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\begin{document}

\title{Microbial contamination of hands with or without the use of electric
toilet seats with water spray (bidets) after defecation}



\author[1]{Shigeharu Oie}%
\author[1]{Mai Suetomi}%
\affil[1]{Sanyo-Onoda City University}%


\vspace{-1em}



  
  \date{May 05, 2024}


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\selectlanguage{english}
\begin{abstract}
\textbf{Objective:} Electric toilet seats with water spray (bidets) are
gaining in popularity all over the world. However, the extent of
reduction in microbial contamination of hands with the use of bidets
after defecation is not known. \textbf{Methods:} The microbe
contamination of hands with and without the use of bidets after
defecation with the participation of 32 nursing students was studied.
Double gloves were worn on the dominant hand and four layers of toilet
paper were used to wipe the buttocks after defecation and the microbe
contamination of the second glove (outer glove) of the double gloves was
examined. The volunteers were free to select flow volume, wash time of
the bidet and even the type of bidet for use was left up the individual.
\textbf{Results:} Without the use of a bidet, the average value \selectlanguage{ngerman}±
standard deviation of the number of microbe attached to the gloves was
39,449.3 ± 77,768.3 colony forming units (cfu) / glove; however, it was
4,146.9 ± 11,427.7 cfu / glove when a bidet was used.The number of
microbe adhering to gloves was significantly reduced when a bidet was
used (p \textless{}0.0001, Wilcoxon singed-rank test).
\textbf{Conclusion: It was discovered that reduction of microbe
contamination of hands was possible with the use of bidets after
defecation.}%
\end{abstract}\selectlanguage{ngerman}%



\sloppy


\textbf{INTRODUCTION}

Electric toilet seats with water spray (bidets) were developed in Japan
and the use of bidets is spreading throughout the world. However, it has
not been made clear on whether the use of bidets has any effect on the
hygiene of hands. Studies on the effectiveness of bidets in the
prevention of microbial contamination of hand after defecation have been
done only with \emph{in vitro} experiments.\textsuperscript{1}Therefore,
this experiment examined the microbial contamination of the hands of 32
volunteers after defecation with and without the use of bidets.

\textbf{METHODS}

The number of microbe adhering to gloves after defecation of 32 nursing
students (17 males and 15 females) with and without the use of bidets
was examined. Double gloves (Plastic Glove No. 2500 Kyowa Ltd., Osaka,
Japan) were worn and the number of microbe adhering to the gloves after
wiping with four layers of toilet paper was examined. Four sheets of
toilet paper were used because a survey conducted by the Japan Sanitary
Equipment Industry Association with 1,748 subjects on the number of
sheets and the length of toilet paper for wiping revealed that 4 sheets
of toilet paper was the most frequently used
amount.\textsuperscript{2}The outer gloves of the double gloved hands
that held the toilet paper were peeled and placed into bottles
containing 200 mL of normal saline and were subjected to sonication at
36 kHz (Since Sonic 100, Ikemoto Scientific Technology Co., Ltd., Japan)
for 5 min. \textsuperscript{3,4}Each sample was diluted 10-fold,
100-fold and 1000-fold in sterile saline; four aliquots (0.25 mL each)
of each dilution and of an undiluted sample were plated on four
trypticase soy agar (TSA) . In addition, the remaining saline sample
(\emph{ca.} 200 mL) in the bottle was filtered through a 0.22micrometer membrane
filter (diameter, 5 cm; Nippon Thermo Scientific, Wilmington, NC, USA),
which was placed on TSA plates.\textsuperscript{4} These TSA were
cultured aerobically at 35 for 48 hr. In the case where the undiluted
inocula on TSA became less than 5 colony forming units (cfu), the cfu
with the membrane filtration technique on TSA were counted. This
experiment was conducted with the participation of volunteer nursing
students from the Ube Frontier University (Ube City, Yamaguchi
Prefecture). Therefore, permission was obtained from the Ube Frontier
University Ethics Review Committee (Title: Hands and finger
contamination after defecation - comparison of use with and without warm
water washing toilet seats (bidets) -, Approval date; November 8, 2017,
Examination certificate management number; 17007).

