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What Doesnt Kill Them Makes Them Stronger

Essay, Research Paper

What Doesn?t Kill Them Makes Them Stronger

Humans live in constant contact with not only plants and animals, but also

with bacteria. Bacteria are everywhere: in water and soil and in the bodies of

humans and other animals. The majority of bacteria don?t have the ability to

cause disease, but that doesn?t mean that they are totally harmless. The

problem arises when disease ? causing bacteria interact, and are frequently in

contact with the commensal, or harmless bacteria. They serve as reservoirs for

resistance genes; collecting them and holding them for future transmission to

other bacteria. As the resistance is transmitted from bacteria to bacteria,

eventually it will be passed to one with disease ? causing potential.

Humans have grown accustomed to always having antibiotics just a prescription

away, and knowing that they will cure their illness. These chemical substances,

which are often natural, kill the bacteria by specifically targeting its

ribosome or replication machinery. ?Virtually all of modern medicine rests on

the efficiency of

antibiotics, due to the fact that they not only cure bacterial infections but

also decrease the infectious disease risk of surgery, chemotherapy and

transplants to a low enough level to make them medically possible. But what

happens when these antibiotics fail to do their job, and there is nothing that

can stop the dangerous bacteria from spreading? This resistance to antibiotics

is becoming an increasing threat to the human population and precautions must be

taken to prevent the problem from getting worse.

In today?s society, bacteria are now more mobile than they ever were

before, which makes it even easier for them to multiply and transmit resistance.

They have grown to evolve naturally so that they are able to survive in the

hostile environments they are often subject to. Bacteria, in every environment

where antibiotics are used, are constantly evolving and exchanging genes that

confer resistance to antibiotics. The bacteria are able to transfer genes to one

another by means of horizontal gene transfer. This process allows bacteria to

become resistant to antibiotics by acquiring DNA from another bacterium that

already has the resistance. When the resistance is attained, that particular

antibiotic no longer is able to

inhibit the growth or kill the bacteria. Once a resistant strain is

developed, all of the offspring of that bacterium will contain the resistance.

Because these organisms then pick up further resistance to other drugs and

continue to pass them on, all it?s going to do it get worse.

This problem of resistant bacteria has been found to be an extremely

dangerous concern in today?s hospitals. They account for three out of every

five hospital ? acquired infections, affecting nearly two million Americans.

Half of all of these two million cases are resistant to at least one antibiotic.

Resistance has proved to be an especially worrisome problem for people with

immune disorders such as AIDS, cancer patients, and also recipients of organ

transplants. It has been found that almost 90% of these patients that get

multiple-drug resistant TB end up dying.

A drug ? resistant form of Salmonella, known as Salmonella Typhimurium has

recently emerged in the United States. This Salmonella subtype has been

associated with severe human illness and even death, due to the fact that it has

numerous antimicrobial resistance. Studies show that the Salmonella Typhimurium

is present in animals both wild

and domesticated, and can be easily transmitted to humans. These same studies

show that eating beef, pork, or poultry products has been associated with

outbreaks of the disease in humans.

As soon as a particular strain of virus becomes resistant to an antibiotic,

doctors must be forced to prescribe alternate medications in order to cure the

bacteria. ? If you had an antibiotic recently, you?re three to nine times

more likely to have a resistant infection that someone who has not had an

antibiotic.? Once the different types of antibiotics have been used, there is

not much else that can be done. Unlike other fields of medicine, antibiotics

have not been a main focus of researchers. We are still commonly using

medications such as penicillin, which have been around for over fifty years, but

what has happened with it is also becoming common. When first put to use,

penicillin got rid of all staph (Staphylococcus aureus) infections. Today in the

U.S., more than 90% of these strains are resistant to penicillin, along with

numerous other bacteria. As the antibiotics become more and more popular and are

overused, it is more likely that viruses will develop resistance to them.

Resistance can develop in less time than you would think. For example, it is

a proven fact that one of the most feared bacterial meningitis actually normally

lives in the throats and nasal passages of 5% to 10% of the people in the U.S.

This bacterium lives harmlessly and only rarely causes outbreaks or illness to

the carrier of it. In 1995 there was an outbreak of the disease in a middle

school in Seattle, Washington. In order to try to stop the spread of the

disease, doctors prescribed the antibiotic rifampin to all of the students in

the school. They succeeded and there were no further outbreaks, but they may

have caused an even larger problem because just three weeks later three of the

students were carrying a strain of the meningitis bacteria that was resistant to

the antibiotics.

