Antibiotic Resistance

Antibiotics have been one of the miracles of modern medicine, and have allowed us to conquer many diseases. However, the more they are used, the more disease organisms can evolve resistance to them and multiply again. As antibiotics lose their efficiency, new ones must be invented to replace them. There is a constant race between microbes and medical researchers to see who can stay ahead. The problem is made worse by the over-prescription of antibiotics where they are not really needed, and by the failure of patients to complete the prescribed treatment because they already feel better, which gives more resistant germs a chance to recover. Antibiotics are even use on healthy livestock to help them grow faster. Much can be done to reduce antibiotic use and thus preserve their effectiveness much longer, but since pharmaceutical companies need to sell more drugs to increase their profits, there is no commercial incentive to reduce overuse. This is an area where the interests of the economy and of society as a whole are in conflict.

Medical authorities are now referring to antibiotic resistance as an "apocalyptic" threat to human health as more super-bugs for tuberculosis and blood infections are emerging that are resistant to all known antibiotics, increasing fourfold over the last decade and escaping from any control. At the same time, most pharmaceutical companies have stopped research into new antibiotics because they are not sufficiently profitable. Public efforts will be needed to increase research and accelerate approval for new drugs (MacKenzie 2013).

Environmental impacts of antibiotics

Heavy use of antibiotics in people and animals, encouraged by commercial pressures, risks causing significant antibiotic contamination of the natural environment and consequent development of resistance in communities of non-disease organisms. Such contamination of microbial communities in septic tanks, sewers, soil, receiving waters and other environmental compartments could create a widespread pool of antibiotic-resistant microbes from which resistance could be transferred back into human and animal disease organisms. The risk from widespread use of antibiotics as growth promoters in livestock is being widely debated (Coghlan, 1996; Bonner, 1997). Antibiotic and other drug resistance is already a major issue in medicine, with significant health and economic impacts, as shown by the resurgence of tuberculosis and malaria, and multiple resistance is easily developed (LeBlanc et al. 1997; MacKenzie 2013). What has not been appreciated is the potential of drugs as environmental pollutants to create new pools of resistance which, given the new evidence of genetic transfers across species, could accelerate the development of resistance in many disease organisms. If new forms of resistance start to come not only from human treatments and hospital settings, but by inter-species transfers from the environment, the growing ineffectiveness of present forms of treatment and a revival of major epidemics is a distinct possibility.

Industrialized countries have the highest antibiotic use, and so could be the first to see the development of environmental pools of resistance. However, with global travel and widespread commerce, drug resistance can be expected to spread steadily to all parts of the world. Developing countries might thus suffer the worst consequences because of the poor state of their health services and their inability to pay for alternatives to cheap antibiotics. Pharmaceutical companies should see that it is in their own interest to minimize drug use and pollution of the environment, since avoiding the spread of resistance will keep their medicines effective longer.

Research is urgently needed into the environmental impacts on natural microbial communities of heavy antibiotic and other drug use in medicine and agriculture/aquaculture. The scenario is plausible, but the risks cannot be estimated because of insufficient understanding. As a precautionary approach, the use of drugs/antibiotics should be reduced to the minimum necessary. In addition, drugs could be developed that break down quickly in the environment; doctors could be assisted, perhaps by expert systems, to chose medicines and to adopt treatment regimes that minimize the risk of creating or spreading resistance; waste treatment facilities that destroy drugs before they contaminate the environment should be installed in hospitals and other settings where drug use is high; and national and international legislation could be considered to prevent or limit the spread of drug resistance.

Bonner, John. 1997. "Hooked on drugs." New Scientist, 18 January 1997, p. 24-27. (also letters commenting on this article in New Scientist, 22 February 1997, p.  51.)

Coghlan, Andy. 1996. "Animal antibiotics 'threaten hospital epidemics'." New Scientist, 27 July 1996, p. 7.

LeBlanc, Donald et al. 1997. Antimicrobial Agents and Chemotherapy 41:1598.

MacKenzie, Debora. 2013. The Bacterial Apocalypse. New Scientist 217(2908):6-7. 16 March 2013.