Looking back a century or more, bacterial infections were common, scary, and often lethal. The bubonic plague, tuberculosis, leprosy, diphtheria, scarlet fever, syphilis—all levied a heavy toll on humanity. Nowadays there are effective therapies for such diseases, and we unthinkingly rely on medicinal chemicals to cure such maladies.
But what will be the situation a century hence?
There is reason for worry. The pace of drug discovery is not keeping up with the ability of bacteria to develop drug-resistance mechanisms. Solutions to this problem include rethinking the strategies used to develop new drugs and improvements in public-health practices. Both are effective and both are being accomplished in various ways.
But we are also working against ourselves. For the past several decades low-level antibiotics have been widely used to promote growth in farm animals. Estimates are that up to 70% of antibiotic use is for this purpose rather than to treat infections. The practice is effective and makes economic sense. Unfortunately, it is also a very efficient way to promote the emergence of drug-resistant organisms, which may in turn cause untreatable infections.
A new report raises the alarm level (Clinical Infectious Diseases 52:10 [May 15, 2011], 1227–1230). A research team from Northern Arizona University looked for drug-resistant Staph (Staphylococcus aureus) in meat and poultry samples taken from supermarkets in five U.S. cities. Half the samples contained Staph, and virtually all were resistant to at least one antibiotic. Worse, a quarter were multidrug resistant, some even resistant to all known agents.
Why does this matter? Not because people will get Staph infections from the meat they eat (it’s usually cooked, which kills the germs). The problem is that treacherous drug-resistant organisms have been introduced to the ecosystem that would not be there had farm animals not been fed antibiotics.
Is it really worth keeping the cost of meat lower now at the risk of compromising our ability to treat fatal diseases in the future? I think not, and we would be well served to follow the example of Europe and ban the livestock use of antibiotics in the U.S.