Prevalence of Escherichia Coli on Money

PREVALENCE OF ESCHERICHIA COLI ON PHILIPPINE PESO BILL WITHIN THE VICINITY OF ILOILO CITY 2012-2013 A Research Paper Presented to The Faculty College of Medical Laboratory Science Department Central Philippine University Iloilo City In Partial Fulfillment of the Requirement for the Research 1 JUSTINE GRACE G. JIMENEA ISAAC JAMES T. LEDESMA MAJA HANNAH LOU L. LOJA ROBERTO R. MANALO JR. JIRAH L. PEDROSA MARCH 2013 CHAPTER 1 INTRODUCTION Background of the Study A classic characteristic of human parasitic and bacterial agents is the evolution of routes for transmission pathogens to susceptible hosts.
The environment plays a critical role in transmission to humans, with many environmental materials serving as vehicles. Microbial contaminants may be transmitted directly, through hand-to-hand contact, or indirectly, via food or other inanimate objects like fomites. (Rote, et al. , 2010) According to Umeh, et al (2007), Contamination of objects by pathogenic microorganism is much a public health concern as contaminated materials can be sources of transmitting pathogens. Items that pass from hand to hand are likely to be contaminated with disease causing microorganisms especially if handled with unclean hands or kept in dirty surroundings.
Ahmed, et al (2010) pointed out that paper currency is widely exchanged for goods and services in most countries worldwide. Paper currencies are widely used and each currency is exchanged many times during the time it circulates. If some of these paper money are contaminated with pathogenic bacteria, there is a potential to spread these microorganism. Pope, et al (2002) mentioned, since bacteria, have been shown to spread from person to person via contact with fomites paper money, therefore, presents a particular risk of public health.

Paper currency is commonly and routinely passed among individuals. Thus bacteria could be spread on the surface of paper currency. Paper currency, as asserted by Oyero, et al (2007) can be contaminated by droplets during coughing, sneezing, touching with previously contaminated hands or other materials and placement on dirty surface. Paper currency is commonly handled by various categories of people during transaction. The possibility that paper currency might act as environmental vehicles for the transmission of potential pathogenic microorganisms was suggested in 1970s.
Various pathogens related with throat infection, pneumonia, tonsillitis, peptic ulcers, urino-genital tract infection, gastroenteritis and lung abscess had been reported. (Pope, et al. , 2002) The money which may get contaminated during production, storage, after production and during use are always in circulation. Numerous research on currency in several countries indicated bacterial contamination. A study in Bangladesh reported thatEscherichia coli (58%),Klebsiella(50%), Staphylococcus aureus(25%), Salmonella (15%), Bacillus (9%), Pseudomonas (7%) and Vibrio cholera (5%) were recovered from Bangladesh Paper Currency Notes (Taka). Ahmed, et al,. 2010) In another study carried out in Nigeria, the bacteria isolated E. coli (80%), Aerobacter (59%), Salmonella (40. 9%), yeast cells (36. 4%), Streptococcus fecalis(31. 8%), Staphylococcus aureus( 27. 3%) and the coagulase negative staphylococci (18. 2%). (Umeh, et al. , 2007) A similar study was also conducted in Nepal and reported thatStaphylococcusaureus, S. Epidermidis, Streptococcus pyogenes, Klebsiella pneumonia, Salmonella choleraesius, E. coli, Enterobacteraerogenesand cloaceaewere isolated from paper money of Nepal. (Lamichhane, et al. 2009) In another study in India, 100% of the currency notes of Indian upee were contaminated with bacteria. Mainly three species including E. coli, Proteus spp. And Staphylococcus aureuswere isolated. (Bhat, et al. , 2010) In another study in India, currency samples of different denominations from different occupational groups were evaluated for isolation of microbial contaminants and Staphylococcus aureu, E. coli, Bacillus spp. , Klebsiella spp. , Proteus mirablisand fungus like Aspergillusnigerand Fusariumwere isolated from these paper currency notes. (Rote, et al. 2010) Although, a lot of studies on the microbiological status of paper currency have been carried out elsewhere, data on the microbial contamination of the Peso (Philippine currency) is scanty. In order to know the prevalence of Escherichia coli on Philippine Peso bill within the vicinity of Iloilo City in the year 2012-2013, this study is to be conducted. General Objectives What is the prevalence rate of E. coli contamination on the Philippine peso bill of Public Utility Jeepney (PUJ)? Specific Objectives 1. ) What is the prevalence rate of E. coli contamination on the 20 peso bill? . ) What is the prevalence rate of E. coli contamination on the 50 peso bill? 3. ) What is the prevalence rate of E. coli contamination on the 100 peso bill? Research Paradigm Independent variableDependent variable Location:Public Utility Jeepney (PUJ)Value:20 PHP50 PHP100 PHP| Prevalence rate of Escherichia coli contamination| Figure 1. Schematic Diagram of the Study Definition of Terms To provide clarity and understanding, the following terms were defined conceptually and operationally. Bacteria- are minute, unicellular organisms that reproduce by binary fission.
They are considered prokaryotes due to the absence of nuclear membrane. They possess both DNA and RNA. They sensitive to penicillins, tetracycline and chloramphenicol. (Moraleta, Review of Microbiology) In the study, the bacteria is the E. coli to be identified. Escherichia coli- or E. coli is a bacterium that is commonly found in the gut of humans and other warm-blooded animals. While most strains are harmless, some can cause severe foodborne disease. E. coli infection is usually transmitted through consumption of contaminated water or food, such as undercooked meat products and raw milk.
Symptoms of disease include abdominal cramps and diarrhoea, which may be bloody. Fever and vomiting may also occur. Most patients recover within 10 days, although in a few cases the disease may become life-threatening. (WHO, 2012) As used in this study,E. coli is the subject of the study and it is isolated in the surfaces different peso bill. Contamination-The act or process of contaminating; pollution; defilement; taint; also, that which contaminates. (http://www. merriam-webster. com/) In this study, contamination refers how high or low E. oli bacteria level is found on the surface of the peso bill. Denomination-a value or size of a series of values or sizes. (http://www. merriam-webster. com/) As used in thisstudy, 20, 50, 100 are used as denomination. Paper bill- (often known as a bill, paper money or simply a note) is a type ofnegotiable instrument known as a promissory note, made by a bank, payable to the bearer on demand. (http://en. wikipedia. org) In this study, paper bill was tested for the presence or absence of E. coli. Philippine peso- is the currency of the Philippines.
