Bacterial transmission - Thesis Example

0. INTRODUCTION Bacterial transmission has been aided by contact with living organisms as well as by non-living. This is with respect to the ability of infectious organisms to flourish on inert surfaces (Ellis, 2006). According to Shrutz (2003) the microbes also thrive in the air below the 500 feet altitude including spores of Bacillus and Clostridium, algae, Micrococcus, Corynebacterium among others. Respiratory bacteria are mainly dispersed in the air through droplets of saliva and mucous produced when one coughs, sneezes, talks or laughs (Shrutz, 2003). According to Rutala et al. (2006), the microbes, which are freely present in the the air, can in most cases be evident on computer keyboards. In this case, their source is likely to be from human contagion. According to Ellis (2006), German researchers evaluated the ability of transmittable organisms to thrive on non-living surfaces. They realized that bacteria that are gram-positive can thrive on dry surfaces for a long time, with the inclusion of vancomycin resistant enterococcus (VRE), methicillin resistant Staphylococcus aureus (MRSA), as well as Streptococcus pyogenes. The study further indicated that bacteria that are gram-negative bacteria thrive longer than the gram-positive ones. Kramer et al. (2006) stated that, a lot of the nosocomial pathogens could survive on surfaces for months. Further, with respect to the hospital environment, nasocomial pathogens are found to mainly infect the contact areas of hands (Ellis, 2006). These act as the medium for cross-transmission. This clearly shows the introduction of a constant transmission source if no standard measures for disinfection are taken. 1.1. Statement of the problem Bacterial infections have been on the rise, and the resistance of various bacterial strains to drugs has posed a serious challenge to many scholars. According to Kramer et al. (2006), inert surfaces have mainly been described as the source of many outbreaks of nosocomial caused diseases. On the same note, Kramer says that controversies have been on the rise regarding the most suitable treatment for the inert surfaces in health centres in order to avert the transmission of nosocomial pathogens in health care centers. Keyboards are remarkably dynamic computer devices and their usages have been entrenched in virtually every corner of service delivery. Be it in hospitals or any other public or private facility, the computer keyboard is being used every day to efficiently make service delivery more effective. Keyboards have been proven by researchers to be suitable fomites for bacteria to growth and thrive (Bergstrom, 2012; Hartman, 2004). This is due to the high level of contact increasing contamination, as well as their environment supporting the growth and development of the microbes. According to Anderson and Palombo (2009), research from Swisburne University technology in Australia showed that keyboards used by many people tend to be more contaminated by bacteria than personal ones. Furthermore, research by the University of Arizona as cited in Miller et al (2010) stated that an average PC has 400 times more bacteria than the average toilet seat. This clearly shows how keyboards used in hospitals require measures to counter the effects of the pathogens via strategic and sustainable 1.1. Background information This survey assessed the presence of nosocomial pathogens and their resistance to drugs. Numerous studies recent past have been initiated with regard to the role played by the healthcare environment in the transmission of diseases (Kramer et al, 2006). A cause behind the transmission has been attributed to the inanimate surfaces that have been clearly described as definitive sources for outbreaks of nosocomial infections (Kramer et al, 2006). According to Rutala et al (2006), Enterococcus species are among the various bacteria that have been proven to be found in the healthcare environment. It has been considered less probable for a patient to contract a Healthcare Associated Infection (HAI) directly from an inanimate surface; though, patients do contract infections by contact directly with healthcare workers (Bergstrom, 2012; Hota, 2004). With pathogens thriving well on computer keyboards, chances for the nurses to carry them on their skin, gloves, overcoats or any other fomite are exceptionally high (Maki et al 1982). This results in the pathogens finding their way to the patients. The critical interest of research in the healthcare environment falls in the cases of antibiotic resistant strains. Further, there are various basic methods or virulence traits common to many pathogens. The commonalities may be termed as the adherence means, conserved machinery through which the secretion of virulence factors such as protein toxins occurs through the surface membranes, iron