The World Health Organization has devoted this year's World Health Day (7 April) to the fight against antimicrobial resistance, where bacteria, viruses, and other germs outsmart the drugs used to kill them.
By the 1970s, many scientists believed that germs were all but conquered in the industrialised world, thanks to an arsenal of powerful antibiotics and vaccines and a robust antibiotics pipeline that promised to stay one step ahead of the known ability of bacteria to develop resistance through genetic mutation.
But for several years, it has been clear that the battle has not been won, and the emergence and spread of antimicrobial resistance now poses an urgent threat to global health security, with widespread misuse of anti-infective drugs, globalisation accelerating spread, and the pipeline for new drugs drying up despite the medical need, partly because industrialised country pharmaceutical manufacturers are focusing their attention on more profitable medicines for non-communicable diseases such as cancer, heart disease and diabetes.
Multi-drug resistance an increasing worry
For some infections, such as MRSA, 'extensively drug resistant' tuberculosis, and the latest so-called superbug, NDM-1 - a gene that enables several bacteria to become resistant to the last-resort antibiotics - doctors are exhausting the supply of drugs.
Since it was first identified in India three years ago, several bacteria producing NDM-1 have been detected in scores of countries including the US, Canada, and Australia. There is now growing consensus in the scientific community that multi-drug resistant microbes could render most existing anti-infective medicines highly ineffective within the next few decades. Some experts warn that if the most problematic bacterial strains take hold, the safety of routine surgery, where the ability to combat post-operative infections is crucial, could be threatened.
While antimicrobial resistance cannot be entirely avoided, for many diseases it can be slowed down. Coordinated, global commitment to combating the spread of antimicrobial resistance is urgently needed. The global health community must target the following five priority areas:
1. Rational drug use and regulation
Improper use of antimicrobial drugs - both under-use and over-use, for instance when antibiotics are prescribed for viral infections even though they only work against bacteria - is a major driver of drug resistance. Countries need to introduce standard treatment guidelines for when anti-infective drugs should be used. Simple, rapid, point-of-care diagnostic tests to replace those that require time and costly laboratory support must also be developed to help health workers chose the right type of treatment. Vigilance against counterfeit medicines, which often do not contain enough active ingredient, is also needed.
Systems must be in place to identify antimicrobial resistance and to monitor antibiotic use so that overuse can be detected and stopped.
National campaigns to inform the public about the need to reduce antibiotic use must be expanded and strengthened globally.
3. Research and development
Incentives must be developed to encourage the pharmaceutical industry to conduct antimicrobial drug research and development, and the global health community and pharmaceutical manufacturers must continue to work together to find the best way forward.
4. Infection prevention
Vaccines are major tools for preventing infections, and continued development of vaccines is an important part of any strategy to address antimicrobial resistance. The use of simple, inexpensive and effective measures such as hospital hygiene, hand washing, the use of bed nets to prevent malaria and condoms to prevent sexually transmitted infections must be encouraged.
5. Clean animal husbandry, aquaculture, and agriculture
The level of antibiotic consumption in animals and agriculture is high; antibiotics are used extensively to control diseases of fruit trees, and to promote growth in healthy animals and fish. Residues of these drugs can cause antimicrobial resistance in both animals and humans. Better regulation of antibiotics in plant agriculture and livestock, and examination of current incentive structures, are required.