Friday, November 11, 2011

Causes of superbugs prevalence in HAIS

It is notable that the majority of infection control problems in the hospital are due to increasingly resistant bacteria. It is important to reflect on the role that antibiotic use may have as a selecting force for evolution of these superbugs. Selecting force of antibiotics, combined with lapses in infection control techniques make from these resistant organisms resident flora in hospitals and lead to their spread from person to person (Gould, 2009).
A-Selective pressure of antibiotic use:
Current policies to shorten length of stay and curtail costs encourage empiric use, often of unnecessarily broad-spectrum antibiotics. Combination therapy is often used for a number of reasons including broadening spectrum to accommodate increasing antibiotic resistance. This over-use and sometimes misuse inevitably leads to evolution and spread of superbugs (Gould, 2009).
Evolution of antibiotic resistance is the result of two essential forces: variability (chance) and selection (necessity). Variability is created by random mutation; variants with a mutation in the antibiotic target become resistant. These variants are selected by antibiotic use and consequently they increase the frequency of resistance. If the variability (as in a hyper-mutable strain) increased or the intensity of selection (antibiotic hyper-consumption) increased, the result is more resistance (Baquero and Cantón, 2009).
Indeed, antibiotic use not only selects for and maintains antibiotic resistance, but it also enhances its spread. This point is crucial to the control of modern HAIs and illustrates why traditional infection control policies have not been as successful as was hoped (Dancer, 2008).
Antimicrobials are the only category of drugs that have “societal” consequences. In other words, anti-hypertensives or lipid lowering agents only impact the person receiving these drugs. While in case of antimicrobials, in contrast, an individual can receive these drugs, develop resistance to them, and then pass along the newly created resistant organism to individuals that have never been exposed to these antimicrobials (Owens and Lautenbach, 2009).
Certain antibiotic classes are highly associated with colonization with superbugs compared to other antibiotic classes. The risk for colonization increases if broad-spectrum antibiotic is used or if the antibiotic is used in low doses over long periods. In the case of MRSA increased rates of MRSA colonization and infections are seen with glycopeptides, cephalosporins and quinolones therapies (Tacconelli, 2008).

B-Lapses in infection control techniques:
Reliance on antibiotics has become over-reliance, leading to poor quality infection control in the belief that infection has been beaten by antibiotics (Gould, 2007).
Cleaning is routinely monitored by visual assessment. Looking to see if a ward is clean does not provide a reliable assessment of the infection risk for an individual patient on that ward. The organisms that cause infection are invisible to the naked eye and their existence is not necessarily associated with the presence of visual dirt (Dancer, 2009).
The increase in superbugs appears to be linked to hospital cross-infection by these organisms. If staff enters a room containing MRSA patient, two-thirds of them will acquire the patient’s strain on gloved hands or apron (Dancer, 2009).
Poor hand hygiene by hospital staff has been associated with the spread of resistant organisms and an increase in hand washing results in decreased rates of these organisms (Girou et al., 2006).
You want to know more about antibiotics Read
Manual of Antibiotics: Method of Actions, Mechanisms of Resistance and Relations to Health Care associated Infections

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