FAO.org

Inicio > Themes_collector > Resistencia a los antimicrobianos > Antecedentes > Preguntas frecuentes
Resistencia a los antimicrobianos

Frequently Asked Questions

1. What are microbes?

1. What are microbes?

Microbes or micro-organisms are very small living not visible with the bare eye. They include bacteria, viruses, parasites, fungi, molds.

2. What/who can they affect?

2. What/who can they affect?

Most microbes are good and useful -- for example bacteria in animal digestive systems that help them absorb food, or bacteria in the soil that help plants take up nitrogen. But others can cause diseases in humans, animals (including terrestrial species, fish and other aquatic animals) and plants. A disease caused by a microorganism is called an infectious disease. Consequences can range from mild illness to death. Some infectious diseases can spread from one host to another: they are contagious and referred to as communicable diseases. 

3. Some microbes can affect more than one host species, i.e.

3. Some microbes can affect more than one host species, i.e.

both animals and humans, or even plants and animals and humans. When humans develop infectious diseases that originate in animals we call them zoonoses. 70% of human infectious diseases are zoonoses, for instance brucellosis, Ebola, Rift Valley fever, tuberculosis, rabies, and ringworm.

4. What are antimicrobials?

4. What are antimicrobials?

Anti means ‘against’, so antimicrobials are drugs that work against microbes. 

5. How are antimicrobials used (antimicrobial use AMU)?

5. How are antimicrobials used (antimicrobial use AMU)?

Antimicrobials is a class of medicines, that include antibiotics. They are used to treat individuals or groups of individuals from pathogenic microbes the diseases they cause. Some antimicrobials kill the microbes ( -cides as in bactericidal), some stop the microbes to grow and spread further (static like bacteriostatic). The use of antimicrobials for their growth promotion properties is now declining and in many countries even forbidden, this is to ensure that antimicrobials are preserved for use as treatment to cure actual diseases (the following points explain why).

6. What is antimicrobial resistance (AMR)?

6. What is antimicrobial resistance (AMR)?

Not all microbes can be killed or stopped to grow and spread by antimicrobials. Some microbes are naturally not susceptible for these antimicrobials, in other words they are resistant. This means that they can ‘resist’ the antimicrobials, and thus continue growing and spreading. Microbes can also develop resistance later, also called acquired resistance: microbes develop resistance to certain antimicrobials that they did not have before. When this happens these antimicrobials cannot be used to treat diseases anymore: this is happening worldwide and causing a health threat.

7. What causes microbes to acquire antimicrobial resistance (AMR)?

7. What causes microbes to acquire antimicrobial resistance (AMR)?

There are several ways: sometimes not all microbes die from coming in contact with antimicrobials: the ones that survive can become resistant and spread this ‘knowledge’ to other microbes. Microbes do not all die from antimicrobials if a treatment was stopped too early or if the dose was lower than prescribed, or if microbes had a chance to ‘get used’ to antimicrobials in the same environment for many times or a long time. 

8. Can antimicrobial resistance affect other hosts?

8. Can antimicrobial resistance affect other hosts?

Yes, if microbes that can cause disease in humans (or other animals) have become resistant to antimicrobials used in animals or crops, these antimicrobials will not be effective in treating that disease in sick humans (or animals).

9. Can we stop microbes from developing resistance to antimicrobials?

9. Can we stop microbes from developing resistance to antimicrobials?

No, we cannot stop microbes from developing resistance, but we can do a lot to prevent this from happening. 

10. How do we know which microbes have become resistant?

10. How do we know which microbes have become resistant?

This is known from laboratory studies and sensitivity testing of one microbe against an array of different medicines – where the pathogen grows, we know that that specific medicine would not be effective. Conversely, where the pathogen does not grow, that medicine can be prescribed o treat the infection if the course of treatment is correctly followed. 

11. How can we prevent the development of antimicrobial resistance?

11. How can we prevent the development of antimicrobial resistance?

We can use antimicrobials responsibly: reduce and regulate their use. This means to use them only when necessary, and only use those that microbes are susceptible for (isolate the microbe that causes the disease in the laboratory and test if it is susceptible for antimicrobials), for the duration and with the dose as prescribed. For the use of treatment in humans and also in animals there exist lists of first, second and last choice antimicrobials for certain microbes. By following these antimicrobial formularies, and not using a last choice antimicrobial before trying a first choice, we can prevent the microbes from acquiring resistance against the last choice (last resort) antimicrobials. 

Compartir esta página