Vol.2, No.8, 951-956 (2010)
Copyright © 2010 SciRes. http://www.scirp.org/journal/HEALTH/
Openly accessible at
Survey of food handlers in bukas (a type of local
restaurant) in Lagos, Nigeria about typhoid fever
Stella I. Smith1*, Chimere O. Agomo2, Moses Bamidele1, Bolanle O. Opere3, Olusimbo O.
1Molecular Biology and Biotechnology Division, Nigerian Institute of Medical Research, Lagos, Nigeria; *Corresponding Author:
2Biochemistry and Nutrition Division, Nigerian Institute of Medical Research, Lagos, Nigeria
3Department of Microbiology, Lagos State University, Lagos, Nigeria
4Department of Microbiology, University of Lagos, Lagos, Nigeria
Received 30 March 2010; revised 26 April 2010; accepted 27 April 2010.
Purpose: The study was conducted to survey
the knowledge and behavioural practices of
food handlers in bukas (a type of local restaurant)
in Nigeria with the aim of assessing the hygiene
practices of food handlers and whether they
were knowledgeable about typhoid fever and its
mode of transmission. Methods: One hundred
and seventy four (174) Respondents were ad-
ministered questionnaires on their sociode-
mographic characteristics, behavioural practices
and knowledge of typhoid fever. Results: Ma-
jority of the food handlers drank pure water
(32.1%), borehole water (32.6%) and public tap
water (31.1%) at the about the same frequecy.
More than half (62.2%) washed their hands with
water only before eating while 27.7% did not
wash their hands always before preparing food.
After using toilets, 71.9% washed their hands
with soap and water while 28.1% washed their
hands with only water. When asked if they had
heard about typhoid fever 90% said they had
heard, out of which15.6% did not know how it
was contracted while the others had partial
knowledge. Conclusion: Food handlers play a
prominent role in the transmission of typhoid
fever and so it is important that the food
handlers are well informed about their hygiene
status and the causes of typhoid fever trans-
mission and ways by which typhoid fever
spread is prevented. This will go a long way to
help reduce the incidence of typhoid fever in the
Keywords: C Food Handlers; Salmonella; Typhoid
Fever; Buka
Salmonella enterica serovar Typhi is the causative agent
of typhoid fever and the route of transmission is fae-
cal-oral. There are certain areas where the infection is
most common such as areas where the sanitary con-
ditions are unhygienic and there is lack or poor supply of
water. Polluted water is the most common source of
typhoid. Other sources occur with infected vegetables
fertilized by night soil, shell fish taken from sewage
contaminated beds, and eating of raw contaminated milk
and milk products [1].
The symptoms of typhoid fever include a sudden onset
of sustained fever, severe headache, nausea and severe loss
of appetite. An estimated 700,000 deaths occur from an
annual incidence of approximately 21 million cases [1].
In developed countries where there are adequate
sanitary facilities, only sporadic cases from typhoid fever
occur at fairly constant levels with very few cases
coming from countries endemic with typhoid fever. The
reverse is the case for developing countries where there
are no proper sanitary facilites. A study by Todd et al.
[2-4] revealed that the food workers tested were either
asymptomatic or were at the stage before infection shows
symptons and so were not conscious of their infections.
The report strongly suggested the hands of the food
handlers as the most likely route through which the
pathogen could be transmitted. The implicated pathogens
were norovirus, hepatitis A virus, Salmonella, Shigella
and Staphylococcus aureus. Experiments conducted by
the authors on pathogen survival indicated that trans-
mission depends on species, delivery route of the ino-
culum, the temperature and period of pathogen exposure,
contact surface type, and relative humidity.
Other common food worker associated pathogens are
stapylococci or streptrococci from skin and nasopha-
ryngeal or oropharyngeal infections. This gave a strong
S. I. Smith et al. / HEALTH 2 (2010) 951-956
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backing on the importance of effective hand hygiene and
the use of barriers throughout the work shift.
In another study from Ethiopia by Andargie et al. [5]
on the prevalence of bacteria and intestinal parasites
among food handlers, Salmonella species was not
isolated from the food handlers. However other path-
ogens were implicated in the stool and finger nail
content of the food handlers and their findings further
stressed on the importance of food handlers as potential
sources of infections.
