Thursday May 1 2014
Drug resistance is a growing threat
“WHO calls for urgent action to preserve power of antibiotics and make new ones,” The Guardian reports. The World Health Organization (WHO), has published a report highlighting the growing global threat of drug resistance.
Expert opinions on the implications of the WHO report have been informative, such as the quote, on BBC News, from Dr Jennifer Cohn, medical director of Médecins sans Frontières' Access Campaign, who said that this report should be “a wake-up call to governments to introduce incentives for industry to develop new, affordable antibiotics that do not rely [on] patents and high prices and are adapted to the needs of developing countries”.
What is the basis for these current reports?
The WHO has produced a report entitled “Antimicrobial resistance: Global report on surveillance 2014”. This is based on information it was able to obtain on general antimicrobial resistance gathered from 129 of the 194 member states. It is also based on a focused collection of data from 114 member states for nine antibacterial drugs of public health importance which are used in the following seven specific infections when other antibiotics haven’t worked:
- Escherichia coli, (E. coli) which can cause diarrhoea, urinary tract infections and blood stream infections
- Klebsiella pneumonia, which can cause pneumonia, urinary tract infections and blood stream infections
- Staphylococcus aureus, a cause of wound infections and blood stream infections
- Streptococcus pneumonia, a cause of pneumonia, meningitis and otitis (ear infection)
- Nontyphoidal Salmonella, which causes diarrhoea and blood stream infections
- Shigella, a cause of diarrhoea
- Neisseria gonorrhoea, which causes gonorrhoea
What is antimicrobial resistance?
Antimicrobial resistance occurs when a drug is no longer effective against an infection. This can happen with all types of infections, such as bacterial, viral, fungal or parasitic.
When organisms reproduce, some of them will have genetic mutations. These mutations may mean that the organism is weaker in some way, but it may also mean that the mechanism of action of a drug no longer works on it. These organisms will then reproduce with this genetic mutation and so be resistant to the drug.
This is more likely to happen when antimicrobial drugs are not taken for long enough, leaving enough organisms behind that can reproduce and have genetic changes by chance.
Antimicrobial resistance is therefore driven by overuse, inappropriate prescribing and people not taking the medication as prescribed.
One of the commonly known bacteria that has become resistant to most antibiotics in the UK is ‘MRSA' (Methicillin-resistant Staphylococcus aureus) and is often also referred to as a ‘superbug’.
What are the key findings?
WHO reported huge gaps in the global knowledge of microbial resistance – only between 35 and 92 states were able to provide any data on the use of the nine antibiotics for the seven specific infections.
Even if we take the upper limit of 92 states, this is less than half of all WHO member states who were able to provide any useful data.
Using the available data, it found very high rates of resistance to these common bacteria to the drugs in all WHO regions.
National reports of 50% resistance or more to the drugs were found in two to six of the six WHO global regions.
Other key findings of the report include:
- Multi-drug resistance to tuberculosis (TB) is not being adequately reported, which makes it harder to come up with a global strategy to address it.
- A few countries have reported resistance to the first-line malaria drug called artemisinin and there are concerns that this may spread.
- There are increasing levels of resistance to anti-HIV drugs in people just starting treatment. Previously, the virus might become resistant to the drugs after a prolonged period of time, but now these mutated viruses that are resistant have been spread as a primary infection.
- They also found many gaps and inconsistencies in recording any antimicrobial resistance, which means that governments are not able to coordinate measures to tackle the problem.
What are the potential implications?
What used to be considered minor infections can become life threatening if they are resistant to the available antimicrobial drugs.
Similarly, what were previously thought of as routine surgical operations, such as removing the appendix, could become vulnerable to serious complications due to the risk of infection.
WHO highlights that infections with E. coli and Klebsiella pneumoniae are becoming reliant on the “last resort” antibacterial drugs called carbapenems. WHO says this is concerning because, “these antibacterials are more expensive, may not be available in resource-constrained settings, and are also likely to further accelerate development of resistance”.
In response to the WHO report, Public Health England (PHE) (the NHS body responsible for public health) has reported that:
- resistance of Klebsiella pneumoniae to carbapenems has increased in the UK, but the numbers are still small
- for TB, resistance in the UK to first-line drug treatments is seen in less than 8% of cases and resistance to multiple drugs is seen in 1.6% of cases
- there are high levels of gonorrhoea resistance to antibiotics in the UK which is of concern
What has WHO recommended?
There are three main recommendations, all aimed at improving the understanding of the level of the problem so that strategies can be developed to tackle it. These initial recommendations are:
- to develop standard ways to record antibiotic resistance (resistance of bacteria to drugs) in humans and food-producing animals across all countries
- to improve surveillance of antimicrobial resistance (resistance of all types of infections to drugs) and to measure the health and economic impact of resistance
- strengthened collaboration between the antimicrobial resistance surveillance networks
Analysis by NHS Choices. Follow Behind the Headlines on Twitter. Join the Healthy Evidence forum.