The peso is usually denoted by the symbol “? “. Other ways of writing the Philippine peso sign are “PHP”, “PhP”, “Php”, and/or “P”. (http://www. wikipedia. org/) As used in this study, Philippine peso paper bill was tested for the presence of E. coli. Public Utility Jeepney (PUJ)- are the most popular means of public transportation in the Philippines. (http://www. wikipedia. org/) In this study, this is the location of the Philippine peso billwhere the E. coli is to be isolated. Significance of the Study The result of the study will benefit the following:
Department of Health. May provide information on how to properly handle and care for money to prevent the risk of Escherichia coli contamination from hand-to-hand communication. The Medical Researchers. They may use this study as reference for future studies especially in the prevention of the deadly disease caused by Escherichia coli on the circulating money. Commercial Banks. They may have an idea that Escherichia coli can inhabit the paper bill and cause such disease. Hence, they will come up bacteria-free money. Jeepney Drivers.
May help them in protecting their selves from being the courier of contaminated money from one person to another. The public. The result will provide information and awareness about money contaminated by Escherichia coli circulates, and find ways in preventing disease and reduce mortality. Future researcher. The result of the study may also be used by other future researcher as a reference or basis for future researcher or investigation. Scope and Limitation of the Study This study aims to determine the prevalence of Escherichia coli contamination on Philippine peso bill within the vicinity of Iloilo City.
A total of 45 paper currency of denominations, fifteen paper currencies of each: 20 PhP, 50 PhP and 100 PhP in circulation were randomly collected in 15 jeepneys at different times. Coins were excluded from the study. Paper currencies were gathered from Jaro-CPU Public Utility Jeepney (PUJ) from CPU to Iloilo City route and vice versa. This study is conducted during the month of March until May in the year 2013. Persons handling the bill were asked to deposit them in sterile polyethylene bags, sealed and taken to the Medical Laboratory Science Research Laboratory of Central Philippine University, for analysis. CHAPTER 2
REVIEW OF RELATED LITERATURE AND STUDIES This chapter deals with the related literature and studies relevant to the study of Escherichia coli contamination on paper money bills. Money in the form of notes or coins is handled by everyone, and ‘dirty’ money (money contaminated with pathogenic microorganisms) is always in circulation. Contamination may occur during production, during storage after production, and during use. Microorganisms on the skin can be transferred from cashiers, salespeople and the general public to the currency notes that they handle. Contamination from the anal region, wounds, nasal secretions and aerosols enerated by sneezing and coughing are potential sources of transfer of microorganisms to currency notes during handling. Staphylococcus epidermidis, Pseudomonas aeruginosa and Klebsiellaaerogenes have been reported to survive well on the skin,and are known to be transferred from fabrics to hand as well as from hand to fabrics. (Tswana, 2000) Items that are passed from hand to hand are likely to be contaminated with disease-causing bacteria particularly if carried with unclear hands, or kept in a dirty environment. Similarly, paper currency is widely exchanged for goods and services in countries worldwide.
Currency contamination with pathogenic bacteria is of much public health concern as contaminated materials can be sources of serious pathogens. Paper currency, therefore presents a particular risk to public health, since they go in circulation and contaminate the hands of others transmitting pathogenic organisms in the process. (Uneke&Ogbu, 2007) Pathogenic bacteria that may survive on the currency banknotes may serve as a potential source of enteropathogens causing food poisoning because food vendors handle and serve food and at the same time handle currency banknotes as they sell. Cardoenet al. , 2009; Lamichhaneet al. , 2009) The incidence of food poisoning is on the increase worldwide, although it is estimated that only 10% of cases are reported – just the tip of the iceberg. Money bill play a major role in transmission of pathogenic bacteria. Some mathematical models have been developed to help understand the movements of currency and how this might contribute to the global spread of disease. One of the main sources of pathogenic or food-poisoning bacteria is people. People commonly carry these bacteria in their nose, mouth, wounds and intestines, and on their skin.
There are several reports of the occurrence of microorganisms, in particular bacteria, on cash – banknotes and coins. A study in the US showed that only 6% of banknotes tested were free from microbial contamination. Dirty money Modern banknotes are made from a special blend of 75% cotton and 25% linen with small segments of fibre, so ‘paper’ money is something of a misnomer. The ‘paper’ is referred to as the substrate during the manufacturing process; this is an appropriate name as bacteria require a substrate for growth.
The cotton/linen/fibre combinations of banknotes produce a strong bond and do not pull apart, unlike the fibres of ordinary paper. The average life p of a low denomination paper banknote is about 24 months. In the early 1980s, an American Bank developed polyethylene fibres for use as currency and they are still in use in some Central American countries. Non-fibrous, non-porous, polymer banknotes, developed by the Reserve Bank of Australia, were first issued as currency in 1988. The banknotes were made from biaxially oriented polypropylene that made them more durable, with security features that rendered them difficult to counterfeit. Aidoo, 2011) Various routes are known that lead to the contamination of paper bill. Handling of it results in the transfer of bacteria from money onto hands or from hands onto money. Individuals who cough or sneeze into their hands can easily transfer bacteria onto currency when they handle it. Viruses may also be transmitted when infected people touch surfaces, such as banknotes, that are then touched by others. In the hospitality and catering industry, it is unacceptable for staff to use one hand to handle food and the other to handle money.
Food, either cooked or uncooked, may contain bacteria which can be transferred either directly or indirectly through a medium such as a work surface onto currency. This may occur particularly with street food, mobile food vendors and in retail outlets at the counter. Obviously, the transfer of pathogenic bacteria to food that is ready to be eaten and that requires no further heat treatment could have serious consequences. Should money be handled between hand washing and food handling, then it is equally important to repeat the process of hand washing before handling high-risk food.
Wallets, purses, cash registers and other ‘closed’ environments are conducive for microbial growth because they create warm and moist conditions. Transfer of micro-organisms from one banknote to another in such closed environments may also be common. (Aidoo, 2011) Money on which pathogenic microorganisms might survive represents an often overlooked reservoir for enteric disease (Michaels, 2002). In most parts of the developed world, there is a popular belief that the simultaneous handling of food and money contributes to the incidence of food-related public health incidents (Food Science Australia [FSA], 2000).
