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Advances in Biological Research 4 (5): 266-271, 2010
ISSN 1992-0067
© IDOSI Publications, 2010
Corresponding Author: Sahana Parveen Institute of Food Science and Technology (IFST),
Bangladesh Council of Scientific and Industrial Research (BCSIR),
Dr Qudrat-i-Khuda Road, Dhanmondi, Dhaka-1205,Bangladesh, E mail:sahana66@gmail.com
266
Evaluation of the Microbial Contamination of Bangladesh
Paper Currency Notes (Taka) in Circulation
Md. Shakir Uddin Ahmed, Sahana Parveen, Tania Nasreen and Badrunessa Feroza
Institute of Food Science and Technology (IFST),
Bangladesh Council of Scientific and Industrial Research (BCSIR)
Abstract: Bangladesh paper currency, Taka, the legal tender of Bangladesh were surveyed for microbial
contaminations. This study was carried out on hundred paper currency notes belong to all- the notes
denominations obtained from different chosen occupational groups in Dhaka City, Bangladesh. Identification
and characterization revealed active participation of the following species of organisms in the ascending order
of percentage as Escherichia coli 58%, Klebsiella 50%, Staphylococcus aureus 25 %, Salmonella 15 %,,
Bacillus 9%. Pseudomonas. 7% and 'Vibrio cholerae 5%. One hundred and sixty nine bacterial isolates were
recovered belonging to these selected seven species. Currency notes collected from fish sellers, meat sellers,
vegetable sellers, food vendors, office workers, students, bus conductors, beggars and shop keepers with
42.85% - 85.71% Escherichia coli, 28.57% - 92.85%, Klebsiella, 9.09% - 53.84% Staphylococcus aureus,,
0% - 42.85% Salmonella sp,0% - 28.57% Vibrio cholerae, 0% - 25% Bacillus sp and, 0% - 28.57% Pseudomonas
sp. respectively. The study suggested that Bangladesh paper currency is commonly contaminated with
pathogenic microorganisms and this contamination may play a significant role in the transmission of potentially
harmful microorganisms or different diseases such as cholera, diarrhea, skin infections and also poses antibiotic
resistant, so great care should be taken during handling of money and the preparation and handling of food
to avoid cross contamination.
Key words:Bangladesh paper currency % Contamination % Escherichia coli % Pathogenic microorganisms
% Enteric microorganisms
INTRODUCTION Bacteria have been shown to be spread from person to
Paper currency is widely exchanged for goods commonly and routinely passed among individuals.
and services in most countries worldwide. Paper Thus, bacteria could be spread on the surface of paper
currencies are widely used and each currency is currency [2].
exchanged many times during the time it circulates. If Paper Currency, can be contaminated by droplets
some of these papers money are contaminated with during coughing, sneezing, touching with previously
pathogenic bacteria, there is potential to spread these contaminated hands or other materials and placement on
microorganisms. Entering the antibiotic era, it was dirty surface. Paper currency is commonly handled by
anticipated that morbidity and mortality from various categories of people during transaction [3].
infectious diseases would continue to decrease over Contamination of objects by pathogenic microorganisms
time. However, the death rate from infectious is of much public health concern as contaminated
diseases increased by 58% from 1980 to 1992, making materials can be sources of transmitting pathogens. Paper
it the third leading cause of death by 1992 [1]. There money, therefore presents a particular risk to public
is also significant morbidity from infectious disease. health, since communicable diseases can spread through
Furthermore, with the emergence of drug-resistant contact with fomites [2, 4 - 8]. Although paper money is
pathogens, many infections have become more difficult to impregnated with disinfectants to inhibit microorganisms,
treat. Since communicable diseases can spread through pathogens are isolated from paper currency notes and
contact with fomites, paper currency could play a role. coins [9].