\textbf{RESULTS}

In the pre-experiment (5 subjects), when the cfu of microorganism
attached to gloves after defecation cultured aerobically with TSA and
anaerobically with GAM agar were compared, all five individuals had more
cfu with TSA. Therefore, in this experiment, anaerobic culture with GAM
agar was not performed, and only aerobic culture with TSA was performed.

Table 1 shows the number of microbe attached to gloves after defecation
with and without the use of bidets. The average \selectlanguage{ngerman}± standard deviation of
the colony forming units (cfu) attached to gloves after defecation
without using a bidet was 39,449.3 ± 77,768.3 / glove, however, it was
4,146.9 ± 11,427.7 / glove when a bidet was used. The amount of microbe
adhering to the glove after defecation was significantly reduced when a
bidet was used (\emph{p} \textless{} 0.0001, Wilcoxon singed-rank test)
(Table 1).

\textbf{DISCUSSION}

We have already reported the effectiveness of bidets with \emph{in
vitro} experiments. Namely, a model of the buttocks was smeared with
artificial diarrheal feces containing \emph{Serratia marcescens}, and
wiped by the participants wearing disposable gloves with 4 sheets of
toilet paper after the use and non-use of bidets. Subsequently, the
presence of \emph{S. marcescens} on the surface of the gloves was
quantified. After using the bidets, the mean count ± standard deviation
of \emph{S. marcescens} was 0.067 ± 0.249 cfu/ glove, and it was 4,275 ±
6,069 cfu/ glove when bidets was not used. The results obtained were
that the cfu of \emph{S. marcescens} was significantly lower when the
bidets were used (\emph{p} \textless{} 0.00001) prior to wiping the
artificial diarrheal feces. Although the effect of bidets in this
fieldwork was not as significant as that of the previous \emph{in
vitro}experiment, the effectiveness of bidets was confirmed as in the
previous\emph{in vitro} experiment. It is estimated that microbial
contamination from feces of hand after defecation has a major impact on
the spread of intestinal infections such as norovirus gastroenteritis,
\emph{Clostridioides difficile}related infections, and enterohemorrhagic
\emph{Escherichia coli}infections.\textsuperscript{5-10} For example,
outbreaks resulting from food handlers who are infected or subclinical
infected with the norovirus and does not sufficiently wash or disinfect
their hands after using the toilet, then handling
food.\textsuperscript{11-14}Accordingly, hand hygiene after defecation
is of course important,\textsuperscript{15} but it is also important to
prevent fecal contamination of the hand after defecation as much as
possible. In this experiment, the use of bidets was found to be
effective in reducing microbial contamination of fingers after
defecation. Although bidets were originally developed for medical use,
they are presumed to be also effective in the prevention of spreading
intestinal infections.

In conclusion, the use of electric toilet seats with water spray
(bidets) was an effective method in reducing faces adhering to hands at
the time of defecation.

\textbf{CONFLICT OF INTEREST}

The authors declare no conflict of interest.

\textbf{AUTHORS CONTRIBUTIONS}

SO developed the design of the study, participated in date collection,
planned and performed date analysis, drafted the article. MS
participated in the design of the study, participated in date collection
and analysis, critically revised the article.



