As a vet tech, you will handle antibiotics on a daily basis. But, how much do you really think about those little pills that we prescribe for so many conditions?

Penicillin was discovered in 1928. It revolutionized medical care and was seen by many as a sign that bacterial disease would soon cease to be a threat. By 1940, however, researchers had identified a penicillin-resistant strain of Staphylococcus. Tetracycline was introduced in 1950… and a tetracycline-resistant strain of Shigella was identified in 1959. Methicillin was introduced in 1960; just two years later, in 1962, a methicillin-resistant Staphylococcus strain was identified. Gentamicin was introduced in 1967 and, perhaps unsurprisingly, a gentamicin-resistant Enterococcus strain was identified in 1979.

I think you see the pattern.

The truth is, there are many examples of antibiotic resistance and resistance often arises relatively quickly after an antibiotic is developed and introduced.⁽¹⁾ Antibiotic resistance is a serious issue that poses a threat to both human and animal health. We hear a lot about MRSA (Methicillin-Resistant Staphylococcus aureus), but that is definitely not the only antibiotic-resistant bacterial infection of concern. Approximately 2 million people are diagnosed with antibiotic-resistant infections in the United States each year and approximately 23,000 of these individuals die of antibiotic-resistant infections.⁽¹⁾

How Antibiotic Resistance Develops

Most antibiotic resistance is the result of antibiotic administration serving as a type of “unnatural selection.” Just like natural selection promotes “survival of the fittest” in a given environment, antibiotics exert selective pressures on a bacterial population, leading to an increase in antibiotic-resistant bacteria. 

When an antibiotic is used to treat an infection, only those bacteria that are susceptible to the antibiotic will die. This can result in a small number of antibiotic-resistant bacteria remaining after treatment. If these bacteria survive and reproduce, an antibiotic-resistant infection can occur. This not only affects the animal that is infected with the antibiotic-resistant bacteria, but also any other animal or human to which the infection spreads.

Bacteria can also develop resistance in other ways. Antibiotic resistance genes may be carried on plasmids, which are free-floating DNA that does not reside in the chromosome.

Plasmids can spread from one bacterium to another, allowing the spread of antibiotic resistance genes. 

Bacteria may use a number of different strategies to resist antibiotics. Examples include:

• Block the antibiotic from entering the cell
• Pump the antibiotic out of the cell
• Change or deactivate the antibiotic once inside the cell
• Change cell targets or processes to prevent harmful effects of the antibiotic(²⁾

Antibiotic Resistance: Client Education Talking Points 

One of the primary roles of a vet tech is client education. Given the importance of antibiotic resistance in human and animal health, this is a topic that should be discussed, or at least mentioned, on a regular basis in veterinary clinics. 

Consider the following concepts, which should be conveyed to all clients:

Clients often expect to receive antibiotics for their pets’ illnesses, even in situations when they are not medically necessary. Feline lower urinary tract disease, for example, is a condition for which clients often expect antibiotics, even though they are rarely medically indicated.

While it’s up to the veterinarian to determine whether antibiotics are needed for a given patient, do your part by dispelling the myth that all illness is treated with antibiotics! Pay attention to your language when speaking with clients and educate them on the fact that antibiotics are only appropriate for certain, specific illnesses.

Any time that an infection is treated with antibiotics, the first bacteria to die are the ones that are most susceptible to the antibiotic. If you stop treatment at the first sign of improvement, before you have killed all the bacteria, you will be left with a group of bacteria that are less susceptible to the antibiotic. These bacteria can reproduce and lead to a recurrence of the infection, which may now be antibiotic-resistant.

The only situations where it’s appropriate to finish a course of antibiotics prematurely are:

• Serious side effects
• Additional testing determines that the antibiotic is no longer necessary

Antibiotics are selected to be effective against a particular type of bacteria, at a given dosage, over a given duration. The antibiotic used to treat one dog’s upper respiratory infection is unlikely to be effective in treating another dog’s skin infection. Yet clients do this all the time.

Resist the temptation to just shrug it off when clients tell you they’ve used old antibiotics that they had around the house. Instead, educate the clients! Explain that using ineffective antibiotics, low doses of antibiotics, or short durations of antibiotics increase the risk of causing antibiotic resistance, which may mean that antibiotics don’t work as well for their pet in the future.

Antibiotics that are flushed down the toilet or disposed of carelessly can enter the local water supply. This can lead to low levels of antibiotics circulating in lakes, ponds, and other bodies of water, encouraging the development of antibiotic-resistant bacteria.

When possible, clients should dispose of unused medication through community or pharmacy “take-back” programs. In these programs, the medications are collected and disposed of appropriately. If this isn’t an option, medications going into the trash should be in a sealed plastic container to prevent them from entering the water supply.

Remember…

Although antibiotic resistance may seem like an obvious issue of concern for those of us who work in the veterinary field, it may not be a concept that crosses our clients’ minds on a regular basis. Making brief mentions of antibiotic resistance when the opportunity arises will remind clients of this threat and help them understand how they can combat this problem!

References

1. Centers for Disease Control. About Antimicrobial Resistance. Retrieved from https://www.cdc.gov/drugresistance/about.html
2. Centers for Disease Control. How Antibiotic Resistance Happens. Retrieved from https://www.cdc.gov/drugresistance/about/how-resistance-happens.html