person via contact with fomites. Paper currency is
Advan. Biol. Res., 4 (5): 266-271, 2010
267
Various pathogenic microbes associated with MATERIALS AND METHODS
tuberculosis, meningitis, pneumonia, tonsillitis, peptic
ulcers, genital tract infections, gastroenteritis, throat Paper Currency Notes: One Hundred samples of all the
infections and lung abscesses had been identified in available denominations in Bangladesh were obtained
damaged or soiled notes held together with bits from artisans and non-artisans in Dhaka. Artisan groups
of sticky tapes. A study in Egypt reported that 65% were meat sellers, fish sellers, vegetable sellers, food
of the paper bills had bacteria like staphylococcus vendors and Non artisan groups were office workers,
albus, staphylococcus aureus and klebsiella students, bus conductors and beggars. While newly
pneumoniae [10]. minted ones were obtained from a commercial bank were
Studies in different parts of the world have reported used as control. The currencies were observed to have
high rates of microbial contamination of currency notes in been in circulation for about four to eight years
circulation [2, 4, 6, 9 - 16]. The microorganisms implicated (2002 - 2009). The paper currency notes are graded using
included members of the family Enterobacteriacea, condition, appearance and degree of dirtiness as new,
Mycobacterium tuberculosis, Vibrio cholerae, Bacillus moderate and torn as shown in Table 1.
species, Staphylococcus sp., Micrococcus sp. and
Corynebacterium sp. Most likely contaminants of paper Sample Collection: A total of hundred paper money were
money are environmental organisms such as Gram- randomly collected from persons in each category of
positive flora (especially Bacillus sp.) and those arising sampling. To collect the paper money, the individual was
from human normal skin flora such as Staphylococcus requested to drop paper money into a sterile plastic
aureus [6]. packet. The packet was promptly sealed and the
Microbial contamination of paper money is not only individual was given a replacement paper money. The
confined to developing nations. Several studies from the packets were immediately transported to the laboratory for
United States reported contamination of coins and paper analysis.
bills and the identification reveled the presence of
pathogenic microbes like staphylococcus aureus, E. coli, Qualitative Bacterial Analysis: Each paper currency
klebsiella enterobacter [14,15]. Another survey isolated was placed in 100 ml of sterile nutrient broth and
total of 93 different types of bacteria belonging to the incubated for 6-8 hours at 37°C. Thereafter the broth
species staphylococcus, Streptococcus, Enterobacter, cultures were plated on selective and/or differential
Acinetobacter, Pseudomonas, Bacillus, Diptheroids, media, namely Lactose broth, peptone water, Nutrient
Klebseilla pneumoniae and E. vuluneris [2]. However, agar, Eosin Methylene Blue Agar, xylose lysine
there is a dearth of information on the probable microbes deoxycholate agar, blood agar, mannitol salt agar,
associated with the Bangladeshi currency. The aim of this MacConkey agar, TCBS agar, Salmonella Shigella agar,
study was to investigate the likelihood of microbial Cetrimide agar, Baird parker agar, Bismuth sulfite agar.
contamination of Bangladesh paper currency notes. The plates were incubated at 35°C - 37°C overnight.
Knowledge of the microbial diversity of currency notes in Bacterial colonies in each medium were then characterized
circulation can provide the basis for raise health on the basis of colonial, cellular morphology, staining and
consciousness in people during currency handling and biochemical characteristics using standard microbiological
effective control of infection transmission. technique [17].
Table 1: Physical condition of paper currency of Bangladesh collected from different occupational groups
Denomination New Moderate Old Torn Total
BDT 1 2 3 4 6 15
BDT 2 4 5 8 8 25
BDT 5 3 4 3 2 12
BDT 10 5 8 7 4 24
BDT 20 2 2 2 1 7
BDT 50 3 2 1 1 7
BDT 100 2 2 2 1 7
BDT 500 1 1 1 - 3
Total 22 27 28 23 100
BDT = Bangladesh Taka
Advan. Biol. Res., 4 (5): 266-271, 2010
268
RESULTS AND DISCUSSION The study was in accordance with Umeh et al., [18]
The present study revealed the extent and the Nigerian paper currency were Escherichia coli (80%),
level of contamination of Bangladesh paper money Aerobacter (59%), Salmonella (40.1o), yeast cells (36.4%),
with pathogenic microorganisms. The cultures from the Streptococcus faecalis (31.8%), Staphylococcus aureus
collected Bangladesh paper currency yielded one hundred (27.3%), coagulase-negative staphylococci (18.2 %),
and ninety one isolates representing selected 7 different Streptococcus faecalis (31.8%), Aerobacter (59%),
types of bacterial species. Identification showed the Salmonella (40.1%) and yeast cells (36.4%). They also
active participation of these seven species in descending found that 73.4% of old and tattered notes had a high
order of percentage as Escherichia coli 72%, Klebsiella level of contamination, whereas only 42.9% of new notes
50%, Staphylococcus aureus 25%, Salmonella 15%, had a high level of contamination. Thus, the level of
Bacillus 9%, Pseudomonas 7% and Vibrio cholerae 5%. contamination differed significantly between old notes
Table 2 shows the prevalence of pathogenic and newer notes.
