Antimicrobial or antibiotic resistance is a phenomenon when bacteria evolve over time, change and no longer respond to drugs that usually destroy them. This ultimately makes it more difficult to treat infections and increases the risk of disease, illness and death spreading among the population. The World Health Organization has declared antimicrobial resistance as one of the ten biggest global threats to health.

Scientists are trying in different ways and from different samples to develop new antibiotics, and even completely new therapies for bacterial infections (such as therapies for bacterial infections using viruses that destroy bacteria – bacteriophages) that could save the situation. If they don’t find new therapies for these infections, humanity is entering the post-antibiotic era when we are actually going back to the 19th century and before – a time when there were no antibiotics.

How antibiotics work?

Antibiotics work by inhibiting the growth or destroying bacteria. They do this in different ways, such as destroying the bacterial cell wall or inhibiting the production of energy from glucose inside the bacterial cell.

We already have tuberculosis resistant to antibiotics (Drug-resistant TB, DR-TB), gonorrhea resistant to multiple antibiotics, methicillin-resistant staphylococcus aureus ( MRSA ), and there are other resistant strains.

Almost half a million people who developed tuberculosis in 2019 had resistance to rifampicin , a key first-line drug for the treatment of tuberculosis.

Antibiotic resistance occurs due to mutations in the DNA of bacteria or the acquisition of antibiotic resistance genes from other bacterial species through horizontal gene transfer. These changes allow the bacteria to survive the effects of antibiotics designed to kill them.

This means that when an antibiotic is used, all bacteria that have not undergone mutation are killed, while antibiotic-resistant bacteria remain unchanged. Antibiotic-resistant bacteria can continue to divide and grow, creating even more bacteria that the antibiotic doesn’t work on.

Why is this happening?

Well, we’re to blame. These are the main reasons:

  • excessive use of antibiotics, use of antibiotics without a prescription (these drugs are issued only by prescription, but unfortunately, there is a practice of giving them without a prescription as well)
  • the use of antibiotics to treat viral infections
  • some people stop taking antibiotics when they feel better and this leads to the development of resistant strains and increases the chance that some bacteria will survive and become resistant
  • another form of improper use of antibiotics: the use of unused antibiotics from a previous infection
    prescribing antibiotics without a previously performed antibiogram
  • prescribing antibiotics as a preventative in case of viral infections to prevent secondary bacterial infection (unfortunately, doctors are sometimes prone to this)
  • excessive use of antibiotics in livestock and poultry, to achieve faster growth of individuals and prevent diseases where animals are densely packed.

What can we do?

  • use antibiotics only as indicated
  • finish the antibiotic therapy as recommended and do not leave “a couple of pills” for later
  • do not take antibiotics for viral diseases because antibiotics do not work against viruses
  • more education of doctors to be sparing and careful with prescribing antibiotics and not to prescribe these drugs when they are not needed
  • vaccination against those diseases caused by bacteria for which there are vaccines
  • reduce the use of antibiotics in the breeding of animals for food, for example by breeding where the animals are less crowded in a small space, better management of farms.



Jelena Kalinić, MA in comparative literature and graduate biologist, science journalist and science communicator, has a WHO infodemic manager certificate and Health metrics Study design & Evidence based medicine training. Winner of the 2020 EurekaAlert (AAAS) Fellowship for Science Journalists. Short-runner, second place in the selection for European Science journalist of the year for 2022.