The growing problem of antibiotic resistance
Over the last sixty years, there has been extensive use of antibiotics to treat microbes. However, the treating of the microbes using antibiotics has been counter-measured by the bacteria which have derived mechanisms which make them no longer susceptible to the drugs thus cushioning them against the effects of the drug on them. In clinical settings, the rising levels of antibiotic prescription have been found out to attribute to the rising levels of antibiotic resistance. To cap it all, the antibiotic prescription has been known to cause not only longer hospitalization periods but also morbidity and mortality.
The antibacterial forms crop up at the time of or prior to antimicrobial treatment. To cap it all, the ecology of the microbes are catalyzed to by the many antibacterial that are now possessed by almost every household.
The society at large is faced with not only multi-resistant infectious diseases but also whose treatment is difficult. The problem of antibiotic resistance can be reversed if the return of susceptible commensally flora is motivated. However, though, to see it from that scope there is the need to understand first how they become resistance to the antibiotic treatment.
The mechanism of antibiotic resistance in bacteria
When the term multidrug resistance was coined, it was meant to describe resistant mammalian tumour cells and later strains of Mycobacterium tuberculosis. However, the scope of that term was extended to include any microorganism (be it bacterium, fungus or parasite) that is multidrug resistant.
Multidrug resistance (MDR) is affiliated with the quantity of the antibiotics and their application method. The resistance of bacteria against the various antibacterial is determined by the different resistance on the same DNA molecule or other determinants such as multidrug pumps. Opportunistic diseases, such as enterococci and Acinebacter baumanii, jump into the fray complicating the efforts of medical technologies.
The conquest of MDR is not deterred by the many patients in immunocompromised conditions and in any case, the have bacteria have ‘evolved’ and this is reflected by how they attack just the most susceptible patients. The lack of therapeutic alternatives has also lead to organisms that have been long known in the clinical field becoming health dangers such as resistance of Salmonella typhi to ciprofloxacin. Drug resistance can be fatal like in Central America after deaths occurred after drug resistance cropped up on S. typhi to both ampicilin and chloramphenicol.
Causes of drug resistance
Two factors attribute to drug resistance. The major factor is antibiotics which act as a catalyst for the organisms to proliferate the organisms that possess the resistance gene. Even though the occurrence of bacteria over millennia has enabled them to face inhibitors of their growth by developing resistance genes, it has come as a surprise for them until the appearance of resistance genes in a clinical environment which soberly piped for the dire need of paying attention to the drug’s use and the increase of the resistant genes.
Ways of antibiotic resistance in bacteria
Drug resistance are mostly catalysed by the spread of the resistance gene from one bacterium to another. This happens via several methods. One method involves the spread of the resistance genes between Gram-positive and Gram-negative bacteria via mechanism used by elements such as plasmids and extra-chromosomal (Alberto at al. 2006). Second is transformation and it’s whereby new strains are integrated from the naked DNA that are discharged from dead bacteria. An example of transformation of discharged naked DNA is exhibited in pneumococci and Haemophilus spp. The third method is whereby new resistance genes are introduced to the new bacterial host by bacteriophages by transferring the resistance genes that are affiliated with either chromosomes or the plasmids. The resistance genes move from a DNA to another, for example, from a plasmid to a chromosome. However, that is only facilitated if they occur in smaller DNA pieces called transposon.
It must be understood that evolution, as it occurs in all animal species, is also present in the microbial settings. The microbes have derived mechanisms that enable them to defend themselves against threats that are posed on their existence. This defence mechanism doesn’t spare antibiotics.
Scope of antibiotic use
It is pegged that in USA alone the yearly consumption of antibiotics is about 23X 106 kg. That goes to people and use in agriculture on a half-half basis. In agriculture, around 7X 106 of which is majorly penicillin and tetracycline, are used in food animals as growth boosters while those used for pesticides range about 45X 103 kg. The latter are used in fruit trees in Southern and Western USA. However, of great interest is that the microbes that are aimed by these antibiotics have become resistant to them. An example is Erwina amylovora strains. When these resistant genes are passed to new transposon, they bring forth new microbes that are resistant to drugs.
Causes of antibiotics resistance
The following may be the six main causes of antibiotic resistance in microbes or may play a vital role in making the microbes drug resistant. One cause may be attributed by the uncontrolled purchase of over-the-counter drugs in pharmacies and from the street vendors which in many cases are not prescribed by medical experts. This could lead to cropping of new drug resistance since the treatment may be administered to little or irrelevantly. The second reason may be attributed by wrongful prescription by doctors. As per the story put in the headlines in 1994 by the Newsweek newspaper, it detailed the story of 26-year old “patient impersonator” to four doctors’ offices in Colorado. Surprisingly, all the doctors prescribed an antibiotic. Two more similar stories and results were obtained from Canada Broadcasting Company and another story in Iran, where a “patient impersonator” faked a cold and visited forty doctors. Amazingly, thirty-seven of those doctors prescribed antibiotics despite the fact that they diagnosed the “patient impersonator” with a viral infection. Courtesy of a research carried out by Jean-Christophe Lucet at al. in a journal titled Antibiotic use: knowledge and perceptions in two university hospitals, the group gathered data concerning the factors that were used in antibiotic prescription. The factors were beliefs and perceptions
In clear, precise and concise words, an antibiotic is a mandatory prescription by all doctors as reflected by a cartoon of a doctor’s sign carried out in the New Yorker magazine stating,” Don’t forget to take a handful of our complimentary antibiotics on your way out.”
