What is antibiotic resistance?
Antibiotic resistance refers to bacteria and it is particularly important when these are pathogens. In such a case, antibiotic therapy will fail. Hence, “antibiotic resistance” is a human- and animal health issue. However, antibiotic resistance has been regarded as biological pollution that can occur and spread in the environment, and be returned to humans and animals.
What does it mean when bacteria are resistant to antibiotics?
It means that they will be able to proliferate in the presence of the antibiotic, meaning that the therapeutical agent is useless. More info...
What are “Superbugs”?
“Superbugs” is a non-scientific word that refers to bacteria that have the capacity to proliferate in presence of different types of antibiotics, leaving the doctors very limited or no alternatives to treat bacterial infections. In technical terms, a superbug refers to a multidrug-resistant bacteria, defined as those able to resist antibiotics that belong to at least three different classes. In extreme cases, a superbug may be resistant to all the antibiotics available.
How does antibiotic resistance happen?
It can be an intrinsic property of bacteria, related to their structure or metabolism. In other cases it can be acquired when bacteria gain new genetic information, which normally occurs through horizontal gene transfer, meaning that it is the passage of genetic material between contemporaneous cells. This contrasts with the vertical gene transfer corresponding to the transmission of genetic material from ancestors to progeny. Antibiotic resistance may occur by different mechanisms. See also Mechanisms of antibiotic resistance
Is antibiotic resistance an important issue?
Antibiotic resistance can affect anyone, of any age and in any country. In Europe, where good health and sanitation conditions are in place, can kill about 30 000 people per year. Moreover, antibiotic resistance leads to increased medical costs, prolonged hospital stays failure of medical interventions, and higher mortality. For all these reasons it has become a subject of major concern for public health authorities.
What is the single most significant factor driving increasing rates of antibiotic resistance?
The factor pointed as most significant is the use of antibiotics. For that reason many awareness campaigns are being done to reduce the prescription and use of antibiotics, mainly to avoid the profilatic use and save antibiotics to be used just when they are really needed. Once disseminated in the human and animal microbiomes and in the environment, there are multiple factors that drive the increase of antibiotic resistance, such as pollution, poor sanitation conditions, or deficient healthcare assistance.
Can the same bacteria be resistant to several antibiotics?
Yes, these are the so-called superbugs that can resist to several antibiotics. This capacity is acquired through the gain of successive resistance pieces, scientifically designated as antibiotic resistance genes. See also the FAQ “What are superbugs?”
Why is it important to take antibiotics exactly as prescribed?
The prescription should be always made based on the identification of the infectious bacteria as well as the antibiotic susceptibility profile. Once this information is available, the dose prescribed should be required to efficiently eliminate the infectious agent. If treatment is halted before the due time, there is the risk that only part of the infectious bacteria was killed and these will multiply making the person sick again. It is possible that bacteria that were not eliminated were those with the highest level of resistance, making the second infection even more difficult to treat. For the same reasons, antibiotic intakes doses should not be skipped.
Very important: antibiotics must always be taken after medical prescription, and based on a microbiological diagnostic to determine the cause of the disease. The wrong medicine will delay the treatment.
What are the main causes of antibiotic resistance?
In addition to the excessive, and not always appropriate, use of antibiotics other causes may be contributing to the increase of antibiotic resistance. For example, 1) in the human body, a poor or unbalanced microbiome will give the antibiotic-resistant bacteria opportunity to proliferate; 2) in food-animal production the use of antibiotics favour the overproliferation of antibiotic-resistant bacteria; 3) in the environment, eutrophic systems with high load of nutrients and pollution will favor the proliferation of antibiotic resistant bacteria.
These three examples show the importance of the One-Health concept on the dissemination of antibiotic resistance, assuming the links on the occurrence of antibiotic resistance in humans, animals, and the environment.
How can antimicrobial resistance be measured/valued?
The method most commonly used to measure the susceptibility of a bacterium to different concentrations of antibiotic in either broth or agar culture media or on paper discs. The lowest antibiotic concentration that inhibits bacterial growth is the minimum inhibitory concentration (MIC).
The application of molecular biology techniques, as quantitative PCR, allows the quantification of genetic determinants related to antibiotic resistance (antibiotic resistance genes).
- Davison, H. C., Woolhouse, M. E., & Low, J. C. (2000). What is antibiotic resistance and how can we measure it?. Trends in microbiology, 8(12), 554-559.
- Manaia, Célia M., Jaqueline Rocha, Nazareno Scaccia, Roberto Marano, Elena Radu, Francesco Biancullo, Francisco Cerqueira et al. "Antibiotic resistance in wastewater treatment plants: tackling the black box." Environment International 115 (2018): 312-324.
What can I do to help prevent antibiotic resistance?
- Take the antibiotics as prescribed.
- Do not skip doses.
- Do not save antibiotics.
- Do not take antibiotics prescribed for someone else.
- Talk with your health care professional.
- All drugs have side effects.
- Take care of environmental sustainability, avoiding the emission of pollutants, contributing to the preservation of natural resources such as soil and water and, protecting biodiversity.
More info can be found here.
Does antibiotic resistance go away?
Resistance does not go away.
Most acquired antibiotic resistance mechanisms are not associated with a fitness cost for the bacteria, meaning that the presence of that resistance type in the bacterial cells does not affect its survival or proliferation rate. The practical implication of this is that once acquired, a resistance type will not be lost, even when the antibiotic is no longer used.
Andersson, D. I., & Hughes, D. (2010). Antibiotic resistance and its cost: is it possible to reverse resistance?. Nature Reviews Microbiology, 8(4), 260-271.