It goes without saying that bacteria are everywhere in the environment and most of these microbes are harmless to humans. Should germs on money worry us? Surprisingly, studies of bacteria on money are scarce. In 1972 a study in the Journal of the American Medical Association studied bacteria from 200 coins and bills and found harmful germs like fecal bacteria and Staphylococcus aureus on 13 percent of coins and 42 percent of notes. The study concluded: “Money is truly dirty. ” (http://christophreilly. hubpages. com/) Micro-organisms commonly associated with banknotes include Staphylococcus aureus, ? haemolytic Streptococcus, Enterobacter spp. , Acinetobacter spp. , Pseudomonas spp. , Bacillusspp. , Escherichia coli, Salmonella spp. , viruses, yeasts and moulds. Some of these bacteria are pathogenic, while others may cause opportunistic infections. The predominant, recurrent pathogenic bacteria found on banknotes are S. aureus, Bacillus spp. and Escherichia spp. Many members of the Enterobacteriaceae are found in the gut of animals and humans, and their presence in food or on inanimate objects and surfaces is a good indicator of poor hygiene.
Members of the genera Enterobacter, Escherichia and Klebsiella isolated from banknotes may not themselves cause serious illness; however, their isolation from money may indicate the presence of other pathogenic organisms. Escherichia coliis an important member of the faecal coliform group and its presence on banknotes is of public health concern, especially as some strains can of course cause serious illness. Species of the Gram-negative genus Pseudomonas, which can cause serious opportunistic infections, have also been isolated from banknotes.
S. aureus is the predominant bacterium present on the surface of banknotes and it is also a common cause of food poisoning. This organism is indicative of poor standards of hygiene particularly during food handling and/or preparation. Many people in the adult population carry S. aureus on their skin, in their nasal cavity, and in septic cuts, boils and spots. Coagulase-positive S. aureus is readily isolated from banknotes and the toxins it produces may cause toxic shock syndrome. It has also been implicated in pneumonia.
Streptococci are part of the normal microflora in the mouth, skin, intestine and upper respiratory tract of humans. Although many streptococcal species are non-pathogenic, some have been implicated in meningitis and pneumonia. Bacillus spp. are spore-formers and can withstand harsh, adverse conditions, such as drying. Some species, for example Bacillus cereus, cause two types of food poisoning: diarrhoeal (heat-labile toxin) and emetic (heat-stable toxin). (Aidoo, 2011) The surface of ‘paper’ banknotes is not smooth, but irregular, and can harbour many different types of microorganisms.
The two main factors that determine the occurrence of bacteria on currency are (i) the material that the banknotes are made from and (ii) the age of the banknote. Bacteria have enormous capabilities to allow them to survive in adverse conditions. Two of the most important strategies for survival are their ability to adhere to surfaces and the ability to form biofilms (multicellular aggregates). Members of some genera, such as Bacillus, may form spores and can survive attached to banknotes for many years. Formation of a biofilm or a spore is controlled by genetic activity of the bacterium.
Bacterial cells on banknotes are measured by the number of colony-forming units (c. f. u. ) per cm2 of banknote. A banknote may contain up to 106c. f. u. cm–2, whilst a coin may have up to 103c. f. u. cm–2. Studies have shown that polymer-based banknotes often have a relatively low bacterial count compared with the cotton-based ‘paper’ banknotes. This may be due to various physicochemical parameters of polymers. For example, a negatively charged and hydrophilic synthetic polymer would adversely affect bacterial attachment. (Vriesekoop et. al. , 2010) Escherichia coli, also known as E. oli is a Gram-negative, rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms (endotherms). Most E. coli strains are harmless, but some types can cause serious food poisoning in humans, and are occasionally responsible for food contamination. (CDC National Center for Emerging and Zoonotic Infectious Diseases, 2012) The harmless strains are part of the normal flora of the gut, and can benefit their hosts by producing vitamin K2, and by preventing the establishment of pathogenic bacteria within the intestine. (Hudault et al. , 2001).
Fecal–oral transmission is the major route through which pathogenic strains of the bacterium cause disease. Cells are able to survive outside the body for a limited amount of time, which makes them ideal indicator organisms to test environmental samples for fecal contamination. There is, however, a growing body of research that has examined environmentally persistent E. coli which can survive for extended periods outside of the host. (Ishii &Sadowsky, 2008) Escherichia coli (or E. coli) is the most prevalent infecting organism in the family of gram-negative bacteria known as enterobacteriaceae.
E. coli is often referred to as the best or most-studied free-living organism. More than 700 serotypes of E. coli have been identified. The “O” and “H” antigens on the bacteria and their flagella distinguish the different serotypes. Indeed, some E. coli are beneficial, while some cause infections other than gastrointestinal infections, such as urinary tract infections. The E. coli that are responsible for the numerous reports of contaminated foods and beverages are those that produce Shiga toxin, so called because the toxin is virtually identical to that produced by Shigelladysenteria type 1. Eisenstein et al, 2000) Strains of E. coli that causes diarrhea in man • Enteropathogenic E. coli (EPEC) – causes diarrhea, but the molecular mechanisms of colonization and aetiology are different. EPEC lack fimbriae, ST and LT toxins, but they use an adhesin known as intimin to bind host intestinal cells. This virotype has an array of virulence factors that are similar to those found in Shigella, and may possess a shiga toxin. Adherence to the intestinal mucosa causes a rearrangement of actin in the host cell, causing significant deformation. EPEC cells are moderately invasive (i. . they enter host cells) and elicit an inflammatory response. A change in intestinal cell ultrastructure due to “attachment and effacement” is likely the prime cause of diarrhea in those afflicted with EPEC. (University of Wisconsin–Madison Department of Bacteriology, 2007) • Enterotoxigenic E. coli (ETEC) – Enterotoxigenic Escherichia coli, or ETEC, is the name given to a group of E. coli that produce special toxins which stimulate the lining of the intestines causing them to secrete excessive fluid, thus producing diarrhea. (cdc. gov, 2004) • Enteroinvasive E. oli (EIEC) – this infection causes a syndrome that is identical to Shigellosis, with profuse diarrhea and high fever. EIEC are highly invasive, and they utilize adhesin proteins to bind to and enter intestinal cells. They produce no toxins, but severely damage the intestinal wall through mechanical cell destruction. ( Lan et al, 2004). • Enteroaggregative E. coli (EAEC) – is a subgroup of diarrhoeagenic E. coli (DEC) that during the past decade has received increasing attention as a cause of watery diarrhea, which is often persistent. EAEC have been isolated from children and adults worldwide.
