Since their discovery in the 1920s, the world hailed antibiotics as one of the greatest medical advancements in history. However, overuse and misuse of these powerful medications have created a new challenge for health care providers — antibiotic resistance.
Antibiotic or antimicrobial resistance occurs when bacteria change and no longer respond to the medications that once killed them or slowed their growth. These drug-resistant bacteria may multiply and spread, putting people at risk for more serious infections that are difficult, or even impossible, to treat.
The rapid spread of resistant bacteria is occurring worldwide, with nearly 3 million antibiotic-resistant infections occurring in the United States each year. Unfortunately, around 35,000 people die as a result.
Doctors and the general public must do their part to reduce antibiotic resistance. Here's what you need to know.
What is antibiotic resistance?
Antibiotic resistance doesn't mean that your body is resistant to antibiotics. It means the bacteria causing an infection are unaffected by the antibiotic treatment.
Bacteria have been around for millennia, evolving into different strains as they become exposed to new things in their environment, including antibiotics.
The antibiotic resistance seen in today's bacteria arises from selection pressure. In other words, only those bacteria that can survive and even thrive in the presence of antibiotics continue to multiply. These microbes have resistant traits in their genetic material that can spread to other bacteria.
For bacteria to survive, they must develop ways to outsmart antibiotics, called resistance mechanisms. Bacteria can become resistant by:
- Producing enzymes that destroy the antibiotic.
- Changing the structure of their cell wall so the antibiotic can't attach to it.
- Pumping the antibiotic out of their cells before it has a chance to work.
- Restricting access so the antibiotic cannot enter the cell membrane.
If difficult-to-treat bacteria have a combination of these resistance mechanisms, it could mean that multiple or all antibiotics are ineffective, leading to untreatable infections.
Antibiotic-resistant bacteria can pass their resistance mechanisms to other bacteria that haven't yet encountered antibiotics.
Once antibiotic resistance emerges, it can rapidly and easily spread to new hospitals, clinics, and other settings and between countries.
What causes antibiotic resistance?
Antibiotic resistance occurs because of how people use antibiotics, including overuse, misuse, inappropriate prescribing, and agricultural use.
Overusing antibiotics drives the evolution of antibiotic resistance. When populations take antibiotics unnecessarily, it gives bacteria more opportunities to become resistant.
Because bacteria can inherit genes from relatives and nonrelatives, it allows them to transfer antibiotic resistance to different species of bacteria. Also, some mutations that cause resistance can occur randomly.
In many countries, you can buy antibiotics easily over the counter without a prescription. However, because there is no regulation and antibiotics are easily accessible, people can overuse them.
Even in countries where antibiotics are only available with a prescription, doctors may prescribe them too readily. Research shows that doctors prescribe antibiotics unnecessarily up to 50% of the time.
Bacteria multiply at any opportunity. Therefore, not taking antibiotics according to your doctor’s instructions allows resistant bacteria to grow. This includes:
- missing doses
- stopping the course early
- using the incorrect dosage
Bacteria can reproduce and mutate if you use unsuitable antibiotics, such as someone else's medicine. If antibiotics only partially kill the bacteria, they survive and multiply, and the population of drug-resistant bacteria grows.
Doctors should prescribe antibiotics carefully and responsibly. Good antibiotic stewardship involves a correct diagnosis of the condition requiring treatment and the proper choice of antibiotic and course duration.
Incorrectly prescribed antibiotics may not have any benefits, and they expose people to potential complications. If the prescribed therapy doesn't inhibit the bacteria, it can promote antibiotic resistance by allowing the bacteria to mutate.
Extensive agricultural use
Around the world, farmers use antibiotics as animal growth supplements and to prevent disease. Approximately 80% of antibiotics sold in the U.S. are to produce larger yields and better products from livestock.
The antibiotics used in animals also kill or suppress susceptible bacteria, allowing antibiotic-resistant bacteria to thrive. As a result, when people eat meat or products from animals treated with antibiotics, they encounter resistant bacteria. These bacteria can then cause infections that are difficult to treat.
Agricultural antibiotic use also affects the balance of bacteria in the environment. Animals excrete almost all antibiotics in their waste, which disperses through fertilizer, groundwater, and surface runoff. Microorganisms in the environment then become exposed to resistant bacteria, which alters the delicate balance of the ecology.
Can you prevent antibiotic resistance?
Everyone can play their part in helping prevent antibiotic resistance. Here are some tips:
- Take antibiotics only as directed by your doctor and follow any other instructions they provide. This includes taking the full course of treatment as prescribed, even if you feel better before the end.
- Remember to take your doses on time. You can set a timer to remind you when to take your antibiotic, so you don't miss any.
- Do not take someone else's medications. Avoid sharing antibiotics with others or using leftover antibiotics.
- Do not use antibiotics to try to treat viral illnesses, such as colds or the flu.
- Prevent the spread of infection by practicing good hygiene. You should wash your hands frequently, especially before eating and after using the bathroom. Also, cover your mouth when you sneeze or cough and clean surfaces that germs may have contaminated.
- Prepare food safely by cleaning fresh produce, separating raw and cooked foods, heating food to the recommended temperature, and keeping food correctly refrigerated or frozen.
Doctors and healthcare providers can also help by:
- Prescribing antibiotics responsibly and only when needed.
- Using antibiotics that suit the specific bacteria involved.
- Only prescribing antibiotics for as long as necessary.
- Using good hygiene to control the spread of infections in clinics and hospitals.
Reducing the use of antibiotics in livestock is also important. This involves using vaccines and other preventive measures to keep animals healthy and only using antibiotics when necessary. Farmers and ranchers should also follow instructions carefully when using antibiotics and only use them on the advice of a veterinarian.