Antibiotic resistance happens when harmful bacteria develop mechanisms that make it harder for antibiotics to kill them.
Antibiotics are medications used to treat infections caused by bacteria, such as urinary tract infections (UTIs) or strep throat.
Misuse or overuse of antibiotics leads to antibiotic resistance. Once bacteria become resistant to an antibiotic, it can be difficult—and sometimes impossible—to kill them. They can remain in your body for years and even pass on their antibiotic resistance to other bacteria.
This article discusses what antibiotic resistance is, how it develops, and the role you can play in preventing it from spreading.
Getty Images | Tetra Images
Understanding Antibiotic Resistance
Bacteria are microorganisms that naturally exist in the environment and even your body. Many are harmless and, in many cases, can even be helpful. Some bacteria, however, can be harmful if they enter your body or touch your skin. They can cause infections, such as:
Bacterial infections are typically treated with antibiotics, drugs designed to kill bacteria or prevent them from growing and multiplying.
If bacteria are overexposed to antibiotics, they can learn how to change their structure or other methods that make it harder for the antibiotic to work. This allows the bacteria to continue living and growing. This results in antibiotic resistance.
Which Groups Are Most at Risk for Antibiotic Resistance?
Antibiotic resistance can affect anyone. In fact, in the United States alone, over 2.8 million cases of antimicrobial-resistant infections are reported each year.
However, certain groups have a higher risk of developing infections with antibiotic-resistant bacteria. These include:
- People on long-term antibiotic treatment
- People with conditions or who take medications that weaken their immune system
- People with pneumonia
- People living in areas with overcrowding or lower access to health resources
- People who are hospitalized or receive care in group facilities
- Adults age 65 years or older
What Leads to Antibiotic Resistance?
Antibiotic resistance occurs naturally as bacteria are exposed to antibiotics and evolve to protect themselves from the effects of these medications.
How Bacteria Fight Against Antibiotics
There are a few mechanisms bacteria use to fight back against antibiotics. They can:
- Keep the antibiotics from entering the bacterial cell: Bacteria can keep antibiotics out of their cells by changing or decreasing the number of entrances for antibiotics.
- Pump the antibiotics out of their cells: Bacteria may use pumps located on their cell linings to push antibiotics out.
- Destroy or change the antibiotic: Bacteria can use proteins to break down antibiotics and inactivate them.
- Change the part of the cell the antibiotics target: Some bacteria can change the part of their cell that antibiotics attach to. If the antibiotic has no target to attach to, it won’t work to kill the bacteria.
When bacteria use any of these mechanisms to combat the effects of antibiotics, they develop antibiotic resistance.
Bacteria that are resistant to antibiotics can multiply and produce more antibiotic-resistant bacteria. They can also pass on this information to other bacteria that have not been exposed to the antibiotic.
They do this by using mobile genetic elements. These include:
- Plasmids: Small, circular molecules that contain bacterial DNA
- Transposons: Pieces of DNA that can move inside bacterial cells and change the cell’s DNA
- Phages: Viruses that swallow bacteria and transfer antibiotic-resistant genes to other bacteria
Mobile genetic elements enable DNA from antibiotic-resistant bacteria to be transferred to other bacteria by any of the following ways:
- Transduction: Phages that transfer antibiotic-resistant genes from one bacteria to another
- Conjugation: Bacteria that transfer resistant genes from one to another by physical connection
- Transformation: Dead or live bacteria that release antibiotic-resistant genes to be picked up by other bacteria nearby
Human Contributions to Antibiotic Resistance
Although bacteria use different mechanisms to learn how to resist the effects of antibiotics, humans also contribute to antibiotic resistance in several ways.
Misuse or Overuse of Antibiotics
Using antibiotics when they are not needed or taking the wrong antibiotic significantly contributes to antibiotic resistance. This is because antibiotics not only kill harmful bacteria, but they can also kill helpful bacteria that may protect you from the harmful bacteria. When helpful bacteria die, harmful bacteria are able to develop resistance mechanisms and multiply more easily.
Not taking the correct dose of an antibiotic can also contribute to antibiotic resistance. Antibiotics are designed to kill bacteria at a certain dose and for a certain amount of time. Taking doses lower than the prescribed dose or waiting too long between antibiotic doses allows for some bacteria to survive the antibiotic treatment. These bacteria can develop antibiotic resistance and spread their genes to other bacteria.
Stopping your antibiotic before the prescribed number of days can also allow for some bacteria to survive and become resistant.
How Long Does Antibiotic Resistance Take?
Bacteria have been adapting and developing antibiotic resistance since penicillin, the first antibiotic, was discovered more than 80 years ago. As new antibiotics have been developed, bacteria have continued to adapt to combat the effects of antibiotics.
Antibiotic resistance can take a few years to decades to develop, depending on how the antibiotic works, how widely it’s used, and how easily bacteria can develop resistance mechanisms. Slowing down antibiotic resistance is possible by using antibiotics appropriately and only when needed.
What Are the Results of Antibiotic Resistance?
Antibiotic resistance is a worldwide issue that can have serious consequences.
Many antibiotics are used to treat serious infections, such as pneumonia or strep throat. However, if these infections are caused by antibiotic-resistant bacteria, healthcare professionals must use alternative antibiotics to treat them.
Sometimes, these antibiotics may cause serious side effects, such as kidney problems, severe diarrhea, or allergic reactions, for some people. Some alternative treatments may not work as well as the original antibiotic. And for some infections, there may not be an alternative antibiotic. This may lead to extended hospital stays, worsening illness, and even death.
Healthcare professionals rely on antibiotics to prevent infections during cancer treatments, dental procedures, and surgeries, such as cesarean sections (C-sections), organ transplants, and knee or hip replacement surgeries. Antibiotic resistance limits the number of antibiotics available for these purposes and increases the risk of people developing hard-to-treat infections during or after these procedures.
Antibiotic-resistant infections take longer to treat and may require people to remain hospitalized longer than usual. This, in turn, increases their risk of developing other infections.
What Can You Do to Prevent Antibiotic Resistance?
Antibiotic resistance is a worldwide problem that requires collaboration from everyone to help control it.
You can do your part to help protect yourself from antibiotic-resistant infections and help slow down their spread.
The following are a few safe practices to follow to help minimize antibiotic-resistance:
- Wash your hands regularly with soap and water.
- Only use an antibiotic for the infection it was prescribed to treat.
- Do not use antibiotics for viral infections, such as the flu or common cold. Antibiotics kill bacteria, but not viruses.
- Take your antibiotic doses regularly with evenly spaced time intervals between doses when awake.
- Finish your entire course of antibiotic treatment even if you start to feel better after a few days.
- Do not share your antibiotics with others or use someone else’s antibiotics.
- Do not save or take leftover antibiotics. Instead, find ways to dispose of leftover antibiotics safely.
Summary
Antibiotic resistance is a worldwide problem that happens when bacteria develop ways to combat the effects of the antibiotics designed to kill them. People do not become resistant to antibiotics. Instead, bacteria naturally develop mechanisms that make it difficult for antibiotics to kill them. For example, bacteria may develop ways to prevent antibiotics from entering their cells or pump antibiotics out of their cells.
Once bacteria become antibiotic-resistant, they can pass on their genes to other bacteria that also become resistant. Antibiotic resistance limits the antibiotics available to treat serious infections. This can result in longer recovery time, increased risk of additional infections, and even death.
For this reason, it’s important to follow guidelines for appropriate antibiotic use. This includes taking antibiotics exactly as your healthcare provider prescribes them and not sharing your medication with others.