As well as sporadic cases, outbreaks of EAEC-caused diarrhea have been described. (sgmjournals. org, 2003) • Diffusely adherent E. coli (DAEC) – may cause disease in immunologically naive or malnourished children. Discrepancies among epidemiological studies could be explained by age-dependent susceptibility to diarrhea or by the use of an inappropriate detection method such as DNA probing. The current prospective case-control study was done to determine the role of DAEC strains as a cause of acute diarrhea in northeastern Brazil, where childhood diarrhea is endemic. ( M. M. Levine. 1990) • Shiga toxin-producing E. oli (STEC) – Some strains of E. coli produce a toxin called Shiga toxin that causes diarrhea and can lead to severe illness. These Shiga toxin-producing E. coli are sometimes called STEC (pronounced “S-TECK). STEC can be spread from cattle and other animals to people through raw or undercooked meat, unpasteurized milk, or through contact with an infected animal. People can also get infected by consuming contaminated water, raw produce or unpasteurized juice or cider. Foods can become contaminated with bacteria from manure in the field or from raw beef or raw beef juices in the kitchen.
People with STEC who do not wash hands well after a bowel movement can spread it to others. (kingcounty. gov, 2005) The genera Escherichia and Salmonella diverged around 102 million years ago, which coincides with the divergence of their hosts: the former being found in mammals and the latter in birds and reptiles. This was followed by a split of the escherichian ancestor into five species (E. albertii, E. coli, E. fergusonii, E. hermannii and E. vulneris. ) The last E. coli ancestor split between 20 and 30 million years ago. ( Lecointre et al. 2007) In 1885, a German pediatrician, Theodor Escherich, first discovered this species isolated from the feces of newborns and called it Bacterium coli commune due to the fact it is found in the colon and early classifications of Prokaryotes placed these in a handful of genera based on their shape and motility (at that time Ernst Haeckel’s classification of Bacteria in the kingdom Monera was in place). Bacterium coli was the type species of the now invalid genus Bacterium when it was revealed that the former type species (“Bacterium triloculare”) was missing.
Following a revision of Bacteria it was reclassified as Bacillus coli by Migula in 1895 and later reclassified in the newly created genus Escherichia, named after its original discoverer. ( Castellani and Chalmers, 2009) The genus belongs in a group of bacteria informally known as “coliforms”, and is a member of the Enterobacteriaceae family (“the enterics”) of the Gammaproteobacteria. (Garrity, 2005) Escherichia coli encompass an enormous population of bacteria that exhibit a very high degree of both genetic and phenotypic diversity. Genome sequencing of a large number of isolates of E. oli and related bacteria shows that a taxonomic reclassification would be desirable. However, this has not been done, largely due to its medical importance and E. coli remains one of the most diverse bacterial species: only 20% of the genome is common to all strains. (Lukjancenko et. al. , 2010) In fact, from the evolutionary point of view, the members of genus Shigella (S. dysenteriae, S. flexneri, S. boydii, S. sonnei) should be classified as E. coli strains, a phenomenon termed taxa in disguise. Similarly, other strains of E. coli (e. g. he K-12 strain commonly used in recombinant DNA work) are sufficiently different that they would merit reclassification. (Lan; Reeves, 2002) A strain is a sub-group within the species that has unique characteristics that distinguish it from other strains. These differences are often detectable only at the molecular level; however, they may result in changes to the physiology or lifecycle of the bacterium. For example, a strain may gain pathogenic capacity, the ability to use a unique carbon source, the ability to take upon a particularecological niche or the ability to resist antimicrobial agents. Different strains of E. oli are often host-specific, making it possible to determine the source of fecal contamination in environmental samples. For example, knowing which E. coli strains are present in a water sample allows researchers to make assumptions about whether the contamination originated from a human, another mammal or a bird. (Feng et. al. , 2002) The bacteria normally adhere to the mucus or the epithelium on the wall of the intestines, and a single strain can last for months or years. E. coli is one of the most studied and best understood organism, but the organism’s role and how it colonizes isn’t very well understood.
Freter’s Nutrient-Niche theory best describes E. coli’s role: The ecological functions of E. coli depend on the nutrient availability within the intestines of the host organism. Since there are so many different nutrients that can be found within the intestines, it is said that they contain a balanced ecosystem because there are so many different nutrient-defined functions where the E. coli colonize. This is dependent on the preferred nutrient for that particular population occupying the niche. E. coli can also be found outside of the body in faecally-contaminated environments such as water or mud. (bioweb. wlax. edu, 2008) The optimal growth of E. coli occurs at 37 degrees Celsius but some laboratory strains can multiply at temperatures of up to 49 degrees C. Growth can be driven by aerobic or anaerobic respiration. (answers. ask. com, 2010) As E. coli is part of the common micro? ora in the large intestine, it is accustomed to a pH of 7-8. As glucose is absorbed in the small intestine, the E. coli would be used to low concentrations. However, as glucose is its energy source, if excess glucose were available for consumption, it would be expected that the E. coli would utilise it and grow at a faster rate.
Salt (NaCl) is absorbed in the colon, so the amount of salt that the E. coli is exposed to depends on how much salt is consumed by the host organism. However, because of the mechanism of osmosis, extremely high levels as well as complete absence of salt could be lethal to E. coli bacteria. (APUA, 2007 How Antibiotics Work – the Mechanism of Action , Alliance for the Prudent Use of Antibiotics,) You get an E. coli infection by coming into contact with the feces of humans or animals. This can happen when you drink water or eat food that has been contaminated by feces. Healthwise, 2011) E. coli infection can cause human illness when E. coli is ingested through various modes of transmission, including through food and water sources, animal-to-human contact, and person-to-person contact. (Clark, 2012) And according to the (Centers for Disease Control and Prevention) CDC, the transmission of these bacteria to humans may occur in the following manner: •Meat, such as beef from cows, may become contaminated when organisms are accidently mixed in with beef, especially when it is ground. Meat contaminated with E. coli does not smell and looks normal.
It is important to thoroughly cook the beef. •Infection may occur after swimming in or drinking water that has been contaminated with E. coli. •Person-to-person contact in families and in child-care and other institutional-care centers are also places where the transmission of the bacteria can occur. However, the CDC also indicates the way E. coli is transmitted may change over time. (medicalcenter. osu. edu, 2006) To help avoid food poisoning and prevent infection, handle food safely. Cook meat well, wash fruits and vegetables before eating or cooking them, and avoid unpasteurized milk and juices.
