RATIONAL USE OF ANTIBIOTICS TO PREVENT EMERGENCE OF ANTIBIOTIC RESISTANT BACTERIA

Infectious disease specialists are making a great effort to educate the public, physicians, veterinarians about this topic because of occasional human infections that are now very nearly untreatable with currently available drugs. For example streptococcus pneumoniae, a common cause of pneumonia, bronchitis, ear and sinus infections was universally susceptible to penicillin for 30 years or so into the antibiotic era. Resistant strains appeared in Australia and South Africa 10 - 15 years ago and are now world wide. In the US these highly resistant strains are now about 10% of isolates in the heartland, 20% on the coasts and 30% in Atlanta (Brought over by the 1996 Olympic participants?). South Korea is the most extreme example with 80% resistant strains. All antibiotics were available there without prescription until July 2000. Wide spread use means that the surviving resident germs in the affected population tend to be resistant to the antibiotic. Similarly, mosquitoes and house flies have become resistant to insecticides after long exposure. A counter measure available for streptococcus pneumoniae is Pneumovax, a vaccine formerly recommended to prevent pneumonia in the chronically ill and elderly. It is now recommended for everybody, one shot every 5 years.

Infectious disease specialists have worried about the emergence of antibiotic resistant bacteria almost from the beginning. They like to save the newest drugs for otherwise untreatable infections and to use adequate doses for sufficient duration to eliminate the infection instead of merely suppressing it. Failure to take all of a prescribed course results in a few left over pills insufficient for future treatment but available to take “at the first sign of a cold.” Some antibiotics become toxic when outdated.

Colds are caused by viruses and run their 5 to 10 day course regardless of treatment. Even bronchitis and sinusitis caused by bacteria are not greatly relieved by antibiotics because they are in an environment (a patch of mucous) with very little blood supply to bring the drugs to them. What to take? Pain pills, expectorants, decongestants, Echinacea. An exception: people with chronic lung disease should take antibiotics for all chest colds to retard future lung damage. And long before all their colds become chest colds they should have stopped smoking (this is the red blooded American doctor sounding off).

Diarrhea is a special situation because antibiotics, by killing the normal bacterial residents, can enhance the growth of disease germs if they are resistant to that antibiotic. If you are only inconvenienced by diarrhea, let it happen. If it was caused by food poisoning, you will get rid of the toxin more promptly. If you have a bacterial or viral infection, you will probably recover before a culture could be reported. If you are gravely ill, get a stool culture promptly to avoid delayed effective treatment. The most important treatment may be rehydration. In the underdeveloped world electrolyte solutions make even cholera treatable over the counter. Gatorade is the most available electrolyte solution in the U.S., but it wouldn’t be so dilute if it were intended for diarrhea (sweat is much more dilute than intestinal secretions).

E. Coli 0157 is a new causative agent for diarrhea which probably arose in cattle. It has acquired a dysentery toxin from another germ. Bacteria occasionally share genetic material even with other species of bacteria. Antibiotic resistance can also be transferred by this quasi sexual mechanism. The use of antibiotics in animal husbandry for growth promotion has fostered a great deal of antibiotic resistance. Less than half of antibiotic use in agriculture is for treatment of disease in animals, and animal use is greater than human use. We also share many bacteria with animals.

Ten years ago, Sweden showed the way to the rest of the world by banning antibiotics in agriculture solely for growth promotion of animals. Swedish meat prices have not risen. Some improvement in animal husbandry was required.

Bottom line: tell your doctor that you have shaped up and will not ask for antibiotics that you don’t need, because he is so good at explaining why you don’t need them. He will rise to the challenge.

John Frantz, M.D.

Chairperson Monroe City Council Board of Health

November, 2000