microorganisms isolated from the Bangladesh paper Table 3 showes the level of contamination of notes
currency notes from BDT 1 to BDT 500 from different with pathogenic microorganisms collected from artisans
occupational groups mainly artisans and non artisans like fish seller, meat seller, vegetable seller food vendors
groups. The results showed in table 2 indicated that all and shop keepers. The level of contaminants recovered
the currency denominations groups had microbial from currencies obtained from the artisan group was in
contamination and BDT 500, BDT 100 and BDT 50 had descending order of percentage as from the fish seller,
less contamination than other denomination like BDT 1, meat seller, vegetable seller, food vendors and store
BDT 2, BDT 5, BDT 10 and BDT 20. These lower keepers. Taka notes collected from fish sellers, meat
denominations paper money are used frequently for sellers, vegetable sellers, food vendors and shop keepers
different normal daily activities. Higher denominations are were contaminated with E. coli at the rate of 69.23, 69.23,
not used as frequently as lower denominators. Smaller 63.63, 50.0 and 50.0 %; with Klebsiella species at the rate
unit notes appeared to be more highly contaminated than of 92.85, 61.54, 54.54, 33.33 and 50.0%; with Salmonella
larger unit notes such as BDT 500 notes, probably species at the rate of 42.85, 38.46, 18.18, 0.0 and 0.0%; with
because the smaller unit notes such as BDT 1, BDT 2, Staphylococcus aureus at the rate of 7.14, 53.84, 9.09,
BDT 5 and BDT 10 are most frequently handled in petty, 16.67 and 33.33%; with Bacillus species at the rate of
daily monetary transactions. These lower denomination 7.14,7.69, 0, 16.67 and 0.0%; with Pseudomonas species at
money are often tattered and dirty. Old, tattered and dirty the rate of 28.57, 7.69,9. 09, 8.33 and 0.0%; with Vibrio
notes were more contaminated than new notes and thus cholerae at the rate of 28.57, 7.69, 0.0, 0.0 and 0.0%
supports the finding that damaged or soiled notes, respectively. The highest level of contaminants were
especially those held together with bits of sticky tape are recovered from currencies obtained from the fish sellers
particularly dangerous [12]. and meat sellers as compared with others.