You can also get the infection by swallowing water in a swimming pool contaminated with human waste. (nlm. nih. gov, 2012) Pathogenic Escherichia coli, or E. coli, is believed to mostly live in the intestines of cattle. Certain serotypes of E. coli have also been found in the intestines of chickens, sheep, and pigs. (Clark, 2012) E. coli in food E. coli can get into meat during processing. If the infected meat is not cooked to 160°F (71°C), the bacteria can survive and infect you when you eat the meat. This is the most common way people become infected with E. coli.
Any food that has been in contact with raw meat can also become infected. Other foods that can be infected with E. coli include: Raw milk or dairy products. Bacteria can spread from a cow’s udders to its milk. Check the labels on dairy products to make sure they contain the word “pasteurized. ” This means the food has been heated to destroy bacteria. Raw fruits and vegetables, such as lettuce, alfalfa sprouts, or unpasteurized apple cider or other unpasteurized juices that have come in contact with infected animal feces. E. coli in water Human or animal feces infected with E. oli sometimes get into lakes, pools, and water supplies. People can become infected when a contaminated city or town water supply has not been properly treated with chlorine or when people accidentally swallow contaminated water while swimming in a lake, pool, or irrigation canal. E. coli from person-to-person contact The bacteria can also spread from one person to another, usually when an infected person does not wash his or her hands well after a bowel movement. E. coli can spread from an infected person’s hands to other people or to objects. Person-to-person transmission of E. oli occurs through a fecal-oral route, and is particularly common among infants and young children due to their unrefined hygienic practices. Person-to-person transmission of E. coli has also been known to occur between infected individuals and their caregivers, and between infected handlers of certain objects. (WebMD, 2010) In a study entitled “Microbial Contamination in 20-Peso Banknotes in Monterrey, Mexico”, the banknotes came from various sources, including banks, toll booths, convenience stores, restaurants, cafeterias, and yogurt stores, among others.
Samples were randomly obtained and banknotes were placed in a sterile polyethylene bag. The bag was sealed and the sample was taken to the laboratory. All currency banknotes were in good physical condition. Each banknote was placed in 5-mL sterile saline for 24 hours. A sterile, cotton-tipped swab was briefly introduced in the saline and the swab was seeded with a portion of the saline homogenized in blood agar plates and incubated for 48 hours at 37°C in aerobic conditions. Plates were then examined for bacterial growth and the colonies underwent Gram stain.
Gram-negative colonies were grown on Eosin methylene blue agar plates and identified with the Crystal Identification System (Becton Dickinson). Gram-positive cocci were grown on azide agar plates and identified by conventional biochemical tests. Identification of yeasts was performed with CHROMagar Candida (Becton Dickinson). Of the 70 currency banknotes on which bacteriological analysis was conducted, 48 (69%) were found to be contaminated with several microbial species (Table 1).
Sixteen species isolates were obtained from the banknotes: 14 bacterial species (four [23%] Gram positive and 10 [63%] Gram negative) and two (13%) yeast species. The most prevalent species observed was Candida kruseii (19 banknotes, 27%) followed by Burkholderiacepacia (nine banknotes, 13%). Of the 70 banknotes included, 22 (31%) showed no growth. Four bills (5. 7%) yielded bacteria considered pathogenic to healthy hosts and the other 44 contaminated bills (63%) yielded bacteria considered potentially pathogenic to hospitalized or immunocompromised hosts.
Additionally, 11 bills showed more than one microbial species. Pope and co-authors analyzed 68 $1 bills collected from a school and a grocery store and found that five (7%) were contaminated with pathogenic bacteria, 59 (87%) were contaminated with opportunistic pathogens, and just four (6%) were free of bacteria (Pope et al. , 2002). Unlike the study by Pope and co-authors, in our study 31% of the banknotes were negative. Our results are similar to a previous publication (Abrams; Waterman, 1972), in which 70% of banknotes were contaminated with bacteria.
Of these banknotes, 60% contained pathogens, including S. aureus, E. coli, and P. aeruginosa. Medical personnel seem to play an important role in contamination of paper currency, since it has been reported that 13% of coins and 42% of currency collected from laboratory personnel were contaminated with S. aureus, E. coli, Klebsiella sp. , and Proteus mirabilis (Abrams; Waterman, 1972). Additionally, the culture of 100 banknotes and 102 coins collected from medical personnel showed that 3% of coins and 11% of banknotes were contaminated with opportunistic pathogens (KhinNwe et al. 1989). In our study, we did not include banknotes collected in any hospital, but banknotes collected near hospital facilities were contaminated with opportunistic pathogens such as B. cepacia and A. baumannii. Uneke and Ogbu assessed the potential of Nigerian currency notes to act as environmental vehicles for the transmission of pathogenic parasites and bacteria. Currency notes obtained from four major cities in Nigeria were evaluated according to standard techniques. Fifty-four (21. 6 percent [95 percent CI: 16. 50-26. 0]) of the first batch of 250 notes, which underwent parasitological analysis, were contaminated with enteric parasites; 133 (53. 2 percent [95 percent CI: 47. 02-59. 39]) of the second batch of 250 notes, which underwent bacteriological analysis, were found to be contaminated with bacteria. Parasites that were isolated from the notes included Ascarislumbricoides (8. 0 percent), Enterobiusvermicularis (6. 8 percent), Trichuristrichiura (2. 8 percent), and Taenia species (4. 0 percent). Bacteria that were isolated were Streptococcus species (21. percent), Staphylococcus species (12. 8 percent), Escherichia coli (13. 2 percent), and Bacillus species (5. 6 percent). Among dirty/mutilated currency notes, parasite contamination and bacterial contamination were both significantly (p ; . 05) more pervasive (30. 6 percent and 73. 8 percent, respectively) than they were among clean and mint currency notes. Lower-denomination notes were more likely to be contaminated than were higher-denomination notes, although the difference was not statistically significant (p ; . 05).
Parasite contamination and bacteria contamination were both most frequent in notes obtained from butchers and beggars. These results suggest that currency notes may be contaminated, especially with bacteria and enteric parasites, and may serve as sources of infection. The possibility that currency notes might act as environmental vehicles for the transmission of potential pathogenic microorganisms was suggested in the 1970s (Abrams; Waterman, 1972). Paper currency is widely exchanged for goods and services in countries worldwide.
