Antibiotic Resistance: Why Does It Appear?

Antibiotic resistance is one of the biggest threats today, as it makes curing certain diseases more difficult. Keep reading to learn more.
Antibiotic Resistance: Why Does It Appear?

Last update: 12 April, 2023

Bacteria are one of the most frequent pathogens in medical practice and are capable of causing a large number of infections. The most effective treatment is the administration of antibiotics. However, various species have been able to develop antibiotic resistance.

Antibiotics are medicines discovered in the 20th century that are effective in treating various infections. These drugs use multiple mechanisms to eliminate bacteria, ranging from the destruction of their cell wall to the alteration of the plasma membrane.

According to the World Health Organization (WHO), antibiotic resistance is one of the greatest threats on a planetary level. It has caused the appearance of diseases that are more difficult to cure, in addition to lengthening the stay of patients in hospitals.

What is antibiotic resistance?

This dire situation occurs when bacteria develop the ability to survive the drugs designed to kill them. In this regard, the microorganisms change in response to the drug, becoming able to resist its effect.

At present, antibiotic resistance reaches alarming numbers in all parts of the world. A tangible example of this situation occurs with a bacterium called Staphylococcus aureus, capable of causing skin infections and pneumonia. These diseases were treated with penicillin for many years.

In the year 1940, a strain of Staphylococcus aureus was discovered that was capable of resisting the effect of penicillin. The situation with this bacterium in particular has worsened over the years and studies state that 90% of the strains currently isolated are resistant to the drug.

The effects of antibiotic resistance on bacteria are highly varied. This problem causes the appearance of more serious and lasting diseases. What’s more, it can also generate longer contagion times and more severe side effects.

Various bacteria.
Bacteria develop mechanisms to resist the action of antibiotics through mutations.

Types of antibiotic resistance

Since antibiotics were discovered, their mechanism of action has been studied in order to describe how the compounds are capable of eliminating bacteria. In this regard, it was found that the same drugs weren’t effective in all cases.

At the same time, it was also discovered that they could lose their effectiveness over the years. In this way, two types of resistance to antibiotics have been described:

  • Intrinsic resistance: This is the resistance of the bacterium itself, which has physical or chemical characteristics that make the drug have no effect.
  • Acquired resistance: Occurs when a bacterium that was previously sensitive to an antibiotic develops the ability to protect itself from it, inactivating and rendering its active ingredient useless.

Acquired resistance is the most dangerous of all, as the information can be passed on to a new strain. This type of antibiotic resistance is what has wreaked havoc on the health system worldwide.

Why does antibiotic resistance occur?

This great health problem occurs due to frequent and prolonged exposure to the effect of antibiotics, according to research. In this regard, when bacteria are in constant contact with a drug, they’re capable of developing various defense mechanisms.

At the same time, it should be known that bacteria have a part called the pilus, which is in charge of transmitting information. In this way, resistant strains are able to pass on the defense mechanism to others, which worsens the situation.

It’s important to remember that bacteria are commonly found in the body, both on the skin and in some organs, which are known as microbiota in said presentation. With this in mind, various practices increase the risk of developing antibiotic resistance. We’ll discuss them below.

Taking antibiotics when they aren’t needed

Some people take broad-spectrum antibiotics to treat conditions such as plaques in the throat without consulting a specialist. Many of them are caused by a virus, so the administration of these drugs isn’t necessary.

This problem occurs especially with broad-spectrum antibiotics that don’t require a prescription. They kill all sensitive bacteria when consumed, thus increasing the resistance of germs that remain in the body.

In this regard, the best thing to do in the face of any infectious process is to go to a professional. Only doctors are capable of prescribing the right drugs to cure the condition.

Medicines must be administered in precise doses so that they can produce the desired effect, and antibiotics are no exception. In this regard, the drug won’t completely eliminate the bacteria when the recommended dose isn’t ingested, which increases the probability of developing acquired resistance.

Therefore, it’s crucial to follow the instructions of a specialist to the letter, both regarding the dose and the administration schedule. Only then will it be possible to eradicate the infection and avoid complications in the future.

Exposure in food and animals

Antibiotics are also used in agriculture and veterinary medicine to kill bacteria that affect plants and animals. These microorganisms have the same ability to develop resistance to prolonged exposure. Also, some of them are capable of infecting humans.

A culture of drug-resistant bacteria.
Bacterial colonies can develop resistance and transmit it to other strains.

Mechanisms of antibiotic resistance

Bacteria have been capable of developing multiple mechanisms to resist the action of the most common antibiotics, such as azithromycin. One of these mechanisms is the restriction of drug entry, as some drugs must enter the cytoplasm in order to act.

On the other hand, microorganisms can allow the entry of the antibiotic, but with the ability to expel it later. Another of the most studied processes is enzymatic inactivation, through which the bacterium is capable of producing enzymes that destroy the drug before it exerts its action. Bacteria are also capable of altering the specific part upon which the antibiotic will act.

A health problem that must be combated

Antibiotic resistance affects millions of people around the world. According to data released by the Centers for Disease Control and Prevention (CDC), at least 2.8 million Americans develop infections from resistant bacteria each year. This fact highlights the importance of taking action in this regard.

In this way, these drugs should only be ingested with prior medical authorization and with the recommended doses. Also, containers and expired medications should always be disposed of safely.

This is a health problem that affects all people without making any kind of distinction. For this reason, we must be aware of the use of antibiotics and the serious effects that their inadequate intake can cause.

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