Antibiotic resistance: A threat to human health
Introduction: Antibiotics are produced by microorganisms to
fight against each other. Therefore antibiotics are specialized on harming
bacteria-cells. This is a big advantage for medicine for fighting against bacteria
caused diseases, because antibiotics only attack prokaryotes and no eukaryotes.
To build antibiotic resistance is an important part of evolution and occurs naturally.
But the fact that antibiotic resistance increases in human pathogen bacteria is
concerning. This phenomenon is caused by the inappropriate application of
antibiotics in medicine and cattle breeding. (Kuhn, 2013)
Resistance formation: Every exposure to an antibiotic that
does not kill a bacteria gives it a chance to adapt and build resistance genes.
Therefore the use of too much antibiotics makes it possible to adapt faster and
in a broader range (BAG, 2014). Due to BAG an inappropriate application occurs in
the following cases:
-
Antibiotics
given in case of a viral caused disease (instead of bacteria caused)
-
Underdosing
of antibiotic agent
-
Broad
spectrum antibiotic instead of narrow spectrum antibiotic (causes multidrug resistance)
WHO also
gives the following reasons:
-
Application
of bad quality antibiotics (dose is not appropriate)
-
Application
of low dose antibiotics in animal husbandry to prevent from diseases or to
enhance the growth
Resistance spreading: As described above the development of
antibiotic resistances is a natural evolutionary process and they will be given
further to bacteria’s offspring (WHO, 2014). Bacteria are even able to exchange
genetic information and get some resistance genes from each other (Kuhn, 2013).
Bacteria are omnipresent (skin, soil, ...) and are given easily from human to
human or from animal to human and the other way round (BAG, 2014). Global trade
and travel enhances the spreading additionally (WHO, 2014). But the most
efficient way to spread human and animal health threatening resistant bacteria
in the environment is to bring out excretions products on the fields or let
passing antibiotics through the waste water treatment plants without removing
them. In soil and rivers they will be used by bacteria to build resistances.
(BAG, 2014)
Concerns of antibiotic resistances in soil: Marti et al. investigated in their
study if antibiotic resistant bacteria are more abundant on vegetables grown in
manured soil or in unmanured soil. They found out that there are a lot of
antibiotic resistant bacteria already in the soil without fertilizing it. In my
opinion it’s necessary to know if these naturally occurring bacteria could
cause a disease or not. If not we don’t have to fear eating raw vegetables
cultivated in unmanured soil. But as Marti et al. also say it’s important to be
aware of bacteria ubiquitous on vegetables and the importance of washing and
peeling them properly before eating them raw. In order to reach a better
protection producers should take care about safe production practices (Marti et
al., 2013).
Adequacy of proposed strategies: BAG proposes a strategy that includes
several aspects (monitoring, prevention, appropriate application, research and development,
cooperation, information and education, combating resistances, circumstances).
In my opinion it’s important that not only resistances are fighted but also
sources of resistances and providing information are taken in account. We
should manage the problem by attacking its roots.
________________________________________________________________________
Literature:
BAG (2014). Entwurf Strategie Antibiotikaresistenzen (StAR), Entwurf 8.12.2014. Bern: BAG.
Kuhn, R. (2013). Vorlesungsskript
Mikrobiologie. Wädenswil: zhaw.
Marti, R., et al. (September 2013). Impact of Manure Fertilization on the
Abundance of Antibiotic-Resistant Bacteria and Frequency of Detection of
Antibiotic Resistance Genes in Soil and on Vegetables at Harvest. AEM,
S. 5701-579.
WHO (2014). 10 facts on antimicrobial resistance. Abgerufen am
18.2.2015 von http://www.who.int/features/factfiles/antimicrobial_resistance/facts/en/
WHO (2014). Antimicrobial
resistance. Factsheet N°194. Abgerufen am 18.2.2015 von http://www.who.int/mediacentre/factsheets/fs194/en/
Hi Anna
AntwortenLöschenI am impressed by a good post! Just as a minor point: you might use a little more scientific references, but the current list is also informative.
You exactly hit the nail on the head: resistant bacteria in soil could be the source of novel antibiotic resistances. This is also the reason for a lot of currently ongoing research in the field.
Please continue like this in the next post!
Regards
Theo
Hey Anna
AntwortenLöschenI really think the main problem in the health sector is the use of antibiotics in case of a viral infection. I guess it's not only because physicians do not treat a viral infection correctly. Often patients do not understand the difference between bacterial and viral infection. Because of that they start treating themself by using an antibiotic they have left of another indication, and the building of resistant bacteria occurs. Naturally the other points you mentioned (underdosing and broad spectrum antibiotic) are a problem as well, so it's really the combination of all of them:-)
See you soon.
Dominique
Hey Anna
AntwortenLöschenYou explained very well how antibiotic resistance spreads and why. It is interesting to see that the WHO and the BAG has some slight different meanings or opinions of inappropriate application. This shows that the problem has to be solved in different ways, depending on the country or region.
You mention that the producing side should take care about safe production practices. I think this is a very important part in preventing antibiotic resistance. However this problem has not in each country the same importance. So the strategy to prevent antibiotic resistance has to be different for each country/ region.
Tamara
Hi Anna
AntwortenLöschenThank you for this interesting blog entry. It gives me additional approaches.
I never was thinking about antibiotic resistance when I ate unwashed fruits or vegetables. So thank you for that input. It would be interesting if ingested bacteria do survive when they pass the gastro-intestinal system. Did Marti et al. (2013) write something about that?
Best regards, Sarah