Posted at 12.15.2018
The purpose because of this books review was to verify the literature currently available to the general public on the use of a range of disinfectants used in just a microbiology lab in both the open public e. g. medical center laboratories and the private sector e. g. college or university laboratories. This books review was carried out on the effectiveness of disinfectants so that earlier and current knowledge on the use of the disinfectants can be analysed. This can help give an understanding into the subject area and help with the prep and production of the ultimate report predicated on the research being carried through the books review and research study. The main purpose of the research job being conducted was to compare the effectiveness of a number of disinfectants especially Trigene which has been endorsed for use in the microbiology laboratories of the higher Glasgow and Clyde health mother board which of Virkon which is currently used by the microbiology lab at the University or college of the West of Scotland.
The literature analyzed exhibited that the disinfectants used in scientific laboratories and any other area where microorganisms can result in a problem with cross-contamination, should be evaluated for their performance against the number of organisms which might be encountered. It really is an important requirement that the disinfectants getting used are able to inhibit or wipe out the microorganisms quickly and by using the lowest attention available. (Isenberg, 1985)
A review conducted by Kasthjerg et al (2010) which viewed the consequences of a range of disinfectants on the appearance of virulence genes within the bacterium Listeria monocytogenes. This review showed that results on the virulence gene in the bacterium could be linked to the chemicals found in the disinfectant with some creating an inhibition of the gene while some revealed an induction of the gene
A disinfectant is a chemical which is widely used to eradicate a variety of microorganisms that are currently found in the samples received into a laboratory or are used within an educational setting up for the coaching of microbiology to students.
Disinfectants can have any of the following chemicals as their main active component: halogenated tertiary amines, chlorine containing chemical substances, phenols, quaternary ammonium ingredients and peroxygen's. (Tyski et al, 2009) Thus the disinfectants can be split into groups associated with the substance present as the active component and these teams will be talked about later in the report. It's important that certain requirements are fulfilled when classifying a chemical as a disinfectant, included in these are:-
That the chemical substance components of the disinfectant will not have an adverse effect on the health of the user and if any health issue is realised then appropriate action can be taken to remove this risk i. e. use PPE such as gloves or respiratory face mask. (Severs & Lamontagne, 2002)
It. is also important that the disinfectant has the capacity to render inactive or get rid of an array of microorganisms including viruses, bacterias and fungi. (Severs & Lamontagne, 2002)
It is also important a disinfectant does not have an adverse result when used on equipment.
The research conducted by Kim, Ryu & Beuchat, (2007) demonstrated that the potency of certain disinfectants can be diminished when they are in contact with biofilm surfaces. It is currently thought that there is very little amount of resistance to the disinfectants used due to the presence of a number of chemicals considered to own an antimicrobial result in each disinfectant. (Kasthjerg et al, 2010)
Efficiency testing of disinfectants 's been around for approximately 50 - 60 years ago. (Werner, 2007) In more recent years a working group was setup which set Standards which govern the microbial activity screening of chemicals used as antiseptics and disinfectants. (Werner, 2007: Tyski, S. , et al, 2009) The advantages of these specifications has allowed the efficiency studies to be more quantitative and produce lower margin of problem. (Werner, 2007)
This band of disinfectants includes chemical disinfectants that have the chemical peroxygen and includes Virkon which is one of the disinfectants which will be evaluated through the research study being completed. Virkon is available as a powder and is also diluted for use by dissolving it in distilled normal water to give the required concentration. Virkon's method of action is through the blend of the chemicals chlorine, hydrogen peroxide and paraoxymonosulphate. (Alegente, G. , et al, n. d. ) These chemicals function by oxidation of the plasma membranes of microbial organelles. The effects of peroxygen disinfectants was looked into by a study conducted by Quilez et al, (2005) to find what concentration of the disinfectant and time required for the disinfectant to be most effective when working with Cryptosporidium parvum oocysts.
The literature review conducted by Severs & Lamontagne, (2002) indicated that there is only a "moderate risk of discomfort" to the user when the Virkon is in powder form. The Virkon may stimulate coughing, chocking or wheezing if inhaled while organizing the diluted disinfectant. However, when the powder has been diluted into a liquid form it is considered to cause no injury to the user's pores and skin or eyes. (Severs & Lamontagne, 2002)
As the suggested research to be conducted is related to the efficiency of disinfectants then it was important to review current literature which gives a sign of the success on a variety of microorganisms. Through the literature it was shown that Virkon is effective when used as indicated against a wide range of microorganisms including Gram positive and gram negative bacteria, infections, fungi and spore developing bacteria. The analysis conducted by (Severs & Lamontagne 2002) showed that these organisms were inactivated utilizing a 1% solution of Virkon.
A review conducted by Gaparini et al, (1992) revealed that Virkon was effective when used against spores which have been cultivated onto nutrient agar. This study also suggested that the effects of Virkon were quick acting; this could be attributed to the high attentiveness coefficient of the disinfectant.
