Abstract
Globally, human health is under threat due to the presence of diseases caused by
microorganisms such as bacteria and viruses. Bacteria are found on almost all surfaces
with which people come into contact and therefore pose a threat to human health.
Antimicrobial resistance is a major health concern as these microorganisms can cause
untreatable diseases. I tested the surfaces found in three buildings on the campus of
the American University of Nigeria in Yola, Adamawa State, for the presence of
harmful bacteria. Swabs collected were streaked on lysogeny broth agar to determine
if bacteria were present. Selective and differential media were used to identify the type
of bacteria found. Also, the samples were subjected to an antimicrobial susceptibility
test using replica plating. The result showed the surfaces were contaminated with
Escherichia coli, Enterobacter aerogenes, and Enterococcus faecalis, with E. coli and
E. aerogenes being resistant to ampicillin. This study showed
INTRODUCTION
Human health is under serious threat globally by microorganisms, especially viral and
bacterial diseases. Bacteria and viruses can be found on surfaces and could potentially
cause harm. Infectious diseases are emerging at an alarming rate and have contributed
to a good number of deaths globally. Although over the past decade the mortality rates
of these diseases have declined, the impact these diseases have on the world remains
substantial. Infectious diseases are the second leading cause of death worldwide, with
57 million deaths occurring each year, as reported by the Center for Disease Control
and Prevention (CDC) (Fauci, Touchette, & Folkers, 2005).
There are increasing global concerns about certain issues such as antibiotic-resistant
bacteria, Zika virus, HIV/AIDS, Ebola virus, and SARS. These diseases have a high
mortality rate and have been identified by the World Health Organization as diseases
likely to cause epidemics (WHO, 2015). In Africa, emerging diseases are a public
health concern not only due to their high mortality rate, but also due to the fact that
developing countries lack good health facilities. Despite countermeasures that have
been developed due to advanced technology (therapeutics and vaccines), infectious
diseases that affect both human health and the economic stability of societies have not
been contained (Morens & Fauci, 2013). Bacteria and viruses that have developed
resistance to antimicrobial agents are more life threatening and are now a serious
public health concern.
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Antibiotic resistance
Antimicrobial resistance has become a major global concern. Aside from bacteria and
viruses, other microorganisms are rapidly developing a resistance to antimicrobial
agents being used to kill them. This evolution makes the treatment of infectious
diseases less effective and, in the long run, may cause death. Though sometimes
viewed as an apocalyptic fantasy, antibiotic resistance, which might allow even minor
injuries to kill, is indeed a reality in the 21st Century (WHO, 2014). Antimicrobial
resistance is a global concern because it will make the treatment of infectious diseases
less effective and prolong illnesses (WHO, 2016). Additionally, organ transplantation,
C-section delivery, and other medical procedures may become more risky due to the
lack of effective antimicrobials.
The increasing global concern for antimicrobial resistance has urged scientists to
further research this issue. Projections made by scientists showed deaths that could be
attributable to antimicrobial resistance yearly by 2050 will be high (Fig.1). Most deaths
will most likely occur in Asia and Africa. Although antimicrobial resistance is
increasing, less researches have been carried out on new drugs to curtail these resistant
pathogens.
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Figure 1. Projections of deaths that could be attributable to antimicrobial resistance yearly by
2050
Resistance in bacteria
Various bacteria have developed a resistance to particular antibiotics. To name a few,
bacteria such as Mycobacterium tuberculosis and Staphylococcus aureus have
developed a resistance to certain antibiotics (Shanks & Peteroy-Kelly, 2009).
Klebsiella pneumoiae, a bacterium known for causing intestinal infections, is resistant
to carbapenem antibiotics and has spread globally, leading to several deaths (WHO,
2016). Additionally, Escherichia coli which causes intestinal infections, is resistant to
fluoroquinolone antibiotics. Currently, many countries around the world have no
effective treatment for these bacteria. Other bacteria, such as S. aureus (Fig.2) and
members of the family Enterobacteriaceae, which are resistant to methicillin and
carbapenem, have also contributed to many untreatable conditions in different
countries (WHO, 2016). The more resistant a strain of bacteria is, the greater the threat
to human health.
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Increasing health risks due to microorganisms
Pathogens can be found on almost all surfaces. Bacteria have the ability to grow
anywhere, even in narrow surfaces, and have the ability to move (Männik et al., 2009).
They can also survive on surfaces for an extended period. Some diseases caused by
bacteria and viruses are life threatening and require immediate attention (Morris,
2016). Prophylaxis such as vaccinations may help lower the probability of getting
infected. Also, good hygiene behaviors and good cleaning practices could lower the
risk of getting infected. Globally, pandemics are rapidly spreading and have left people
concerned about their health. People are more likely to catch diseases caused by
bacteria and viruses in places where people congregate and where they make frequent
contact with non-living objects.