It is used for every type of commerce, from buying milk at a local store to trafficking in sex and drugs. All this trade is hard on currency, with lower-denomination notes receiving the most handling because they are exchanged many times (Gadsby, 1998). Although paper currency is made to take abuse (up to 4,000 folds in each direction) in most parts of the world, including in Nigeria (where paper currency is a rugged mix of 75 percent cotton and 25 percentlinen), it lasts less than a few years in circulation (Gadsby, 1998).
The average U. S. dollar, for instance-like most currency notes worldwide-lasts a mere 18 months (Gadsby). Paper currency also provides a large surface area as a breeding ground for pathogens (Podhajny, 2004). Oddly, publications regarding the degree to which paper money is contaminated with bacteria are few and far between, as the authors found when they conducted a Medline search in December 2005 (Abrams; Waterman, 1972; El-Dars; Hassan, 2005; Goktas;Oktay, 1992; Jiang ; Doyle, 1999; Khin et al. 1989; Michaels, 2002; Pope et al. , 2002; Singh et al. , 2002; Xu et al. , 2005). Furthermore, the search found no documented study of the parasitological status of currency notes (as of December 2005). Scientific information on the contamination of money by microbial agents is also lacking in most developing countries in sub-Saharan Africa, including Nigeria. This dearth of information may have contributed to the absence of public health policies or legislation on currency usage, handling, and circulation in many parts of Africa.
Although the studies done in the United States and Australia have had no major impact on policies or legislation on currency handling and circulation in those countries, they have fostered a higher level of public awareness about the potential for currency contamination by microorganisms (Dow Jones News, 1998; FSA, 2000; Michaels; Jiang ; Doyle; Pope et al. ). In the United States, a whole division of the Department of Treasury deals with what is termed “mutilated currency,” and the department Web site boasts many examples of beleaguered, burned, buried, water-damaged money (Siddique, 2003).
Isolation of various bacterial contaminants from the currency notes was performed via standard techniques described previously (Gilchrist, 1993; Singh et al. , 2002). Briefly, a sterile, cotton-tipped swab moistened with sterile physiological saline was used to swab both sides of the currency note. The swabs were directly inoculated on blood agar and MacConkey agar. The pairs of inoculated media were incubated aerobically at 35-37°C for 24 hours and then examined for bacterial growth according to standard protocol described previously (Cheesbrough, 2000).
The authors isolated bacteria by assessing colony characteristics and Gram reaction, and by conducting catalase and coagulase tests; hemolysis, sugar fermentation, and other biochemical tests, including tests for indole production, citrate utilization, and urase activity; triple sugar iron (TSI) agar tests (for glucose, sucrose, and lactose fermentation); gas and hydrogen sulfide production tests; and oxidase tests, according to protocols described previously (Cheesbrough). Bacteria were identified but were not quantified.
Microbial contaminants can be transmitted directly by hand-to-hand contact or indirectly via food or inanimate objects like banknotes and doorknobs or other objects that come into contact with multiple human hands. Banknotes may be contaminated during storage and exchange, with lower-denomination banknotes receiving the most handling and therefore more contamination (Abrams; Waterman, 1972). In general, a greater number of bacteria have been reported on banknotes than on coins. Banknotes are an excellent transport medium for different types of microorganisms because they are commonly passed among individuals.
Thus, handling money may be a route for transmission of infections (Xu et al. , 2005). We analyzed a sample of 70 20peso bills to isolate and identify bacteria or yeast that may be present on the surface of these banknotes. A recent study that included 1,280 banknotes from 10 countries, including Mexico, reported that pathogens could only be isolated after enrichment and their mere presence did not appear to be alarming (Vriesekoop et al. , 2010). The authors discussed that the presence of bacteria on banknotes is influenced by the material used for the banknotes (polymer based vs. otton based) and the age of the banknotes. They stated that the average number of bacteria encountered on the polymer banknotes was approximately 25% of that found on cotton-based banknotes (Vriesekoop et al. , 2010). That study showed a lower percentage of contamination in Mexican banknotes in comparison to banknotes from China, the U. S. , the UK, and the Netherlands, among others. We analyzed only polymer-based banknotes in good condition, but the presence of contamination was detected in most banknotes analyzed without any enrichment procedure.
In that study, the only contaminations detected in Mexican banknotes were E. coli, S. aureus, and a low percentage of Bacillus cereus, which were interpreted as an indicator of poor hygiene, background microorganism, and the ability of spore-forming bacteria to persist on banknotes, respectively. In our study, we detected S. aureus and Bacillus spp. but we did not detect E. coli. It is important to point out that the 10-country study included currencies obtained only from food outlets and for this reason the results from that study and ours cannot strictly be compared. Source: Microbial Contamination in 20-Peso Banknotes in Monterrey, Mexico Rocha-Gamez, Judith; Tejeda-Villarreal, Paula Nelly, QCB; Macias-Cardenas, Patricia; Canizales-Oviedo, Jorge; Garza-Gonzalez, Elvira; et al. Journal of Environmental Health 75. 2 (Sep 2012): 20-3. ) In another study, entitled “Potential for Parasite and Bacterial Transmission by Paper Currency in Nigeria”, Bacteria that were isolated were Streptococcus species (21. 6 percent), Staphylococcus species (12. 8 percent), Escherichia coli (13. 2 percent), and Bacillus species (5. 6 percent).
Among dirty/mutilated currency notes, parasite contamination and bacterial contamination were both significantly (p ; . 05) more pervasive (30. 6 percent and 73. 8 percent, respectively) than they were among clean and mint currency notes. Lower-denomination notes were more likely to be contaminated than were higher-denomination notes, although the difference was not statistically significant (p ; . 05). Personal hygiene to reduce risk of infection is recommended. Microbial contaminants may be transmitted either directly, through hand-to-hand contact, or indirectly, via food or other inanimate objects.
These routes of transmission are of great importance in the health of many populations in developing countries, where the frequency of infection is a general indication of local hygiene and environmental sanitation levels. (Cooper, 1991). Paper currency is widely exchanged for goods and services in countries worldwide. It is used for every type of commerce, from buying milk at a local store to trafficking in sex and drugs. All this trade is hard on currency, with lower-denomination notes receiving the most handling because they are exchanged many times (Gadsby, 1998).