\textbf{REFERENCES}

\begin{enumerate}
\tightlist
\item
  Oie S, Aoshika H, Arita E, Kamiya A. The use of electric toilet seats
  with water spray is efficacious in maintaining hand hygiene in
  experimental model. \emph{Jpn J Infect Dis.} 2018;71(4):306-308.
\item
  Japan Sanitary Equipment Industry Association. ``A present status
  survey on the use of toilet paper.''
  \textless{}http://www.sanitary-net.com.com/trend/research/toiletpaper2016.html\textgreater{},
  accessed 8 November, 2017.
\item
  Jeng DK, Lin LI, Hervey LV. Importance of ultrasonication conditions
  in recovery of microbial contamination from material surfaces. \emph{F
  Appl Bacteriol} . 1990;68(5): 479-484.
\item
  Oie S, Huang Y, Kamiya A, Konishi H, Nakazawa T. Efficacy of
  disinfectants against biofilm cells of
  methicillin-resistant\emph{Staphylococcus aureus} . \emph{Microbios} .
  1996;85(345):223-230.
\item
  Lyman WH, Walsh JF, Kotch JB, Weber DJ, Gunn E, Vinjé J. Prospective
  study of etiologic agents of acute gastroenteritis outbreaks in child
  care centers. \emph{J Pediatr.} 2009;154(2):253-257.
\item
  Wu HM, Fomek M, Schwab KJ, et al. A norovirus outbreak at a
  long-term-care facility: the role of environmental surface
  contamination. \emph{Infect Control Hosp Epidemiol.} 2005;26
  (10):802-810.
\item
  Worsley MA. Infection control and prevention of \emph{Clostridium
  difficile} infection. \emph{J Antimicrob Chemother.} 1998;41(Suppl
  C):59-66.
\item
  Ekanem EE, DuPont HL, Pickering LK, Selwyn BJ, Hawkins CM.
  Transmission dynamics of enteric bacteria in day-care centers.\emph{Am
  J Epidemiol} . 1983;118 (4):562-572.
\item
  Black RE, Dykes AC, Anderson KE, et al. Handwashing to prevent
  diarrhea in day-care centers. \emph{Am J Epidemiol} . 1981;113
  (4)\textbf{:} 445-451.
\item
  Salama MF, Jamal WY, Mousa HA, Al-Abdulghani KA, Rotimi VO. The effect
  of hand hygiene compliance on hospital-acquired infections in an ICU
  setting in a Kuwaiti teaching hospital. \emph{J Infect Public Health}
  . 2013;6 (1):27-34.
\item
  U.S. Department of Health and Human Services CDC. ``Updated Norovirus
  outbreak management and disease prevention guidelines.'' \emph{MMWR
  Morb Mortal Wkly Rep.} 2011 March 4;60(3). \textless{}
  https://www.cdc.gov/mmwr/pdf/rr/rr6003.pdf\textgreater{} , accessed 8
  January, 2020.
\item
  Mathijs E, Stals A, Baert L, et al. A review of known and hypothetical
  transmission routes for noroviruses. \emph{Food Environ Virol} .
  2012;4 (4):131-152.
\item
  Hall AJ, Wikswo ME, Pringle K, Gould LH, Parashar UD. Division of
  Viral Diseases, National Center for Immunization and Respiratory
  Diseases (CDC). Vital signs: foodborne norovirus outbreaks - United
  States, 2009-2012. \emph{MMWR Morb Mortal Wkly
  Rep.}2014;63(22):491-495.
\item
  Tsuchiya Y, Sahara A, Jinbo T, et al. A foodborne outbreak of
  norovirus caused by bread. \emph{Jap J Food
  Microbiol.}2015;32(3):153-158.
\item
  Green LR, Selman CA, Radke V, et al. Food worker hand washing
  practices: an observation study. \emph{J Food Prot} . 2006;69
  (10):2417-2423.
\end{enumerate}

