mean longer stays in hospital (as alternative antibiotics are tried), and delayed recovery. Weaker or older patients are at risk of dying.
The risk to most people remains low - you are very unlikely to catch a resistant bug going about your daily business. Counter-intuitively, hospitals can be ideal breeding grounds. A certain number of hospital-acquired infections are always to be expected - a large number of patients in fairly close proximity are being treated for various conditions which can involve many different illnesses, infections and, of course open wounds. A variety of treatments, including many different types of antibiotics, are also likely to be used. Many patients' immune systems will also be weakened by existing illness.
Overprescribing of antibiotics, especially when they are not needed, is one cause of resistance, the FDA points out. Most cases of colds or flu, for example, are due to viral infections, not bacterial infections, so they won't respond to antibiotics anyway. Patients should also always finish a course of medicine, even if they don't feel ill anymore. The antibiotics kill off the weaker bacteria, but the stronger ones are left over. If you repeat this process a few times, a resistant strain is bred.
The Department of Health states: "Not all hospital-acquired infection is avoidable but a significant proportion is preventable." They are also expensive. A National Audit Office report published two years ago suggested hospital-acquired infections in general were costing the health service £1 bn a year and thousands of deaths.
This is what makes the prevalence of ESBLs and MRSA so scandalous - these organisms thrive in non-hygienic conditions. Basically Britain's hospitals are too dirty. Dr David Livermore, Director of the Antibiotic Resistance Monitoring and Reference Laboratory at the PHLS sums it up: "To prevent further spread of ESBLs and other resistant organisms, basic infection control measures such as washing hands or using alcohol gel rubs between patients, and isolation of affected patients, are essential. To prevent development of resistance the prudent use of antibiotics is essential, along with the continued development of new antibiotics."
