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Antibiotics in Society:

Effects of Antibiotics in Animal Agriculture, the Environment, and in Hospitals on Superbugs

Lauren Dunn

University of Tennessee at Chattanooga

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Introduction:

Antibiotics are one of the most impressive creations in the scientific field due to their

impact on not only human health but also the agribusiness industry. Antibiotics are used today to

treat human sicknesses in a variety of diseases including ones that used to be incurable as well as

their role in the agribusiness industry to meet the demand for animal products. Having such a

powerful drug for curing illnesses and other uses seems like it is too good to be true; that is

because it is. While there are many advantages to using antibiotics, there is one crucial

disadvantage as well: antibiotic resistance.

If you have had a child that received a cut from playing in the yard back before the

1940s, odds are the cut would become infected, and the child would die. Any type of bacterial

infection before the 1940s had a similar result. Alexander Fleming is the one to thank for the life

expansion of those with bacterial infections due to his monumental work in discovering

penicillin, the first given antibiotic. After Fleming’s discovery was made and gained the FDA

approval, doctors began prescribing antibiotics for every illness, disease, and problem that came

through their doors, but it was shortly after the discovery that doctors saw its flaw of resistance.

Today, this issue is more important than ever because the more antibiotics are used, the more

bacteria adapts to them resulting in antibiotics that no longer work. Bacteria have had about 75

years to continually adapt to the antibiotic treatments, and the rapid use of antibiotics in society

means the effectiveness of antibiotics become slimmer and slimmer until there are no more

antibiotics that work. This is the creation of the antibiotic superbug.

This paper is going to discuss the effects of not only antibiotics on human health, but the

effects of the agribusiness industry as a whole on our society by discussing bacterial processes

and functions, antibiotic processes and functions, antibiotics in society—including the

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agribusiness industry, the environment, and the medicinal use—and it will finish with a

discussion on superbugs.

What are bacteria?

Bacteria have been around since the beginning of time, and being the oldest lifeform on

earth, they are a big deal. Bacteria are single-celled organisms that live all over everything and

can benefit or harm the human body (U.S.). They come in three different shapes—coccus,

bacillus, and spirochete—and have different cell wall types (Goldsmith 13). The work done on

bacteria over the years has told us about the variation of these small creatures including that their

cell wall type determines how they respond to bacteria, that they adapt to the environment just

like humans and other organisms, and that their genes can mutate just like humans’ genes can

(15). Bacteria reproduce and pass on their genes through transduction, transformation, and

conjugation sometimes resulting in a random genetic mutation that gives the bacteria some sort

of survival advantage (47). These mutations are ones that benefit the bacteria cells but could

harm humans. Christopher Walsh explains, “Typical antibiotics in doctors’ arsenal today aim to

kill bacteria by interfering with some aspect of their essential life functions,” (46). The passing

of genes in cell processes can be disrupted in five ways including interference with the

construction of bacterial cell walls, disruption of cellular processes, weakening of the ability for

the bacteria to take in nutrients or rid toxins, prevention of DNA replication, and mocking

nutrients needed by the bacteria (36-37). While most bacteria are harmless, some bacteria can

causes diseases. The combination of gene mutation and instinct for survival is a deathly

combination for humans in today’s world because the antibiotic superbug is on the rise. The

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more antibiotics are put into our society, the quicker they will become resistant to bad bacteria

causing the antibiotics to stop working properly.

The role of antibiotics:

Antibiotics are the flip side of bacteria; they are beneficial to humans but harmful to

bacteria…most of the time. According to the Centers for Disease Control and Prevention (CDC),

antibiotics are defined as, “Drugs that fight infections caused by bacteria in both humans and

animals. Antibiotics fight these infections either by killing the bacteria or making it difficult for

the bacteria to grow and multiply.” Antibiotics disrupt bacteria cell processes, which prevent or

rid sickness in humans and animals as well as promote animal growth in the agribusiness

industry. They can be created from molds, bacteria, or synthetic compounds (Jaiswal, Suresh,

Pandey, and Raju 2012, 665). There are two broad categories of bacteria types: bacteriostatic and

bactericidal. Bacteriostatic slow down the bacteria’s rate of multiplication while bactericidal kills

off bacteria completely (Goldsmith 36). Each type is used for medicinal purposes but bactericidal

are more common. Antibiotics can be broken down even more to five general categories

including cell wall inhibitors, inhibitors of nucleic acid synthesis, inhibitors of protein synthesis,

anti-metabolites, and antibiotics that damage the cell’s membrane (Jaiswal et al.2012, 666). The

helpfulness of antibiotics has been a success ever since they were invented, but today, scientists

are trying to keep antibiotics doing more good than bad and avoid the superbug.