The issue of time also plays a large role in why this is such a problem

today. Finding a successful new antibiotic that is not related to the already

existent ones takes many years and hundreds of millions of dollars to

accomplish, while ?gene exchange between two bacteria takes less than one

hour.? These two opposing rates make it very difficult to create tough new

medications. The U.S. Food and Drug Administration (FDA) just recently approved

the

release of a new antibiotic, Zyvox, which they warned doctors to be careful

with. Releasing this new drug, the FDA feels as though it is ?like a parent

giving a 16-year

old the keys to the new car.? It is afraid that they will foolishly

prescribe the drug and do more harm than good. It is to be used as a last type

resort, only after other medications are tried first and fail to work. Zyvox is

intended for more serious drug ? resistant staph infections, among other

things, and researchers expect that eventually it too will be confronted with

resistance. Besides this and another new one known as Synercid, there are no

other new antibiotics that are on the near horizon.

Researchers are aware of the many reasons that the issue of antibiotic

resistance is such a problem, and there

are many things that can be done to prevent it from escalating. The solution

has to start with the doctors

themselves, and changing the way that they prescribe the medications. ?As

much as half of all antibiotics are prescribed wrongly, despite recent efforts

to educate doctors and patients.? Patients need to become aware that 80% of

all fevers, inflammations, colds, and flu are a result of viral infections,

which cannot be cured by

antibiotics. Just because you have a few days of fever or two weeks of a sore

throat or cough doesn?t mean you have anything more that a cold. This message

is slowly but surely getting out to doctors and as a result, the rate of

prescriptions written for children under 15 years of age dropped 12% from 1990

to 1998.

Patients also need to stick to the small guns. ?The more an antibiotic is

used, the more likely bacteria are to develop resistance to it.? When you do

in fact need an antibiotic, you are better off using the one that affects the

smallest group of bacteria; one that targets only a particular illness.

Wider-ranged antibiotics on the other hand would subject other bacteria to the

drug and give it more chances to develop resistance.

Many people today believe that more is always better. We are living in a time

where everything is beginning to come with an antibacterial guarantee, such as

scrubs, soaps, mouthwashes, and even toys. ? Many of these products should be

reserved for hospitals and sick patients coming home for treatment; all you need

is soap and water in the healthy household.? Many of these antibacterial

cleansers

do in fact kill some bacteria strains, but they can also strengthen the ones

that survive and cause then to be more dangerous. To avoid the spread of germs,

people should wash their hands before they eat, and also after they use the

bathroom or shake hands. Many viral illnesses are passed by hand-to-mouth and

can be prevented by this.

Another key problem adding to the resistance is the routine feeding of

antibiotics to farm animals. The National Consumer Council (NCC) now is claiming

that the use of antibiotics on farms is reducing their effectiveness to treat

life-threatening human illnesses. ?By weight, half of all antibiotics are

given to livestock and fish in an attempt to prevent disease.? More and more

farmers today are giving their animals antibiotics in order to speed up

growth and to prevent infection and disease where there is intensive

breeding. There is also some concern about the antibiotic residues that are left

behind in meat and then consumed by people. The NCC suggests a ?radical

overhaul? of the current agricultural policy and believes that there should be

more guidelines placed on farmers in order to change the way that they work.

Bacteria, like all other living things, are not carbon copies of each other,

and even within species there are variations. When you take an antibiotic for a

bacterial infection, the most vulnerable bacteria die first, and the least

susceptible will die last. This is an extremely good reason for patients to make

sure they take their antibiotics for the full amount of time that the doctor

prescribes. By only taking it until you feel your symptoms have been relieved,

you may have killed the weakest bacteria, but the strongest ones are still left

and are able to multiply and become resistant. This resistant strain will then

be passes on to other people, thus causing a vicious cycle.

The best way of all to avoid the whole situation of antibiotic resistance is

to not get sick in the first place. This can begin by making sure that you and

your children have all of your immunizations. Also cigarette smoking greatly

increases your vulnerability to bacterial infections, so don?t smoke and if

you do, try quitting. And finally, wash your hands on a regular basis. Doing it

is one of the simplest and most effective tools to top the

spread of bacteria in its tracks. The moral of the story is that not all

bacteria are bad, but it becomes a problem when the dangerous few multiply and

cannot be killed off by our most powerful defenses. ?We should think of

microbes as friends, with a few back-stabbers in the bunch.?

Workes Cited

?Commensal Bacteria are Reservoirs of Resistance.? Roar. Http://www.healthsci.tufts.edu/apua/project

?Farm Practices Threaten Health.? BCC News.

Http://news6.thdo.bbc.co.uk/hi/english/uk/newsid

?How Severe is Antibiotic Resistance?? Http://whyfiles.org/badbugs/scope

Katz, Dolores. ?The War on Antibiotic Resistance.? The Daily Apple. P 1-2

Meyer, Michelle. ?Antibiotic Resistance.? Better Homes and Gardens, March

2001. p 210-15.

?Solving Antibiotic Resistance.?

Http://whyfiles.org/badbugs/Fixes




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