Before assessing the level of microbial contamination on surfaces, hygiene standards
must be considered which are set by regulatory bodies (White, Dancer, Robertson, &
McDonald, 2008). Such standards for pathogens were set by the World Health
Organization (WHO) at <1cfu/cm2
, which means colony forming unit should not
exceed 1 per cm2
.
People in congregated areas are increasingly exposed to health risks daily. Health risks
associated with public places vary; however, bacteria and viruses are the most easily
contracted microorganisms. Microorganisms have several routes through which they
can infect humans, including the mouth and from the hand to the mouth (Butz,
Fosarelli, Dick, Cusack, & Yolken, 1993). Exposure routes of bacteria could be from
shopping carts, offices, restrooms (especially public restrooms), and even on
university campuses.
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Public places and bacteria
The human skin is the main organ of contact with microbes. The skin on its own houses
many bacteria which could be beneficial or harmless. Even though most bacteria found
on the human skin are harmless, S. aureus (Kloos & Musselwhite, 1975),
Corynebacterium minutissimum, and Pseudomonas aeruginosa could cause skin
diseases, such as atopic dermatitis and erythrasma (Ross & Neufeld, 2015).
Studies have shown that bacteria, such as Acinetobacter calcoaceticus and S. aureus,
commonly occur on hospital surfaces. “Hospital” bacteria lead to nosocomial
infections which are infections acquired in hospital settings. In this research, the life
span of the bacteria found on dry hospital surfaces was found to be 13 days, which
could be an additional factor in transmission of nosocomial infections (GetchellWhite, Donowitz, & Groschel, 1989). In the past years, much attention has been paid
to nosocomial infections as the pathogens causing these infections became resistant to
antibiotics. In comparison, there are few studies focusing on infections originating on
public surfaces, such as public telephones, shopping carts, buses, shopping carts, office
furniture, and even on surfaces in university campuses.
Public telephones, which are commonly used in some parts of the world, have been
investigated and are found to harbor pathogens. A particular study carried out in
Melbourne, Australia, identified certain potentially pathogenic bacteria on 20
telephones, such as Acinetobacter anitratus, Enterobacter cloacae, Pantoea
agglomerans, and S. aureus (Ferdinandus, Hensckhe, & Palombo, 2001). From this
study, it was ascertained that telephones could be labelled as potential reservoirs for
pathogens.
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Similarly, transportation systems such as buses and trains harbor pathogens. Transport
systems in Portland, Oregon, USA, were investigated for the presence of pathogens on
seats, floors, and railings (Yeh, Simon, Millar, Alexander, & Franklin, 2011). The
research further analyzed the pathogens for any resistance in certain antibiotics.
Bacteria were found to be more abundant on floors than railings, handles, and seats.
Various species of Staphylococcus, such as S. epidermidis, S. haemolyticus, S.
saprophyticus, S. warneri, and S. xylosus, were found in the buses. Even though there
was no high level of multi-drug resistance, some of the species such as S. xylosus and
S. haemolytics were found to be resistant to gentamycin and erythromycin and could
engage in horizontal transfer of resistance to other species (Yeh et al., 2011).
Subsequently, pathogens are also commonly found on shopping carts, which may be
touched by a large number of people each day. A study carried out across the United
States in 5 grocery stores found E. coli, Yersinia pseudotuberculosis, Klebsiella
oxytoca, and E. cloacae on shopping carts (Gerber & Maxwell, 2012). In offices,
pathogens may be present on surfaces and passed around from one surface to another.
Office equipment and furniture, such as printers and computers, carry these pathogens,
and since they may be not be regularly cleaned, people may have a high chance of
getting infected (Reynolds, Watt, Boone, & Gerba, 2005).
Another “public” place, university campuses, may have high population densities,
which makes it easier for bacteria to spread. Students may be exposed to many health
risks on campuses, which can be contracted from unclean surfaces, cafeteria food, or
bathrooms. Communicable diseases spread easily in places with many people as is the
case with universities. The presence of harmful bacteria in a university can pose a
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threat to the health of students, staff, and faculty (Morris, 2016). These bacteria can be
easily passed around because as people interact in congregated areas, they may pick
up bacteria which could potentially infect them as well as people around them (Shanks
& Peteroy-Kelly, 2009). Students in a university normally make use of computers,
library study tables, cafeteria tables, and restrooms. All these surfaces may harbor
bacteria and could potentially harm people. Unless students are frequently washing
their hands or making use of hand sanitizers, they are more likely to get infected.