A study by Malhotra et al. [6] on changes in know-
ledge, attitudes and self-reported hand washing practises
among food handlers three months after providing them
health education showed the importance of health
education in food and personal hygiene. The authors
suggested including health education in the existing
guidelines for food establishment in Delhi and other
The personal and food hygiene practices in South
African delicatessen sections of retail outlets were ex-
amined using structured questionnaires [7]. The authors
concluded on the need for proper and continuous trai-
ning in personal and general hygiene not only for food
handlers but also for management.
Another study in Nigeria by Okojie et al. [8] using
structured questionnaires to assess food handlers in a
Nigerian University, corroborated the view of vanToder
et al. [7].
Recently, Smith et al. [9-10], reported on the pre-
valence of S. enterica serovar Typhi amongst food
handlers. S. enterica serovar Typhi accounted for 5.7%
of the total microorganisms isolated from the food
handlers and 40% of Salmonella spp. Food handlers are
located in various areas in Lagos metropolis, a city in
Nigeria and depending on the cost of food, the food sold
to those of the lower class are usually very cheap and
sometimes not prepared in hygienic conditions. In ad-
dition, the environment could be close to a very dirty
gutter and with so much litter around and flies.
This study was conducted to assess the knowledge
about typhoid fever and hygiene practises of food
handlers in buka (a type of local restaurant) in Lagos.
One hundred and seventy four (174) questionnaires were
taken based in a previous survey aiming to determine the
prevalence of S. enterica serovar Typhi amongst clinical
samples [11].
The study is a cross-sectional descriptive one con-
sisting of 174 “asymptomatic” food handlers in bukas. It
was carried out in Lagos, a city in Nigeria between June
2006 and March 2007. The respondents were sampled
by convenient sampling and interviewed using semi
structured questionnaires for data collection. A total of
230 food handlers were asked to participate in the study
and 56 (24%) declined to participate. The semi-structured
questionnaire was administered and filled by a member
of the research team. There were 25 questions in all and
none was leading in nature and the questionnaire was
administered in English and where the food handlers
were not well educated to understand the language,
pidgin English a language common amongst majority of
Nigerians was used. Verbal consent was obtained from
the food handlers before the questionnaire was admini-
stered. An average of four people worked in the bukas
selected and it was noted that for bigger bukas of about
50 food handlers, there was no cooperation amongst the
food handlers. The reason why the selection made was
with smaller bukas. However there was cooperation in
one local government were the food handlers were
gathered in groups (of 8) for questionnaires to be
administered. Eleven markets were visited in all. All the
respondents interviewed cooked food on site and they
are usually on ground very early to prepare food.
The questionnaire had a brief introduction about
typhoid fever, the Respondent’s background, behavioural
practices and buka.
Other questions included whether there was a toilet
facility and how it was used. The last part of the ques-
tionnaire included Respondent’s knowledge of how
typhoid fever was contracted and if there was prior
knowledge of the disease or diagnosis and treatment given.
Method of data analysis: The date was analysed using
Epi info 6.0.
3.1. Sociodemographic Characteristics
The respondents were mostly females 77.6%. Their ages
ranged between 15 and 62 years with a mean of 32.6 ±
11.3 years while the men comprised 22.4% of the
respondents with a mean of 30.1 ± 8.3 years. There was
no significant difference (P = 0.47) between the ages of
the males and the females.
When the food handlers were assessed in terms of
tribe more than half of the respondents were Yoruba by
tribe (64.9%), followed by Ibos (21.8%). The other
tribes comprise 13.3% (Table 1). Out of eleven markets
visited Yaba, Oshodi and Agboju markets (40%) were
the markets where most of our Respondents were
interviewed (Table 2).
3.2. Behavioral Practices
The major sources of drinking water were Borehole 62
S. I. Smith et al. / HEALTH 2 (2010) 951-956
Copyright © 2010 SciRes. http://www.scirp.org/journal/HEALTH/Openly accessible at
(32.6%), packaged (“pure”) water 61 (32.1%) and public
tap 59 (31.1%). The Well water was not popular as a
source of drinking water 6 (3.2%) (Table 1). Some of
the respondents used more than one water source for
For cooking and washing of plates the major sources
of water were borehole 54.3%, well water 24.0% and
public tap 20.2%.
Most of the respondents (93.5%) ate some foods with
their bare hands. The foods eaten with bare hands are the
staple foods like Eba/starch (23.7%), amala/lafu (17.7%),
Fufu (17.2%), yam (14.4%) and Semovita (12.0%).
