Introduction. MRSA. Methicillin- resistant Staphylococcus aureus (MRSA) is a type of staph bacteria responsible for several difficult- to- treat infections in humans. It is also called oxacillin- resistant Staphylococcus aureus (ORSA). MRSA is any strain of Staphylococcus aureus that has developed, through the process of natural selection, resistance to a number of widely used antibiotics, which include the penicillins (methicillin, dicloxacillin, nafcillin, oxacillin, etc.) and the cephalosporins; this resistance does make MRSA infection more difficult to treat with standard types of antibiotics and thus more dangerous. Bacteria (singular: bacterium) constitute a large domain of prokaryoticmicroorganisms (single- celled organisms) and they are the simplest of creatures that are considered alive. The bacteria are contained in a cell wall, have both types of nucleic acids (DNA and RNA) with an asexual reproduction: multiplication by binary fission. All bacteria have common elements: cell wall, cytoplasmic membrane, cytoplasm, ribosomes and nucleoid. Other elements can be optional: glycocalyx, flagellum, fimbriae or pili, capsule, spores and plasmids. Bacteria are classified according to their affinity or not to Gram stain, morphology and use or non- use of oxygen in their metabolism (aerobic or anaerobic). The Gram stain defines bacteria based on the structural characteristics of their cell walls. The thick layers of peptidoglycan in the "Gram- positive" cell wall stain purple, while the thin "Gram- negative" cell wall appears pink. Bacteria display a wide diversity of shapes and sizes, called morphologies. Bacterial cells are typically 0.5 5.0 micrometres in length. However, a few species are up to half a millimetre long and are visible to the unaided eye. Most bacterial species are either spherical, called cocci (sing. coccus)or rod- shaped, called bacilli. Some bacteria, called vibrio, are shaped like slightly curved rods or comma- shaped; others can be spiral- shaped, called spirilla, or tightly coiled, called spirochaetes. A small number of species even have tetrahedral or cuboidal shapes. More recently, bacteria were discovered deep under Earth's crust that grows as branching filamentous types with a star- shaped cross- section. Page ~ 1 ~
Combining Gram staining, morphology and the use or not of oxygen, the following classification scheme is stable: Aerobic bacteria and facultative anaerobic bacteria. Gram + Morphologies Gram - Morphologies Streptococcus arranged in Neisserias pairs or chain. Acinetobacter Moraxella Staphylococcus cocci in cluster Enterobacter sp. Pseudomonas sp. sporulated bacillus Vibrio Comma's form Corinebacterium Helicobaceter Campilobacter Spiral Spiral Strict anaerobic bacteria Gram + Morphologies Gram - Morphologies Peptostreptococci cocci chain Veillonela Coccus Peptococcus cocci in cluster Bacteroides Clostridium sporulated bacillus Fusubacterium Tapered Actonomyces Bacteria with no Gram strain Mycoplasmas (no wall) Mycobacterium (Tuberculosis and Leprae) Espirilos (TreponemaPalidum) Chamideas (Pneumoninae and Trachomatis) Page ~ 2 ~
MRSA: Domain: Bacteria; Kingdom: Eubacteria; Phylum: Firmicutes; Class: Bacilli; Order: Bacillales; Family: Staphylococcaceae; Genus: Staphylococcus; Species: S. aureus. MRSA is a facultative anaerobic Gram- positive coccal bacterium (0.7-1.2 µm) usually in clusters, non motile, non spore forming. MRSA is frequently found in the human respiratory tract and on the skin, is an extracellular pathogen, causes acute illnesses and produces purulent (pus- filled) lesions. MRSA is transmitted by skin- to- skin contact,it can withstand heat at 60 C for 30 min. Usual reservoirs for MRSA in hospital and institutions are staff, patients, and inanimate objects such as beds, linen, and utensils. By far, the most important reservoir is patients who may be colonized with MRSA without evidence of infection In the general community, most MRSA infections are skin infections that may appear as pustules or boils that often are red, swollen, painful, or have pus or other drainage. These skin infections commonly occur at sites of visible skin trauma, such as cuts and abrasions, and areas of the body covered by hair. In healthcare settings, such a hospital or nursing home, MRSA can cause severe and potentially life- threatening infections, such as bloodstream infections, surgical site infections, or pneumonia. Micrograph of Methicillin- Resistant Staphylococcus aureus (MRSA) Scanning electron micrograph of methicillin- resistant Staphylococcus aureus (yellow) and a dead human neutrophil. Page ~ 3 ~