attainment systems with weight on mammalian pathogens, and finally the ability to resist host immune- mechanisms like the oxidative killing, as well as defensins in both plant and animal pathogens (Michigan State University, n.d., 2010). In terms of antimicrobial resistance bacteria, Glenn et al. (2005) states that despite the efforts to lower the occurrence and spread of antimicrobial-resistant bacteria, the recovery of these pathogens is on the rise. The human vectors within hospital environments aid enhanced transmission of the anti-microbial resistant bacteria among patients. The bacteria contain drug resistant plasmids that are horizontally transmitted among the strains and species of bacteria (Antibiotics, 2010). Resistance to antibiotics can be either intrinsic or acquired. According to antibiotics (2010), a number of bacteria have been established be intrinsically resistant to given antibiotics. These include the Gram-positive bacteria that are much less susceptible to the polymyxins in comparison to the Gram-negative bacteria (Antibiotic, 2010). Miler et al. (2010) concurs that most of these bacteria observed by researchers are mainly present on the skin and mouth, as well as nasal passages. Therefore, the bacteria being observed on the keyboards could have mainly come from the hands of medical attendants in the hospital environment and library staff for the case of the library environment. Poulter (2008) argues that it has been claimed that PC keyboards can hold a larger number of dangerous bacteria than the lavatory seat. Parmeggiani et al. (2010) states that in the US and Europe, nearly 5 percent to 10 percent of patients receiving acute care, during admission in the health delivery centers have obtained at least one infection. This research mainly is trying to ascertain the presence and magnitude of the microbes on the keyboards used among community settings. Much emphasis on this research regards to the fact that keyboards are being used in every corner of the healthcare environment consequently there is a need to ascertain the presence of pathogens, to recommend proper sanitation measures, and establish awareness of this issue. 1.2. Significance of the study The majority of bacteria on keyboards in the healthcare environments are transferrable via wet gloves, or rather poor infection control from healthcare specialists (Fukata et al., 2008). Bacterial transmission can result from tapping on the keys after contact with contaminants such as blood, various secretions, as well as existing sticky substances within the hospital setting (Fukata et al., 2008). According to Rutala et al. (2003), tests done have shown that 95 percent of cultures from keyboards contain microorganisms with the majority being the natural skin flora. The Enterococcus bacterium is normally found in the bowel and is known to be able to survive adverse conditions that other bacterial organisms cannot. Their best conditions to survive are at 60oC and in anaerobic conditions having varying levels of acidity. According to Hartman et al. (2004), Enterococcus species are the most evident on keyboards being used in the healthcare centre setting. 16S rRNA Sequence: Theory and Procedure 16s rRNA is a ribonucleic acid (RNA) involved in the protein production. The process of protein synthesis does vary from generation to generation (Bruggemann, 2005). In this regard, RNA that is essential for the protein production does not have much variation. The differences present take place in predictable sites. It is critical to note that 16s rRNA is like a fingerprint that compares given locations on a 16s rRNA moleculeusing a database of known organismsthat allows the identification of organisms whose 16S rRNA signature is known (Farrar, 2007). If a given RNA sequence does not go with any identified organism, this gives the result that it is something new. According to Schrutz (2011), the gene encoding for the small sub-unit rRNA serves as a tool for the phylogenic analysis and classification of bacteria due to the high degree of conservation and the fundamental function in the living organisms. According to Shah (2010), sequencing of 16S rRNA genes has extensively been utilized in the probing of the species structure with various backgrounds in bacterial communities. Further, 16S rRNA genetic material fragments can in most cases be recovered from shotgun- metagenomic series and utilized for profiling of species (Shah et al., 2010; Farar, 2007). In clear terms, rRNA genes are considered to be more conservative in function and structure when compared with protein-coding genes. Therefore, the genetic diversity measured could not necessarily and sufficiently reflect the physiological diversity of the respective organisms (Fox et al., 1992). The identification of a rather unusual 16S rRNA genetic material sequence is not enough to prove the existence of various bacterial communities in a given population sample (Nubel et al. 1996). Nevertheless, the importance of utilizing it surpasses the limitations entrenched in the concept. 