Overuse of Antibiotics

Animals Resemble Their Guardians More Than We Realize

We humans live with animals and establish very close physical and emotional relationships with them. We are very intimate with our pets: we share our living quarters with them, including beds and sometimes dishes; we kiss them and hug them. We may see a boundary between ourselves and our pets; however for parasites and microorganisms, it is all the same: a dog, a cat, a human, or a cow is just another host to live on.

Bacteria in particular recognize few boundaries. They are the most successful creatures in nature. They have existed from the very beginning of life and they have not changed very much. We can find bacteria everywhere, literally. Bacteria have been found in crevices of deep oil wells where nobody imagined that life could prosper.

Large numbers of bacteria live on our skin and on that of our animals. Some bacteria may be harmful, but most of them are not. In fact, we need bacteria in order to be healthy. In the 1960s, the microbiologist René Dubois noticed piglets growing deformed and unhealthy when they were raised in a sterilized environment. Recently, UK researchers have found that children who are allowed to play with and eat soil are less likely to develop asthma in later years. In other words, bacteria are beneficial and necessary for animals and humans.

Clearly there are bacteria that are also harmful to us and to our animals. Bacteria are still an important cause of disease in poorer regions of the world. However, in rich countries like ours we act based more on fear than on reality, and our obsession with disinfectants and antibiotics is causing more harm than good.

In conventional medical practice it is difficult to resist the use of antibiotics. People expect to be given “a pill” to treat their illness, or their animal’s illness. Many infections are caused by viruses, which antibiotics do not kill. However, the practitioner is under pressure and often does prescribe an antibiotic “just in case.”

With antibiotics we aim to kill all of the bacteria. However, it sometimes happens by chance that some of the bacteria acquire the ability to survive the antibiotic. Those surviving bacteria multiply and colonize the body. With a newer course of antibiotics, susceptible bacteria die but resistant bacteria thrive and acquire even further resistance. Moreover, bacteria are in the habit of interchanging bits of information, carried in the DNA, with other bacterial populations (just as countries exchange technologies with other countries). In this way, resistant bacteria pass on to other bacterial populations the information on how to resist antibiotics. Consequently, bacteria that have not even been exposed to a particular antibiotic may turn out to be resistant to that antibiotic.

Now we have a bacterial population which has ended up being resistant to all of the antibiotics available. These bacteria are called MRSA or Multiple Resistant Staphylococcus Aurous. MRSA used to be confined to hospitals (HP-MRSA), but it is now at large in the general population (CM-MRSA). These bacteria can only be killed with antibiotics which must be given by intravenous injections.

Getting back to our close relationship with animals, MRSA is now found in pets, and it has been found that MRSA can be transmitted from animals to humans. MRSA has caused infections in humans that can only be treated with hospitalization and intravenous antibiotics. This spells potential disaster, since MRSA has the capacity to transfer the information for resistance to other bacteria. More populations of multiple-antibiotic-resistance bacteria will appear faster than our ability to develop newer antibiotics.

Therefore, we must reduce the use of antibiotics. In companion animal medicine, most antibiotics are prescribed for ear problems, skin problems and urinary tract infection. These conditions have underlying causes such as allergies or immune deficiencies, which can be addressed very effectively with alternative therapies.

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