Bacteriological analysis indicated that 133 (53. 2 percent, [95 percent CI: 47. 02-57. 39]) of the second batch of 250 notes were contaminated with bacteria: 37 (52. 9 percent) of the 70 clean notes and 96 (73. 8 percent) of the 130 dirty/mutilated notes. Neither parasite ova nor bacteria were found on the mint notes. Contamination was related to denomination of currency. Contamination with bacteria was most prevalent among the N5 notes (62. 2 percent) and least prevalent among the N500 notes (32. 0 percent). Contamination was also related to the physical condition of the currency.
The dirty/mutilated notes also had the highest prevalence of bacterial contamination (73. 8 percent). Among the clean notes, 52. 9 percent were contaminated with bacteria. Chi-square analysis indicated a statistically significant association between bacterial contamination and currency condition (? ^sup 2^ = 79. 030, df = 2, p;. 05). In the study reported here, a random approach was adopted for currency sampling; whatever money was provided was collected. The implication is that the majority of the people are exposed to dirty notes.
In Nigeria, poor-currency-handling culture is widespread, and there is indiscriminate abuse of currency notes. A great majority of the populace does not carry money in wallets, and squeezing of currency notes is a common occurrence. Women, especially among the unenlightened, often place money underneath their brassieres, while men place theirs in their socks. These activities not only enhance currency contamination but may also increase the risk of infection from contaminated notes. The situation is further compounded by the inability of the Nigerian government to consistently withdraw old, worn-out, and mutilated notes from circulation.
The presence of damaged currency notes and the failure to consistently withdraw them from circulation are common phenomena in many parts of Africa and Asia (Gadsby, 1998; Podhajny, 2004). The persistence of damaged or terribly mutilated notes in active circulation (some so damaged that they can no longer be stuck together) could elevate their contributory role in transmission of some pathogens, thereby constituting potential public health hazard. ( Source: Uneke, C. and Ogbu, O. Potential for parasite and bacteria transmission by paper currency in Nigeria. J Environ Health, 69 (2007) 54–60. (1)) CHAPTER 3
RESEARCH DESIGN AND METHODOLOGY Purpose of the Study The purpose of the study is to determine the prevalence of E. coli contamination on Philippine Peso bill on Public Utility jeepney (PUJ), specifically on: twenty (20), fifty (50), one hundred (100) pesos. Subjects of the study The subject of the study is the fifteen (15) Public Utility Jeepney drivers routing Jaro-CPU and City Proper bound. On each driver, three (3) Philippine Peso bill samples with amounts: 20, 50 and 100 are to be collected. Data Gathering 45 peso bills are to be used as sample and will be collected on the month of March 2013 at around 10:00 – 11:00 in the morning.
The samples will be taken randomly from 15 Public Utility Jeepney (PUJ) of Jaro – Cpu Route. In each jeepney, three(3) different values: 20, 50, and 100 Php are to be taken and tested, so the total number of samples is 45. The samples collected will be placed in a sealable plastic container, so as to preserve the contaminants on the peso bill. The paper bill will be brought immediately to Central Philippine University, particularly at the Medical Laboratory Science Department Research Lab for confirmatory testing of E. coli. Preparation of Laboratory Materials Needed The following are needed to conduct our study: . ) Sterile cotton swab – will be used in obtaining the possible contaminant on the surface of the paper bill. b. )Eosin Methylene Blue Agar – will be used in the confirmatory test for the presence of E. coli The following are the apparatus needed for our study: a. )Petri Dish b. )Alcohol Lamp c. )Oven All of the enumerated materials above will be borrowed from the stockroom of Medical Laboratory Science Department. A letter of permission was given to the stockroom coordinator for authorized use of the materials stated above. Eosin Methylene Blue Agar (EMB) Procedure: 1.
Using a sterile cotton swab, swab on the surface of the peso bill then streak it onto an EMB agar. 2. Incubate plates at 35oC for twenty-four(24) hours. 3. After 24 hours, observe the plate as follows: The colonies developing on EMB agar plates may be divides as: Typical – nucleated with or without metallic sheen Atypical – opaque, pink mucoid, non-nucleated Negative – no growth or clear watery, or clear colonies Interpretation of Data Philippine peso paper bill that will give a negative reaction on the EMB agar plate is considered not contaminated with E. coli and is safe for everyday domestic use.
There will be no growth or clear watery or clear colonies. On the other hand, water sample that yielded a positive result in E. coli analysis is considered to be contaminated with E. coli bacteria and is not safe. There would be a typical nucleated with or without metallic sheen. Central Philippine University Jaro, Iloilo City College of Arts and Sciences __________________ __________________ __________________ __________________ Sir/Madam, We, the 3rd yearBachelor in Medical Laboratory Science students of Central Philippine University who are currently enrolled in the subject Research is conducting a study entitled Prevalence of E. oli in Philippine Peso Bill. This is a requirement for the completion of the subject in Research 1. In line withthis, we are respectfully requesting you to be one of the respondents of our study by exchanging such peso bills: 20, 50 and 100 respectively that has been collected as commuter’s fare. We need this data for the completion of this study. Your positive response to this request is highly appreciated. Thank you and God bless. Respectfully yours, JUSTINE GRACE JIMENEA ISAAC JAMES LEDESMA MAJA HANNAH LOU LOJA ROBERTO MANALO Jr. JIRAH PEDROSA Researchers Noted by: DR. MA. CORAZON PORRAS Research Adviser Bibliography
Abel, Andrew; Bernanke, Ben (2005). “7”. Macroeconomics(5th ed. ). Pearson. pp. 266–269. ISBN 0-201-32789-9. Ahmed, S. U. , S. Parveen, T. Nasreen and B. Feroza, 2010. Evaluation of The Microbial Contamination of Bangladesh Paer Currency Notes (Taka) in Circulation. Advances in Biological Res. , 4 (5):266-271. Aidoo, Kofi (2011). Microbiology Today Answers. ask. com/Health/Diseases/how_does_e_coli_grow, 2010 Bernstein, Peter, A Primer on Money and Banking, and Gold, Wiley, 2008 edition, pp29-39 Bhat, B. , S. Bhat, K. Asawa and A. Agarwal, 2010. An assessment of oral health risk associated with handling of currency notes. Int. J.