2.3.1. Phylogenic tree According to Baum (2008), a phylogenic tree, or phylogeny, is an illustration, in form of a diagram that shows evolutionary drop lines indicating various organisms, genes or species from a similar ancestor. Further, Dereeper et al. (2008) defines a phylogeny as a free and simple web that is dedicated in the reconstructing and analyzing of phylogenic associations between molecular sequences. Dereeper (2008) states that phylogenic analysis is core numerous biological research areas. The most significant aspects include identifying the homologous sequence, the various alignments, the phylogenic reconstruction as well as the graphical illustration of the contingent tree. A phylogenic tree is highly crucial in explaining the origin of various living organisms. Also, they are acutely crucial in ascertaining changes over time; the top tips represent the present, with the bottom representing the past (Avise, 2006). 2.0. DISCUSSION Microbial diseases arise due to interactions between different hosts and pathogens. According to Kramer et al. (2006), the majority of nosocomial pathogens are able to persist on dry inanimate surfaces for quite long periods of times. Further, studies have shown that low temperatures such as 4oC or even 6oC have in most cases been related to longer diverse bacteria, fungi and viruses persistency. Nevertheless, Venturi and Passos da Silva (2012) state that while there are many pestilence pathogens, there also are numbers of various harmless and useful bacterial species that can colonize as well as inhabit the host without causing disease. Startlingly, there has been minimal research done on the possible contacts between pathogens and inhabitant bacteria (Venturi and Passos da Silva, 2012). Previous researches have shown that resident bacteria are very significant in the existence of developing pathogens. This is through a wide range of mechanisms including cell-cell signaling, metabolic interactions, prevarication of the immune response and a resident-to-pathogen switch (Wilson, 2002). With this in mind, it is highly crucial to note that pathogen-microbe interactions in the host must be seriously considered with regard to disease severity and development. With respect to hospital surfaces, they are often contaminated with nosocomial pathogens. Due to the large number of people frequenting the areas of the library, there are pathogens present there as well (Bures et al. 2000; Kramer et al. 2006). 2.1.1. Enterococcus faecalis: 2001).With respect to nosocomial infections, E. faecalis is listed as the first to third leading cause (Glick, 2005). According to Alouf and Popoff (2006) many of these infections are experienced after abdominal surgeries or a puncture wound. Increased infections by this pathogen correlate with the increased use of intravenous (IV’s) and catheters. E. faecalis is also responsible for urinary tract infections, bacteremia, endocarditis, meningitis and it can be found in wound infections along with many other bacteria (Glick, 2005; Jet et al., 1994). E. faecalis was initially identified as a Strep D bacterium (Streptococcus faecalis) due to its distinguishing Strep D unambiguous cell wall carbohydrate. In 1984, it was later classified as an Enterococcus (Venturi and Passos da Silva, 2012). Enterococcus faecalisis considerate as one of the most resistant microorganisms to antibiotics. It possesses various natural antibiotic resistances, alongside various acquired immunities transferred by R-plasmids from promiscuous bacteria (Venturi and Passos da Silva, 2012). It is also regarded as a carrier of vancomycin resistance for other genera of bacteria (Glick, 2005). Remedies for E. faecalis incorporate a synergistic combination of aminoglycosides and cell wall active antibiotics (MacKenzie et al. 2006). Drug susceptibility testing is a critical procedure with regard to attempts to prevent further antibiotic resistant strains (WHO, 2001). With the development of new, stronger and more specific antibiotics, multi-drug resistance has also been observed in laboratory testing (McArdle et al, 2006). Additionally, to come up with upgraded and viable solutions to the problem of antibiotic resistance, current studies have been initiated looking into inactivating cytolysin toxin (Alouf and Popof, 2006; Cox et al, 2005). The cytolysin toxin ruptures several target membranes and contributes towards the toxic or the lethal rate of the infection (Alouf and Popoff, 2006). Researchers project that by the inactivation of cytolysin, there will be a decline in the quantity of bacterium in circulation, and it will be inactivated without harming many The Beta-Lactams- these acquired their name from their characteristic ring structure (Antibiotics, 2010). They constitute the penicillin, cephalosporin and carbapenem. Their mechanism of working, are by interfering with the synthesis of the bacterial cell wall made of peptidoglycan (Bambeke, 1999). The ?