The relationship between antibiotics and bacteria is a fragile one because the more

antibiotics are used the more bacteria adapt and become resistant contributing to the superbug.

Julian Davies defines the term superbugs as, “microbes with enhanced morbidity and mortality

due to multiple mutations endowing high levels of resistance to the antibiotic classes specifically

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recommended for their treatment,” (Davies 419-420). The problem of antibiotic resistance was

first discovered in the late 1940s, but doctors dismissed the issue (Goldsmith 41). Today, it is

more of an issue than ever because they are used more often. Antibiotics can be found in creams,

liquids, lotions, medicines, syrups, tablets, injections, and even your meat (Jaiswal et al. 2012,

665). The number of ways people can use antibiotics is astonishing, and they all contribute to the

rise of the superbug because bacteria fight against the antibiotics by “deployment of an enzyme

that destroys or disables the antibiotic drug; use of a pump in the cell wall that excretes the drug

before it can work; and replacement of the drug’s target protein with a variant version the drug

cannot recognize,” (see figure 1) (Walsh 47). Two of the most common ways to use antibiotics

are through antibiotic medicines and the agribusiness industry.

Antibiotics and the agribusiness industry:

Agribusinesses are just like any other business which means the goal is to maximize

profits and minimize costs despite the consequences. In this industry’s case, the consequences

mean mass production of animals, which creates problems with animal health, environmental

Figure 1 http://nizetlab.ucsd.edu/News/Sci-Amer-Superbugs.pdf

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health, and human health. While mass production is a great method to meet a demand, it is not

necessarily the most effective method for the agribusiness industry due to the ramifications that

typically accompany the cheap meat prices. The side effects of the agribusiness industry may

come as a shock to the general public because the disadvantages outweigh the advantages of the

low cost products this industry creates. One of the greatest shocks may come from the use of

antibiotics in the agribusiness industry since they are used in other farm practices besides treating

sick animals such as being growth promoters in animal feed. Over 84 percent of the antibiotics

used in the United States are used in livestock food causing the population’s antibiotic usage to

increase (Goldman 122). One of the reasons for antibiotics includes medicinal purposes. As a

result of the farming practices factory farms use including battery cages, gestation crates, and

farrowing crates, combined with the close confinement of the animals, the animals are bound to

get sick. They become deformed due to the small spaces they live in; they never see the sunlight

(in most cases) and lack vitamin D; and they are under immense pressure, so their stress levels

rise. This all contributes to sickness. The close quarters of the animals ensures that if one animal

gets sick, all of the animals of that species get treated too to avoid spreading the disease.

However, the main use of antibiotics on a factory farm comes from their use as a growth

promoter. Antibiotics in an animal’s food source promote more of the vitamin B12 to an animal,

but they also increase the growth rate of the animal (Goldsmith 66). Today, chickens that are

used for meat take only 39 days to reach slaughter weight compared to the 14 weeks that it took

in the 1940s (see figure 2) (“Animal Welfare”, par 26). Beef cows are bred to reach anywhere

between 1,000 to 1,500 pounds (par 13). The same principle is applied to dairy cows as well. Just

less than 20,000 pounds of milk are produced per cow today while in the 1950s that number was

around 5,300 pounds (par 11). Antibiotics used as a growth promoter create an environment for

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antibiotic resistant bacteria to thrive. Emanuel Goldman explains, “Bacteria also can rapidly

transfer and spread antibiotic-resistance to other bacterial species. Therefore, diseases not even

related to food become resistant to antibiotics…” (121). So even though antibiotics are used to

treat sick animals, their main role in factory farms comes from promoting growth in the animals

and results in detrimental effects.

Antibiotics in the environment:

Antibiotics found in the environment are another way that antibiotics are contributing to

the super bug. The antibiotics found in the environment typically result from factory farms,

hospitals, and domestic practices because their waste gets stored in containers called lagoons or

runs through urban wastewater treatment plants (UWTPs) (Michael et al 958). Lagoons store

animal waste from factory farms, and the waste is used as fertilizer. The lagoons can also leak

causing the manure to run into water ways (Goldsmith 84-85). The waste used as fertilizer

houses antibiotics that left the animals’ bodies from the feed the animals ate. This is sprayed onto

vegetable crops to help them grow, and if not washed properly, the vegetables can still have

Figure 2 https://www.youtube.com/watch?v=PVyxMXHbTio

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antibiotics on them when you eat them, which contribute to an increase in antibiotic resistance.