Dntal Clinics, 2(3): 14-16. Bioweb. uwlax. edu/bio203/s2008/moder_just/habitat. htm, 2008 Boyle, David (2006). The Little Money Book. The Disinformation Company. pp. 37. ISBN 978-1-932857-26-9. British Royal Mint. Retrieved 2007-09-02. “Legal Tender Guidelines”. Cardoen, S. ,VanHuffel, X. , Berkvens, D. , Quoilin, S. , Ducoffre, G. , Saegerman, C. , Speybroeck, N. , Imberechts, H. , Herman, L. , Ducatelle, R. , and Dierick, K. Evidence-based semi quantitative methodology for prioritization of food borne zoonoses. Food borne Pathog. Dis. , 6 (2009) 1083-1096. (2) CDC National Center for Emerging and Zoonotic Infectious Diseases. Escherichia coli”. Retrieved 2012-10-02. Christophreilly. hubpages. com Castellani (A. ) and Chalmers(A. J. ): Manual of Tropical Medicine, 3rd ed. , Williams Wood and Co. , New York, 2009 Eisenstein, Barry and Zaleznik, Dori, “Enterobacteriiaceae,” in Mandell, Douglas, & Bennett’s Principles and Practice of Infectious Diseases, Fifth Edition, Chap. 206, pp. 2294-2310, 2000 Federal Institute for Risk Assessment. 30 June 2011. “Samen von BockshornkleemithoherWahrscheinlichkeitfur EHEC O104:H4 Ausbruchverantwortlich in English: Fenugreek seeds with high probability for EHEC O104: H4 responsible outbreak” (in German) (PDF).
BundesinstitutfurRisikobewertung (BfR) in English. Retrieved 17 July 2011.. Feng P, Weagant S, Grant, M (2002-09-01). “Enumeration of Escherichia coli and the Coliform Bacteria”. Bacteriological Analytical Manual (8th ed. ). FDA/Center for Food Safety & Applied Nutrition. Retrieved 2007-01-25. Freeman, David. “Change For a Hundred. ” Popular Mechanics, January 1996, pp. 72-73. Garrity, George M, ed. (July 26, 2005) [1984(Williams & Wilkins)]. The Gammaproteobacteria. Bergey’s Manual of Systematic Bacteriology. 2B (2nd ed. ). New York: Springer. pp. 1108.
ISBN 978-0-387-24144-9. British Library no. GBA561951. Geschickter, J. “Making Money. ” National Geographic World, November 2005, pp. 30-33. Goetzmann, William N. ; K. Geert Rouwenhorst (1 August 2005). The Origins of Value: The Financial Innovations that Created Modern Capital Markets. Oxford University Press. p. 94. ISBN 978-0-19-517571-4. “The Mongols adopted the Jin and Song practice of issuing paper money, and the earliest European account of paper money is the detailed description given by Marco Polo, who claimed to have served at the court of the Yuan dynasty rulers. Greco T. H. Money: Understanding and Creating Alternatives to Legal Tender, White River Junction, Vt: Chelsea Green Publishing (2001). ISBN 1-890132-37-3 Headrick , Daniel R. (1 April 2009). Technology: A World History. Oxford University Press. p. 85. ISBN 978-0-19-988759-0. Hudault S, Guignot J, Servin AL (July 2001). “Escherichia coli strains colonizing the gastrointestinal tract protect germ-free mice against Salmonella typhimurium infection”. Gut 49 (1):47-55. doi:10. 1136/gut. 49. 1. 47. PMC 1728375. PMID 11413110. Jmm. sgmjournals. org/content/56/1/4. full, 2003 Kingcounty. ov/healthservices/health/communicable/diseases/ecoli. aspx, 2005 Krugman, Paul ; Wells, Robin, Economics, Worth Publishers, New York (2006) Lamichhane, J. , S. Adhikary, P. Gautam, R. Maharjan and B. Dhakal, 2009. Risk of handling paper currency in circulation chances of potential bacterial transmittance. Nepal J. Sci and Technol. , 10:161-166. Lan R, Reeves PR (September 2002). “Escherichia coli in disguise: molecular origins of Shigella”. Microbes Infect. 4 (11): 1125–32. doi:10. 1016/S1286-4579(02)01637-4. PMID 12361912. Lecointre G, Rachdi L, Darlu P, Denamur E (December 2007). Escherichia coli molecular phylogeny using the incongruence length difference test”. Mol. Biol. Evol. 15 (12): 1685–95. PMID 9866203. Lukjancenko O, Wassenaar TM, Ussery DW (November 2010). “Comparison of 61 sequenced Escherichia coli genomes”. Microb. Ecol. 60 (4): 708–20. doi:10. 1007/s00248-010-9717-3. PMC 2974192. PMID 20623278. Mankiw, N. Gregory (2007). “2”. Macroeconomics (6th ed. ). New York: Worth Publishers. pp. 22–32. ISBN 0-7167-6213-7. Medicalcenter. osu. edu/patientcare/healthcare_services/infectious_diseases/ecoli/Pages/index. aspx on January 26, 2013 Michaels, B. (2002).
Money and serving ready-to-eat food. Food Service Technology, 2(1), 1-3. Mishkin, Frederic S. (2007). The Economics of Money, Banking, and Financial Markets (Alternate Edition). Boston: Addison Wesley. p. 8. ISBN 0-321-42177-9. Moraleta, Nardito (2007). Review of Microbiology page 91 Nlm. nih. gov/medlineplus/ecoliinfections. html Oyero, O. G. and B. O Emikpe, 2007. Preliminary Investigation on the Microbial Contamination of Nigerian Currency. Int. J. Trop. Med, 2(2):29-32 Pope, T. W. , P. T Ender, W. K Woelk, M. A. Koroscil and T. M. Koroscil, 2002. Bacterial contamination of paper currency Southern Med.
J. , 95:14061410. Rocha-Gamez, Judith; Tejeda-Villarreal, Paula Nelly, QCB; Macias-Cardenas, Patricia; Canizales-Oviedo, Jorge; Garza-Gonzalez, Elvira; et al. , Microbial Contamination in 20-Peso Banknotes in Monterrey, Mexico Journal of Environmental Health 75. 2 (Sep 2012): 20-3. Rote, R. B. , N. G Deogade and M. Kawale, 2010. Isolation, characterization and antibiotic sensitivity of organism from Indian currency Asiatic J. Biotechnology Resources, 3:255-260 Taylor, George Rogers (2007). The Transportation Revolution, 1815–1860. New York, Toronto: Rinehart &Co.. ISBN 978-0-87332-101-3. Thompson,