who showed that the microorganisms isolated from
Table 2: Percentage occurrence of microorganisms per denomination of Bangladesh paper currency from different occupational groups (total sample =100)
Denomination E. coli% Klebsiella species% Staphylococcus aureus% Salmonella species% Bacillus species% Pseudomonas species% Vibrio cholera%
BDT 1(n=15) 53.33 66.67 33.33 6.67 6.67 6.67 0
BDT 2(n=25) 64 52 28 12 12 8 4
BDT 5(n=12) 50 33.33 16.67 8.33 0 0 0
BDT 10(n=24) 70.83 70.83 25 20.83 8.33 12.50 8.33
BDT 20(n=7) 4
(57.14%) 28.57 14.28 28.57 14.28 14.28 14.28
BDT 50(n=7) 3
(42.85%) 28.57 14.28 14.28 14.28 28.57 0
BDT 100(n=7) 42.85 14.28 0 28.57 24.28 0 14.28
BDT 500(n=3) 33.33 33.33 0 0 0 0 0
Total frequency
among all
denominations 58% 50% 25% 15% 9% 7% 5%
n= number of sample per denomination
Advan. Biol. Res., 4 (5): 266-271, 2010
269
Table 3: Percentage occurrence of different isolates from different artisans groups (n=56)
Occupational Group E. coli% Klebsiella species% Salmonella species% Vibrio cholera% Pseudomonas species% S. aureus% Bacillus species%
Meat Sellers n=13 69.23 61.54 38.46 7.69 7.69 53.84 7.69
Fish Sellers n=14 85.71 92.85 42.85 28.57 28.57 7.14 7.14
Vegetable Sellers n=11 63.63 54.54 18.18 0 9.09 9.09 0
Food Sellers n=12 50 33.33 0 0 8.33 16.67 16.67
Shop Keepers n=6 50 50 0 0 0 33.33 0
n= number of sample
Table 4: Percentage occurrence of different isolates from different non artisans groups (n=44)
Occupational Group E. coli% Klebsiella species% Salmonella species% Vibrio cholera% Pseudomonas species% S. aureus% Bacillus species%
Office workers n=14 42.86 28.57 0 0 0 14.28 0
Students n=12 41.67 33.33 0 0 0 25 8.33
Bus Conductors n=10 60 30 10 0 0 30 20
Beggars n=08 62.5 62.5 12.5 0 0 50 25
n= number of sample
The level of contaminants was determined from the population. The samples collected from nonpartisan
currencies obtained from the non artisan group namely groups had less contamination as compared to artisans.
office workers, students, bus conductors and beggars. This may be due to less likely to touch contamination
Table 4 indicates that all groups contained some extent of source as compared to artisans. The notes from office
one or more pathogenic microorganisms like Escherichia workers and students however, had less microbial load
coli, Klebsiella, Salmonella, Vibrio cholerae and other than beggars and bus conductors probably indicating
pathogens like Staphylococcus aureus, Bacillus, that they are more likely to be conscious of safe personal
Pseudomonas. Bangladesh paper money notes collected hygiene.
from office workers, students, bus conductors and street The study revealed similar pattern of microbial
beggers were contaminated with E. coli at the rate of contamination in terms of coliforms as those obtained
42.86, 41.67, 60.0 and 62.50%; with Staphylococcus aureus from the previous studies in Bangladesh which was held
at the rate of 14.28, 25.0, 30.0%, respectively. Bacillus at Khulna city, Bangladesh [19]. This study revealed that
species were isolated in small number. Vibrio cholera and about 80 and 16% of old two-taka notes were
Pseudomonas were not detected from non artisan groups contaminated with total coliforrns and fecal coliforrns
but Salmonella found from bus conductors and beggars. respectively. Contamination level was nearly similar for
The presence of pathogenic bacteria on the BDT 10 notes. This study showed the contamination of
Bangladesh currency samples is a case for great concern BDT 2 and BDT 10 only.
because paper money notes probably play a role in the The study was also in accordance with similar pattern
transmission and spread of diseases because each day of microbial contamination as those obtained from the
people use money frequently for their daily activities. previous studies [2,12]. The bacterial isolates recovered
Lower denominations like BDT 1, BDT 2, BDT 10 were Bacillus sp. Citrobacter sp. Enterobacter sp.
denominations were found to have the highest level of Klebsiella sp. Proteus sp. Pseudomonas sp. Serratia sp.
microbial contaminants, on the other hand BDT 500, BDT and Staphylococcus sp. In Iran Shekarforous et al., [20]
100 and BDT 50 had lower level of contamination as found, 13.3, 32.5 and 10.8% of the 120 Iranian currency
compared to small denominations. This accounts for the notes were contaminated with E. coli, S. aureus and B.