-lactam antibiotics attach to and hinder enzymes necessary for the synthesis the wall (Bambeke, 1999). Aminoglycosides- are from the actinomycetes bacteria of the soil, or the naturally occurring semi synthetic derivatives that constitute; streptomycin, neomycin and gentamycin (Antibiotics, 2010). These derivatives bind to the 30S subunit of the bacterial ribosome resulting to interference with the formation of the initiation complex and causes misreading of the mRNA (Bambeke, 1999). Tetracycline- these are naturally occurring, and are mainly from soil actinomycetes or their various semi synthetic derivatives incorporating chlortetracycline, oxytetracline and doxycycline (Antibiotics, 2010). Their mechanism of work is by binding to the 30S subunit of the bacterial ribosome resulting to hindering the effectual transfer of activated amino acids to the ribosome halting the synthesis of proteins (Bambeke, 1999). Macrolides- these are also products of actinomycetes (soil bacteria) ortheir semi-synthetic derivatives with the erythromycin being a commonly prescribed macrolide (Antibiotics, 2010). They bind to the 50S subunit of the ribosomes and do not exist in the human cells (Bambeke, 1999). Fluoroquinolones- these are substances blocking the action of two bacterial topoisomerases which are enzymes that relieve the coils that form in the DNA during the opening of the helix in the course of the processes replication, transcription or repair Oxazolidinones- these incorporate the linezolid, which is efficient, against a majority of Gram positive bacteria known to acquire resistance to initially acquired antibiotics (Antibiotics, 2010). These drugs have been found to affect chinks on the armour of bacterias, and that have not been exploited before. Linezoid does not affect the eukaryotic ribosomes hence, the occurrence of mRNAs, translation within the cytosol (Antibiotics, 2010). Propionibacterium acnes: Propionibacterium acnes are a commensal, rod shaped bacilliform; Gram-positive found in a number of locations of the human body (skin, urinary tract, mouth) (Bruggemann et al., 2005). The strain is normally associated to with it- implicated role as the predominant cause of common inflammatory skin condition Acne vulgaris (Farrar et al., 2007). A. vulgarisis anaerobic and its optimal growing temperature is 37oC. Micrococcus luteus: Micrococcus species are closely related genera and are mainly regarded to as the harmless saprophytes that inhabit or contaminate the skin, mucosa and sometimes the oropharynx (Bannerman, 2007). Nevertheless, the y can act as opportunistic pathogens for the immune-compromised and are said to be related to various infections like bacteraemia. According to Kocur et al. (2006), M. Spp. has as well been separated from surgical and blood samples in a number of patients suffering from infectious as well as coronary ailments. M. luteus has earlier on been identified as the causal agent when it comes to endocarditis, intracranial abscesses, pneumonia, septic arthritis and meningitis (Bannerman, 2007). Owing to their probable presence in the uncovered skin of face, hands, arms and legs;M. Luteus is naturally occurring and widespread, in medical samples (Bannerman, 2007; Kocur et al. 2006). The PCR technology has been brought about by the explosion of molecular biology and has initiated a new era of microbial analysis (Strommerger et al. 2003). According to Lin and Yang (2008) the PCR technology is a highly crucial technique that provides an analysis that is reliable, sensitive and accurate, and also rises above the long analysis process through convectional culture and minuscule analysis. With regard to Yamamoto (2002), PCR is the most sensitive technique among the existing techniques used in the identification of microbial pathogens in clinical samples. The PCR technique is a highly crucial one whenever specific pathogens, difficult to culture in vitro or entailing a long cultivation phase, are projected to be present in samples (Strommerger et al. 2003). PCR’s diagnostic worth is described to be highly important. The methodological aspects in diagnosis involve a number of important stages such as, the removal of DNA from specimens, the amplification of PCR and amplicon detection. Nubel, Garcia-Pichel and Muyzer (1997) state that, PCR is critical in the probe of the diversity of oxygenated phototrophic microorganisms present in lichens, various cultures and multifarious microbial communities. This demonstration is conducted with the inclusion of a denaturing gradient, gel electrophoresis. Read More