When the lagoons leak, the antibiotic-filled manure ends up in surrounding waterways causing

the antibiotics to be present in the streams, rivers, or lakes that could be used as drinking water.

Even if humans are not the ones to drink the water, domestic animals could drink from the water

and bring the antibiotic resistant bacteria back to the household (Goldsmith 84-85). Using the

UWTPs, antibiotics can still end up in the environment despite their 3 stages of filtration (see

figure 3). UWTPs have a primary, secondary, and tertiary stage of the filtration process (Michael

et al. 259). The primary stage consists of filtering out solid materials such as sand, grit, and

waste while the secondary stage is focused on extracting nutrients or organic matter. The tertiary

portion of filtration includes removing phosphorous from the water (259).

Figure 3 http://engineering.nyu.edu/k12stem/sosc/curriculum/urban-infrastructure/water-recycling-and-treatment/

Michael describes, “Elimination and transformation of antibiotics during the biological

treatment is the result of different processes…the removal of antibiotics mainly depends on their

sorption in on the sewage sludge and their degeneration or transformation during the treatment,”

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(259). The issue of antibiotics in our water is that conventional water filtration systems are not

created to remove antibiotics from the water. Advanced treatments can be used to remove more

antibiotics before returning the water into the environment, but it is more costly and does not

ensure that all the antibiotics will be detached (Michael et al. 986). There are other ways that

antibiotics can fill the environment, but these are just ways that the agribusiness contributes to

the environmental antibiotic problem.

Antibiotics in hospitals:

Antibiotics in the agribusiness industry go hand-in-hand with antibiotic usage in hospitals

due to the fact that they are the two most utilized sources of antibiotics. Hospitals are one of the

most, if not the most, common place for antibiotics, since antibiotics are solely used to treat sick

patients. The growing worries with antibiotic usage and the creation of the superbug are most

influential in this industry because of human health concerns. As Georgina Casey explains,

“Infections occur more often in hospitals because in hospitals there are: Vulnerable

populations with impaired immunity, impaired epithelial barriers (due to surgery, injury

or penetrating medical devices) and in close proximity to each other; multiple encounters

with a wide variety of health-care professionals; Higher numbers and greater variety of

microorganisms,” (21).

These factors allow an increase in antibiotics used. The goal of using antibiotics is to fight off an

infection by reducing the number of bacteria and to allow a person’s immune system to eradicate

the remainder of the infection on its own (22). There are three main components to determining

the dose of antibiotics needed for a treatment: time dependent killing, concentration-dependent

killing, and post-antibiotic effects, and while many superbugs are contained in hospitals, there is

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an accepted understanding that all antibiotics will become resistant at some point (22-23). Amal

Alsaeed documents, “Sivert et al. reported on antimicrobial resistant pathogens associated with

healthcare associated infections: eight pathogen groups represented 80% of reported pathogens,”

(304). One of the biggest pathogen problems within the healthcare field results from MRSA

(methicillin-resistant S. aureus). “Acquisition of the mecA gene results in the encoding of a

novel penicillin-binding protein that is biologically active but not inhibited by β-lactam

antimicrobials,” Alsaeed explains. “Resistance is rendered to penicillins, cephalosporins,

monobactams and carbapenems,” (304). MRSA is constantly increasing in difficulty to fight off

because of the overall antibiotic resistant bacteria are on the rise too (Enright 7687). Back in

1959, methicillin was introduced in order to treat infections that resulted from penicillin-resistant

genes, and two years later, worldwide reports deemed methicillin resistance in certain isotopes

(Enright 7687). Today, a plethora of strains have adapted to hospital environments making them

nearly impossible to wipe out (7687). Nonetheless, this resistance moves beyond the hospitals

and can be spread to places where people work, play, or live (Goldsmith 54). The combination of

antibiotic usage in hospitals and factory farms is the main reason for the antibiotic superbug.