Bacteria in universities
Previous studies on bacteria in university campuses have confirmed the presence of
bacteria on surfaces. For example, pathogens such as E. coli have been found on
university tables in clinics, laboratories, and libraries (Burnham, Peterson, Vavrek, &
Haas, 2009). Disinfection protocols may have an impact on the level of contamination.
However, pathogens could still be present regardless of the cleaning being done on
surfaces.
Health risks to students on university campuses could result from the use of public
computers, ingestion of cafeteria food, use of bathrooms, or contact with railings, and
door handles. Cafeterias may be cleaned frequently, but may still harbor bacteria. Food
particles could fall off on the tables in a cafeteria, and if the tables are not probably
cleaned, could be the cause of microbes being present. Contact between students and
these tables could transfer pathogens to people. Bathrooms are generally known to
harbor bacteria. Public restrooms are visited by people with different hygiene
behaviors, which can influence the type of bacteria found on restroom surfaces (Flores
et al., 2011). Urinary Tract Infections (UTIs) may be contracted from the use of public
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toilets, and these are often caused by E. coli, which is commonly found on restroom
surfaces. Depending on the cleaning schedule of a facility, the level of contamination
can be minimal.
In addition to restrooms, computer keyboards in computer labs could also be infected
with bacteria. Campus computers are often accessed by many people daily, and
frequent contact could contribute to high microbial activity. Keyboards may be not
routinely cleaned, as well (Anderson & Palombo, 2008). Microorganisms, such as S.
aureus, Enterobacteriaceae, Enterococcus faecalis, and Bacillus cereus, were found
on computer keyboards in a university computer lab with S. aureus having the highest
colony growth on computers used by multiple people.
Another study conducted in a university in New York City sampled different surfaces
in lecture halls, restrooms, libraries, and cafeterias (Shanks & Peteroy-Kelly, 2009).
The findings revealed that the bacteria found on these surfaces, including E. coli,
Salmonella typhi, S. aureus, were resistant strains. This poses a greater risk to people
on campuses as the diseases caused by these pathogens will be harder to treat (Shanks
& Peteroy-Kelly, 2009). This shows that students may potentially become infected and
that these infections might be hard to curtail due to the resistant strains.
The health risk to students may be even higher if bacteria found on campuses have
developed a resistance. Such resistance is often due to a mutation or frequent use of an
antibacterial agent to clean the surfaces. The bacteria could adapt to the substance
being used to clean and natural selection will take place. The only way to curtail
diseases caused by bacteria resistant to antibiotics is by prescribing the right dosage of
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antibiotics. This is a pressing public health issue.
In addition, the rise in antimicrobial resistance has also been attributed to the frequent
use of antimicrobial agents while cleaning. Some bacteria found on public surfaces
that have resistant strains include E. coli, Salmonella, and Enterococcus species
(Conly, 2002). The bacteria mentioned are often found on campuses. The different
types of bacteria found on surfaces depends on seasons and the different uses of the
buildings (Dunn, Fierer, Henley, Leff, & Menninger, 2013).
The level of microbial contamination in a university depends on several factors. These
include the cleaning schedule practiced by the Facilities Management and, cleaning
materials and products being used (e.g., types of chemicals). The surfaces of a
university campus can be seen as non-critical since the surfaces come in contact mostly
with human skin and is not necessarily contaminated by blood and bodily fluids
(Rutala & Weber, 2001). The U.S.-based Center for Disease Control and Prevention
(CDC) has emphasized the need to disinfect surfaces even though they have not been
contaminated with blood or body fluids (Rutala & Weber, 2001). If the surfaces get
cleaned frequently with a strong disinfectant, the bacterial load will be minimal or
negligible.
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Figure 2. Structure of Staphylococcus aureus
Pathogens could be the cause of the high prevalence of bacterial infections on
campuses. Numerous infections such as typhoid and flu recorded by clinics on
university campuses are most likely transmitted in the dormitories or academic
buildings due to the crowded lifestyle on campuses and contact with surfaces (Pechter,
2011). Inadequate personal hygiene increases the level of contamination and also puts
students at risk of contracting diseases. Some of these diseases are life threatening and
require immediate attention.
The literature on health risks to university students on campuses appears sparse,
particularly for universities in developing countries where standards may be lower.
Therefore, I investigated facilities on the American University of Nigeria (AUN)
campus in Yola, north-eastern Nigeria, for the presence of bacteria on surfaces
commonly touched by students. The aim of my study was to determine which strains
of bacteria occur in these public places and whether any strains were resistance to
antibiotics. The outcome of this work helps raise awareness regarding potential
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harmful pathogens on campus. Findings will be shared with Facilities Management of
the university