The third reason is treatment of chronic, single drug leads to multidrug resistance. This conclusion was reached unto after a research was carried out on three-hundred chickens that were reared on a farm outside Boston purposely for this research. When they were chicks age, half were experimented by feeding them feed that was lace with oxytetracycline (Jean-Christophe at al., 2011). On the grouping that got low quantities of oxytetracycline, there was the emergence resistance in the excretion of Escherichia coli. The fact that chronic, single drug leads to multidrug resistance was reflected twelve weeks later after approximately of E. coli was found to be drug resistance to more than two more antibiotics (inclusive of sulphonamides and streptomycin).
The fourth factor is “social effect”. To paraphrase Stuart as he aptly puts it in The 2000 Garrod Lecture, the effects of use of antibiotics use on the effects of the people within that surrounding is overlooked. This was reached unto after it was revealed by a UK-based dermatology group “a statistically significant difference in the frequency of drug substance resistance among the skin flora of people living in the same home as patients taking acne…” (Pg 27)
The fifth factor is the feature of resistance. Some microbes have been found in some cases inactivating the antibiotics rather than destroying it. An example is the aminoglyoside-inactivating enzymes (Levy, 2005). There may be cases where the defensive mechanism used by the microbe entails expelling the drug out of the body and finally by excretion. In such cases, the effect of the drug may be turned to a selective pressure,’ a post treatment stage’ where it has a lot of time to choose resistant organisms.
A sixth factor is the antibacterial. Antibacterial are found in substances such as detergents. Examples of these detergents are benz-alkonium and QACs. These detergents are used by the microbes these detergents for defence such as where the enoyl reductase protein that targets isoniazid that is used in the TB treatment (Courtesy of the research carried out by Garrod Lecture’s laboratory). The recent upsurge of antibacterial products use in households has in turn favoured the defensive mechanisms of microbes. This is reflected by the emergence of drug resistant in a particular that in any case is dissimilar to that in a hospital environment. An example is Staphylococcus aureus.
First, so as to shield susceptible patients from contracting microbes, either in hospital setting or during recuperation at home, the use of antibacterial should be reserved. Second, there should be introduction of new drugs that can prevent the resistant mechanism. This can be reflected by the efforts of Tufts University and Paratek Pharmaceuticals to introduce new tetracycline that withstand the two tetracycline defensive mechanisms. Third, there should be the execution of antibiotics courses that are shorter. Four, the medical personnel should contemplate reprocessing the antibiotics with new introductions of antibiotic drugs in the market.
A non-chemical alternative of turning around the drug resistance would entail the revitalization of the vulnerable strains. This would involve making them substitute resistant strains by motivating their comeback where they have their rates had been lowered. Several ways of accomplishing that would be: reintroducing vulnerable, competitive flora. An example of that is by using probiotics. This has been applied by exclusion colonization and found to block the colonization of Salmonella in chickens.
There is also dire need for educational programmes on surgeons so as to avoid wrongful diagnoses and prescription of antibiotics which in most cases are irrelevant or in a situation where a doctor prescribes a drug,” wider spectrum than required in a well-defined situation” ( Jean-Christophe Lucet at al, pg 939).
Also as Alberto Sandiage at al recommended, a need for,” antibiotic administration following a pre-established order in consecutive patients (mixing) -and a suggestion by Bergstrom- as a strategy to control and prevent resistance by imposing, under broad conditions, greater heterogeneity than does cycling… and antibiotic prescription patterns balancing the use of different antimicrobials should be promoted .” As they argue, that should lessen the selection pressure that assists in the cropping up of the resistance.
In an agricultural and human environment, the drug resistance problem can also be tackled by using bacteriophages instead of antimicrobials. People should also practice ways that impact on fewer commensal floras since the secret to reversing their drug resistance is held by them. An example would be allowing them to build their colonies take the advantage of successfully treating them by taking their advantage when they obliterate the scope of rival resistant strains.
However, for now, the irrelevant prescription and use of antibiotics will continue. Similarly, the thrash of antibiotics resistance will continue to take its toll. This is according to a research study carried out, courtesy of Jean-Christophe at al. During their study, 20% of units declined participation. Nevertheless, among those that participated (numbering 206 physician respondents), the results obtained were as follows: “82% perceived their practice as suboptimal; 86% felt they had insufficient knowledge; but 70% deemed that adhering to the recommendations” (pg 939). Unless surgeons and physicians are put under educational programmes, the prescription and the sale of over-the-counter drugs by pharmacies and by street vendors controlled, and surgeons and physicians vetted: the fight against antibiotic resistance will be a mile wide but an inch deep.
Alberto S. at al.(2006). Journal of Antimicrobial Chemotherapy (2006). impact of diversity of antibiotic use on the development of antimicrobial resistance , 1197-1204.
Jean-Christophe L. at al.(2011). Journal of Antimicrobial Chemotherapy. Antibiotic use: knowledge and perceptions in two university hospitals , 936-940.
Levy, S. (2005). The 2000 Garrod Lecture. In W. David, Frontiers in antimicrobial resistance: a tribute to Stuart B.Levy (p. 570). Washignton,D.C: ASM Press.