The superbugs:

All of these encounters with antibiotics play into the health of humans. The agribusiness

industry feeds their animals antibiotics, those antibiotics are in the animals’ bodies, the

antibiotics are in the meat produced by the animals, and then humans consume that meat. In

addition, the waste from these animals gets stored in lagoons, then that waste is used as fertilizer,

and as a result, antibiotics end up in run off to the waterways, and if that is not enough, when

illness occurs, people seek out antibiotics to kill off infections from doctors. All of these factors

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contribute to the rise of the superbug, which puts humans at risk of incurable diseases (see figure

4). Infections such as Staphylococcus epidermidis, Streptococcus pneumoniae, and Salmonella

enterica, among others, are some of the common strain that are increasingly becoming resistant

to antibiotics (Davies 419). Davies and Davies informs, “The most prevalent Gram-negative

pathogens, such as Esch-erichia coli, Salmonella enterica, and Klebsiella pneumoniae, cause a

variety of diseases in humans and animals, and a strong correlation between antibiotic use in the

treatment of these diseases and antibiotic resistance development has been observed over the past

half-century,” (420). On the other hand, the biggest Gram-positive superbug today is

Staphylococcus aureus (420). Due to the health risks from superbugs, necessary precautions

should be made in order to slow down the risks such as enhancing the development of new

antimicrobial agents, reducing transmission, and reducing the rate of resistance development

(Casey24). While the most critical superbug is debatable, Davies and Davies believe it to be

Vibrio cholera, and here is why:

“Superbugs are omnipresent in the biosphere; their consequences are aggravated

enormously in volatile situations such as civil unrest, violence, famine, and natural

disasters and, of course, by poor or nonexistent hospital practices. Superbugs are not the

only microbial threats, but they are recognized as the most menacing with respect to

morbidity and mortality worldwide. In terms of the number of infections and

consequences, Vibrio cholera should be at the head of the superbug list,” (421).

Regardless of the “top superbug”, all steps for prevention should be taken in order to slow down

the rate of resistance of antibiotics.

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Prevention:

The problem with antibiotics is that at one point or another, bacteria will become resistant

to them, and they will stop working. However, there are some ways to slow down the superbug.

First and foremost, humans need to be cautious of their antibiotic intake. One should always

discuss antibiotic usage with his or her healthcare professional before usage; ask the doctor about

remedies that do not use antibiotics, and ask the doctor about vaccinations that can be used to

prevent infections that need antibiotics (U.S.). In addition, one should always take his or her

antibiotics as prescribed; do not share the medication with others, do not end use of the

medication early, and take as directed by the prescriber to be sure the infection is killed off

Figure 4 http://mmbr.asm.org/content/74/3/417/F4.large.jpg

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completely (which does not leave room for bacteria to live and become adapted to the

antibiotics) (Aminov 4, U.S.). Therefore, healthcare professionals should always discourage the

use of antibiotics when they can be avoided, educate their staff on when/how to use antibiotics,

and prescribe antibiotics only when it will benefit a patient (U.S.). Countries neglecting

antibiotic regulation call for the personal discretion of the patient in deciding when to use

antibiotics. This results in incorrect dosages, medications, and improper diagnosis which

contribute to the problem (Aminov 5). In the agribusiness industry, farms should limit the use of

antibiotics to strictly medicinal use and not for promoting growth in the animals. Scandinavian

countries have adopted this practice and have had success in slowing down the antibiotic

resistance rate (5). Probiotics, bacteriophages, antimicrobial peptides, and transmission reduction

are also ways to reduce or prevent antibiotic resistance. Probiotics are only successful in killing

bacteria in certain situations, but they can be used to counter the effects of pathogens. The

chemicals and functions of bacteriophages can be used to fight off viruses as well since

bacteriophages are viruses that infect bacteria. Furthermore, antimicrobial peptides work by

disrupting pathogen membranes which ends up killing the pathogens. Lastly, taking vaccinations

when possible to prevent future bacterial infections is necessary to reduce transmission of

diseases (Casey 24). All of these ideas can help slow down the superbugs and keep antibiotics

working longer.

Conclusion:

Alongside other problems in today’s world, antibiotic resistance is right there at the top

of the list. The relationship between bacteria and antibiotics is one that has been delicate ever

since Alexander Fleming first discovered penicillin. The expectation that antibiotics will always

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cure illnesses is a reality that does not exist, and people need to be more aware of the risks of the

future. Whether the antibiotic intake comes from agriculture, waterways, medicinal use, or in any

other form, precautions need to be taken any time antibiotic use is in the picture. By taking the

necessary steps and increasing knowledge on this issue, the rate of the superbugs can be slowed

down, and diseases can remain curable for longer.

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Davies, Julian, and Dorothy Davies. "Origins and Evolution of Antibiotic Resistance."

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