facts that these small denominations of Bangladeshi taka cereus, respectively. These authors also found that
are widely used and exchanged many times among all currency notes collected from butchery, bakery,
economic class. Paper currencies recovered from the fish confectionary, fast food, ice cream and poultry meat shop
sellers, meat sellers, vegetable sellers had the highest were contaminated with E. coli at the rate of 60.0, 0.0, 5,
percentage of isolates. The study showed that these 5.0, 0.0 and 10.0 %; with S. aureus at the rate of 55.0, 30.0,
artisan groups do not give much attention to hygienic 10.0, 25.0, 40.0 and 35 %; with B. cereus at the rate of 0.0,
practices, their way of exchanging taka are just touching 10.0, 20.0, 5.0, 20.0 and 10.0 %, respectively. The results in
the goods like fish, meat, vegetables and then exchanging the present study was differ from their study only in case
the taka notes by the same people. This scenario is a of Salmonella because Salmonella was not isolated from
major concern especially in respect of the health status of samples in their study.
Advan. Biol. Res., 4 (5): 266-271, 2010
270
Goktas and Oktay, [11] found similar result as present fishmongers in Rangoon, Myanmar [9]. Piece of money
investigation. They isolated aerobic spore-forming bacilli are in permanent movement, passing in all environments
(91%), Staphylococcus epidermidis (63.3%), that constitute a reservoir and source of various bacteria
Staphylococcus aureus (4.2%), Enterococcus (24.1%), as pathogenic Escherichia coli, which can survive 11
alpha-hemolytic streptococcus (4.1%), Streptococcus days on the inert surfaces [23]. It has been established
pneumoniae (1.7%), Corynebacterium (7.5%), that E.coli 0157:H7and Salmonella enteritidis can
Lactobacilli (10.8%), Klebsiella pneumoniae (31.7%), survive for up to eleven days and up to nine days,
Enterobacter (19.2%), E. coli (17.5%), Proteus (l.7%), respectively on the surfaces of money coins, thus making
Pseudomonas aeruginosa (0.8%), Shigella itpossible for coins to transfer bacteria to human
flexneri(0.8%)from paper money samples of one hundred hands[24]. V. cholerae is primarily an inhabitant of the
twenty currency notes. Currency notes in general were aquatic environment, so water plays an important role in
bacteriologically contaminated, especially with enteric the transmission and epidemiology of cholera [25, 26]. V.
pathogens and potentially pathogens, it was thought that cholerae can be transmitted by Paper money from fish
some measures have to be taken to reduce these ill seller, vegetable seller and food vendors as they use
effects. water frequently for different purposes.
The presence of Staphylococcus species on paper In conclusion the present study clearly demonstrated
money could have been due to rubbing off or may be that Bangladesh paper currency is commonly
surfing from a skin flake. Pathogenic Staphylococci contaminated with pathogenic bacteria. This may play a
harbored either by an asymptomatic carriers or a person significant role in the transmission of various disease
with a disease, can be spread by the hands or expelled Depending on the results of this study, one suggestion
from the respiratory tract. The Staphylococci are natural may be made to peoples to improve their personal health
inhabitants of the animal body, which is the source of consciousness by washing hands after handling of
those found elsewhere. As saprophytes, Staphylococci money notes, taking no foods even snakes after touching
are ubiquitous, being found on normal skin and in the money notes, avoiding using saliva during counting of
nose, mouth and intestine as well as in the air, water, milk paper money notes, avoiding baby to handle money
and sewage and on fomites. Infections occur when notes. In future more complex study using molecular
Staphylococci enter the body through breaks, cuts and methods would be required to accomplish further
abrasions in the skin [21]. Bacillus sp. a vast group of investigation on the antibiotic resistance pattern, plasmid
hardy spore forming species that live in soil and are found profile and pathogenicity of the isolates obtained.
in the environment could also be transferred on money
due to its placement on dirty surfaces or handling with ACKNOWLEDGEMENT
dirty hands. Bacillus produces an emetic exotoxin capable
of inducing disease in man [22]. Therefore, Bangladesh The work was supported by Institute of Food science
paper money play important role to disseminate several and Technology (IFST), Bangladesh Council of Scientific
diseases. Enteric pathogens, such as Escherichia coli, and Industrial Research (BCSIR) under Research and
Vibrio and Salmonella were isolated from paper-money Development Project.
samples obtained from meat sellers and fish sellers. The
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