Introduction. DF (Decon Formula) A non- toxic, non- corrosive, biodegradable aqueous based decontaminant formulation (DF) with enhanced physical stability for the rapid mitigationand decontamination of chemical and biological warfare (CBW) agents and toxic hazardousmaterials has been developed at Sandia National Laboratories. The formulation allows decontamination of areas populated with both people and sensitive equipment; works on all currently anticipated material surfaces and can be incorporated into a wide variety of carriers (foams, gels, fogs, aerosols) that satisfy a wide variety of operational objectives. The basic chemistry of the formula is a combination of two basic active ingredients; quaternary amines and hydrogen peroxide. The formula also contains several stabilizing compounds, which help to extend the shelf life of the formula and control the chemical reaction so that the decontamination occurs in a safe manner. Additional tests indicate that the formulation is effective as a decontaminant on several variety of hazardous bacteria, viruses as wellas materials such as hydrocarbon based compounds. Formulation mechanisms of action: Physically denatures biological agent via a surfactant boring holes in their protein armor Oxidizing agents attack the genetic material (DNA). Hydrolyzing agents attack vital biological agent contents and functions manufactures and commercializes Sandia National Laboratories Decon Formula under Patent License No. 13- C02621. EPA (US Environmental Protection Agency) registered product as Antibacterial, Cleaner, Mildewstat, Decontaminant, Disinfectant, Deodorizer, Fungicide, Algaecide, and Virucide (Including Norovirus and H1N1). DF- 200/ DF- 500ANTIBACTERIAL ACTIVITY The disinfection mechanism of DF against bacteria is most likely a result of the dual synergy between the surfactant oxidizing properties, in addition to these chemistries, peracetate is also produced and further acts as a strong oxidizer. Surfactant or quaternary ammonium compounds (QAC) are compounds comprised of hydrophilic and lipophilic portion. Quaternary ammonium compounds penetrate membranes of microorganisms thanks to the carbon chains (hydrophobic). Through the cationic nitrogen (hydrophilic) phosphates interact with phospholipids, causing the output to the outside of the cytoplasmic vital material. Quaternary ammonium compounds also inhibit the respiratory chain and inactivate cellular enzymes essential for bacterial growth. Page ~ 4 ~
Hydrogen peroxide generates free hydroxyl radicals that can break DNA and RNA structures, attack membrane lipids, and produce disruption in essential cellular components. DF has been demonstrated to provide disinfection efficacy against a broad range of bacteria: - Staphylococcus aureus. - Methicillin- Resistant Staphylococcus aureus (MRSA). - Vancomycin- resistant Staphylococcus aureus (VISA). - Staphylococcus epidermidis. - Salmonella enterica. - Salmonella choleraesuis - Pseudomonasaeruginosa. - Klebsiellapneumoniae. - Proteusmirabilis. - Vancomycin- ResistantEnterococcusfaecalis. - Enterobacteraerogenes. - Escherichiacoli (0157:H7). - Escherichiacoli (ESBL). - Listeria monocytogenes. - Clostridiumdifficile. - subtillis. - anthracis ANR- 1. - anthracis AMES- RIID. - YesinaPestis. The formulation demonstrated efficacy as disinfectant against Methicillin- Resistant Staphylococcus aureus (MRSA) after 10 minutes. Anytime after, samples did not show bacterial growth. Results obtained in studies to evaluate the effectiveness to disinfectof the DF as a Laundry Additive- Disinfectant against bacteria like Pseudomonas aeruginosa, demonstrated no growth in any samples and no growth in the wash water following 25 minutes exposure period around 49⁰C, can be applied broadly to other bacteria like MRSA. References. 1. EPA (US Environmental Protection Agency) Registration: #80346-1/2 2. Agricultural Pathogen Decontamination Technology. Reducing the treat of infectious agent spread. SAND2006-0182. SANDIA REPORT. (October 2005). 3. Final Study Report. ATS LABS. AOAC Germinal Spray Method, Test Organisms: Staphylococcus aureus MRSA, Staphylococcus aureus VISA, Staphylococcus epidermis, Enterobacter faecalis Vancomycin Resistant. (March 24, 2005). 4. Final Study Report #1752. IIT Research Institute. Investigating the microbicidal testing of DF- 200. (March 6, 2002). 5. US Patent. Formulation for neutralization of chemical and Biological Toxants. Sandia National Laboratories (2003). Page ~ 5 ~