\textbf{Table 1. Contamination of hand after defecation with or without
the use of toilet seats with water spray (bidets)*}\selectlanguage{english}
\begin{longtable}[]{@{}llll@{}}
\toprule
Experiment participant no. & Colony forming units (cfu)/glove & Colony
forming units (cfu)/glove & Sex\tabularnewline
\midrule
\endhead
& When bidet not used & When bidet used &\tabularnewline
1 & 4.1\selectlanguage{ngerman}×10\textsuperscript{5} & 5.4\selectlanguage{ngerman}×10\textsuperscript{4} &
Male\tabularnewline
2 & 1.7\selectlanguage{ngerman}×10\textsuperscript{5} & 664 & Male\tabularnewline
3 & 1.0\selectlanguage{ngerman}×10\textsuperscript{5} & 3.4\selectlanguage{ngerman}×10\textsuperscript{4} &
Male\tabularnewline
4 & 8.5\selectlanguage{ngerman}×10\textsuperscript{4} & 2.4\selectlanguage{ngerman}×10\textsuperscript{4} &
Male\tabularnewline
5 & 7.8\selectlanguage{ngerman}×10\textsuperscript{4} & 131 & Male\tabularnewline
6 & 7.2\selectlanguage{ngerman}×10\textsuperscript{4} & 115 & Female\tabularnewline
7 & 7.1\selectlanguage{ngerman}×10\textsuperscript{4} & 328 & Female\tabularnewline
8 & 5.6\selectlanguage{ngerman}×10\textsuperscript{4} & 38 & Female\tabularnewline
9 & 2.4\selectlanguage{ngerman}×10\textsuperscript{4} & 310 & Male\tabularnewline
10 & 2.4\selectlanguage{ngerman}×10\textsuperscript{4} & 720 & Male\tabularnewline
11 & 2.2\selectlanguage{ngerman}×10\textsuperscript{4} & 5 & Male\tabularnewline
12 & 2.1\selectlanguage{ngerman}×10\textsuperscript{4} & 7.2\selectlanguage{ngerman}×10\textsuperscript{3} &
Male\tabularnewline
13 & 1.8\selectlanguage{ngerman}×10\textsuperscript{4} & 352 & Female\tabularnewline
14 & 1.7\selectlanguage{ngerman}×10\textsuperscript{4} & 816 & Female\tabularnewline
15 & 1.7\selectlanguage{ngerman}×10\textsuperscript{4} & 4.8\selectlanguage{ngerman}×10\textsuperscript{3} &
Male\tabularnewline
16 & 1.5\selectlanguage{ngerman}×10\textsuperscript{4} & 1.0\selectlanguage{ngerman}×10\textsuperscript{3} &
Male\tabularnewline
17 & 1.4\selectlanguage{ngerman}×10\textsuperscript{4} & 420 & Male\tabularnewline
18 & 1.1\selectlanguage{ngerman}×10\textsuperscript{4} & 66 & Male\tabularnewline
19 & 1.0\selectlanguage{ngerman}×10\textsuperscript{4} & 134 & Male\tabularnewline
20 & 7.0\selectlanguage{ngerman}×10\textsuperscript{3} & 1.5\selectlanguage{ngerman}×10\textsuperscript{3} &
Female\tabularnewline
21 & 5.0\selectlanguage{ngerman}×10\textsuperscript{3} & 848 & Female\tabularnewline
22 & 4.0\selectlanguage{ngerman}×10\textsuperscript{3} & 172 & Female\tabularnewline
23 & 4.0\selectlanguage{ngerman}×10\textsuperscript{3} & 360 & Male\tabularnewline
24 & 2.0\selectlanguage{ngerman}×10\textsuperscript{3} & 38 & Male\tabularnewline
25 & 2.0\selectlanguage{ngerman}×10\textsuperscript{3} & 15 & Female\tabularnewline
26 & 2.0\selectlanguage{ngerman}×10\textsuperscript{3} & 63 & Male\tabularnewline
27 & 1.0\selectlanguage{ngerman}×10\textsuperscript{3} & 29 & Female\tabularnewline
28 & 1.0\selectlanguage{ngerman}×10\textsuperscript{3} & 265 & Female\tabularnewline
29 & 320 & 97 & Female\tabularnewline
30 & 244 & 18 & Female\tabularnewline
31 & 228 & 124 & Female\tabularnewline
32 & 184 & 75 & Female\tabularnewline
Mean \selectlanguage{ngerman}± standard deviation ** & 39,449.3 \selectlanguage{ngerman}± 77,768.3 & 4,146.9 \selectlanguage{ngerman}± 11,427.7
&\tabularnewline
\bottomrule
\end{longtable}

* Wiped with 4 layers of toilet paper.

** \emph{p} \textless{}0.0001 (Wilcoxon signed-rank test)

\selectlanguage{english}
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