Pet Corner

Enlarge Image Image Gallery Antibiotics can be harmful for pets. Gentle herbs with antibiotic activity include garlic, goldenseal and thyme.

I’ve been on a rant against synthetic antibiotics for several years now, and I haven’t softened my stance one iota. In fact, if anything I’ve become even more adamantly anti-antibiotic, for a host of reasons.

All About Antibiotics

You probably have heard that the use of antibiotics leads to bacterial strains that have adapted to become resistant to the antibiotics. But how big is the problem? Turns out it is HUGE.

By one account in 1946, just a few years after the introduction of penicillin, 14 percent of the strains isolated from sick patients were already resistant. By the end of that decade, the frequency had jumped to 59 percent in the same hospital. Today, almost all species of bacteria have developed resistant strains; many species have strains that are at least 70 to 80 percent resistant to one or more antibiotics; and some bacterial strains are almost 100 percent resistant to nearly all the antibiotics currently available.

Bacteria, with their extremely rapid reproduction rate, are uniquely adapted to use evolution as a survival mechanism. No synthetic antibiotic yet produced has been able to kill 100 percent of the pathogenic bacteria it is meant to kill (without also killing the patient), and so, no matter how “effective” the antibiotic, there will always be a few resistant bugs left over to regenerate a new subspecies of resistant bacteria.

With bacteria, however, the scenario goes beyond simple evolution: Bacteria’s plasmids (mini-chromosomes that carry genetic information) can transfer antibiotic resistance information from one species to another (say from Streptococcus to Staphylococcus), and the plasmid can transfer resistance information to more than one antibiotic at a time. So, if one Streptococcal strain survives an antibiotic insult from several different antibiotics and thereby “learns” how to resist each of these antibiotics, this strain can transfer this multiple-antibiotic resistance “know-how” to its offspring and to other, entirely different, species of bacteria.

In 1942, the total amount of antibiotic available in the entire world amounted to about 32 liters of penicillin. Today, some 20 million pounds of antibiotics are used annually in this country alone.

Much of the total quantity of antibiotics produced in this country (some estimates indicate more than 80 percent of total production) is fed to food animals at sub-therapeutic levels—levels that promote animal growth (and allow for cheaper meat for the consumer), but that allow for a faster production of resistant bacterial strains. Add to this the fact that several million pets are being treated with antibiotics each year, and it is easy to see how resistant strains are being passed on to farmers, pet-owning families and people living nearby.