Group 2 - Halogenated Tertiary Amine
This kind of disinfectant is considered broad variety and biodegradable and is normally found in mixture with detergents. (Health and Safety Professional, 2005). The halogenated Tertiary Amine group of disinfectants includes Trigene on which part of the research project is situated. Trigene can be obtained as a concentrated liquid or as a company diluted liquid. (Trigene Company) Trigene is also available in sachets which have been approved for use on submarines used by the Military in the UK. (Severs & Lamontagne, 2002) The studies of the analysis by Severs & Lamontagne, (2002) showed that much like Virkon the use of Trigene was effective at rendering inactive infections, bacterias and fungi when used in accordance with the manufacturer's instructions.
Health and safeness tests were carried out on Trigene and the results have shown that the disinfectant poses a low risk to the users if accidently inhaled or ingested and there are no known health hazards by using Trigene. (MediChem international)
Quaternary ammonium compounds
This group of disinfectants is known as to work against most bacterias strains; however they are ineffective against viruses, bacterias which form spores and Mycobacterium. It is likely that this wouldn't normally be a competent disinfectant to be used within a professional medical or college or university microbiology laboratory because of the risk of getting samples including spore forming bacteria, Mycobacterium kinds. The disinfectant can become inactivated by a low PH or the presence of organic material. (Health insurance and Safety Professional, 2005) The method of action for members of this group of disinfectants is that they ruin the cell membrane that will cause cell leakage. (Ioannou et al, 2007) This study also showed an increase in heat range increased the time taken to get rid of the bacterium.
The study done by, Kim, Ryu & Beuchat, (2007) proved that the efficiency of the disinfectant could be linked to the chemical structure of the Benzylalkonmium chloride's hydrophobic alkyl string. It also confirmed that the presence of organic material (infant solution) can reduce the efficiency of the disinfectant.
Hypochlorite and other chlorine-releasing agents
This is a disinfectant which contains chlorine as its active component, and an example of this disinfectant is Milton which happens to be used to sterilise baby items. It is considered a broad spectrum disinfectant as it could inactivate or eliminate a range of bacterias and infections. However, it is known as less effective against bacterial spores. As with the quaternary ammonium materials this group of disinfectants has been shown to be inactivated by organic and natural material and should be prepared daily, this is due to the instability of the chemicals caused by attentiveness and temperatures of which the disinfectant is stored. (Health insurance and Safety Professional, 2005) The hypochlorite disinfectant is provided in the form of Sodium Hypochlorite which is commonly used within the clinical laboratory especially for the cleaning of equipment when advised by the manufacture.
This group includes the disinfectant Hibetine which happens to be used at the University or college of Glasgow and the effective chemical substance is phenol. It has been shown to be a broad spectrum disinfectant which is effective against certain bacterias including Mycobacterium tuberculosis plus some trojans, although shows no action against bacterial spores. The disinfectant is employed with a blend of the phenolic chemical substance and a detergent. The advantages of using this disinfectant is that it's considered steady in undiluted form and organic material will not appear to have the same negative effect on the efficiency of the disinfectant as has been observed in other disinfectants. .
Microorganisms' an introduction
The main reason for conducting the research project was to observe the efficiency of disinfectants when used against a range of microorganisms. The microorganisms to be looked into add a Gram positive bacterias such as Staphylococcus aureus, a Gram negative bacteria such as Escherichia coli, a spore developing bacteria such as Bacillus cereus and a candida e. g. Saccharomyces cerevisiae. The study conducted by Tyski, S. , et al, (2009) used microorganisms that could easily be isolated from nursing homes.
The study carried out by Ioannou et al, (2007) shows that a feature of bacteria especially staphylococcus aureus can get a plasmid which has genes which will allow the bacteria to become immune to certain antimicrobials.
The literature search completed revealed that the microorganisms which are generally used in research showing the efficiency of disinfectants are commonly isolated from medical center patient samples. (Gasparini, et al, 1992)
Gram negative bacteria
Gram positive bacteria
The use of disinfectants in combating the spread of microbe infections from bacterial spores from organisms such as C. parvum, Bacillus anthraxis, Clostridium difficile and bacillus cereus is important as they are the most challenging of most microorganisms to eliminate. (Quilez et al, 2005)
The literature researched has shown that disinfectants are an important part of the working environment of your laboratory as it is vital that the disinfectant has the capacity to inactivate or kill a variety of microorganisms.
The analysis by (Severs & Lamontagne, 2002) proved that both Virkon and Trigene could be classed as reliable and broad range disinfectants as they both killed a variety of microorganisms which range from viruses (both enveloped and non-enveloped) to fungi and bacterias including spore forming varieties.
The analysis by Kasthjerg et al, (2010) deduced that the disinfectants which covered the peroxygen and chloride materials reduced the virulence gene manifestation; however, the disinfectants comprising the quaternary ammonium ingredients encouraged the expression of the virulence gene.
The review conducted by Severs and Lamontagne, (2002) advised that Both Virkon and Trigene were effective at eliminating the bacterias that could poses a health risk to divers but they felt that as the Virkon product possessed managed to eradicate more bacterial and viral strains than Trigene and these effects were produced quicker with Virkon therefore the conclusion was that product (Virkon) is highly recommended a much better disinfectant and be advised for use by divers.