All the respondents washed their hands before eating
however only 37.8% washed their hands with soap and
water while 62.2% washed their hands with only water.
Table 1. Sociodemographic characteristics of food handlers in
bukas in Nigeria.
Characteristics Frequency %
Age (years)
15 – 40 138 79.3
>40 36 20.7
Male 39 22.4
Female 135 77.6
Educational Status
No formal education 10 5.7
Primary 140 80.5
Post-primary 23 13.2
Post secondary 1 0.6
Hand-washing practice
after toilet
Yes with soap and
water 125 71.8
Yes with only water 52 28.2
*Sources of drinking water
Borehole 62 32.6
Public tap 59 31.1
Pure water 61 32.1
Well 6 3.2
Others 2 1.1
Tribe of Respondents
Yoruba 113 64.9
Ibo 38 21.8
Delta 11 6.3
Hausa 3 1.7
Edo 1 0.6
Togolese 1 0.6
Others 7 4.0
*The Respondents had more than one source of drinking water.
Table 2. Shows the market and the number of Respondents
interviewed in each market.
MARKET Freq Percent
AGBOJU 20 11.0
IYANA IBA 13 7.0
KETU 14 5.0
MILE 2 3 1.0
OSHODI 22 12.0
YABA 30 17.0
Total 174 100.0
Foods in bukas sampled were prepared mostly by both
the owners and hired workers (51.7%). In other cases,
foods were prepared by only the owners (26.7%) and the
hired workers (21.7%).
The owners who washed hands always before prepar-
ing food were 54.3% while 27.7% did not always wash
their hands. Before preparing food 42.0% of the hired
workers washed hands always; 39.8% washed some-
times while 18.2% did not wash their hands.
Majority of the respondents (77.7%) were located in
markets with toilet facilities while 22.3% did not have
toilet facilities in their markets. After using toilets,
71.8% washed their hands with soap and water while
28.2% washed their hands with only water. The sources
of water used for washing hands were public tap (54.7%)
and water storage container (35.8%). Other sources in-
cluded ‘pure water’ (7.4%), water brought from home
3.3. Symptoms Felt by Respondents during
Episodes of Typhoid Fever
From the questionnaire, 69.4% of the respondents re-
ported headache, diarrhea (4.1%), abdominal cramps
(30.6%), fever (26.5%), vomiting (2.0%), weakness
(34.7%), dizziness (26.5%), tiredness (40.8%), and loss
of appetite (20.4%) as what they experienced during
episodes of typhoid fever.
3.4. Type of Apartment
More than half of the respondents lived in a one-room
apartment, 67.3%, while the rest lived in self-contained
flat (16.3%) and other types of accommodation (16.3%).
The average number of persons living in the different
types of apartments was 4.1 ± 1.9, 4.1 ± 1.8 and 6.3 ±
S. I. Smith et al. / HEALTH 2 (2010) 951-956
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1.8 for one-room, self-contained and other types of ac-
commodation respectively.
3.5. Respondent’s Knowledge of the Disease
Ninety percent (90%) of the respondents have heard of
typhoid fever while 10% have not heard. On how the
disease was contracted, 38.9% said contaminated water,
23.8% contaminated food, 4.3% not washing hands.
Other responses were dirty environment 8.6%; too much
work/stress 7.0%, walking in the sun 2.7%; while 5.9%
did not know.
Thirty-eight point two percent (38.2%) said they had
suffered from typhoid fever while 61.0% had not; 0.8%
were not sure if they had had typhoid. However, major-
ity of the respondents (50.8%) said they had household
members who had suffered from typhoid, 33.3% did not
have, while 15.8% did not know if any member of their
household had had typhoid.
3.6. Sources of Information
On how they knew the fever was typhoid, 38.5% said
they went for a blood test, 37.6% was told by a doctor,
and 13.7% was told by a nurse. Only 3.4% went for stool
test, 3.4% knew from past experience, and 2.6% knew
through other ways.
Majority of the typhoid fever were treated in a hospi-
tal 60.0%. Others were treated in a chemist 23.5%;
“agbo” (a local herb concoction) was used in 15.3% of
cases while 1.2% did nothing.
3.7. Prior Treatment Sources
Twenty respondents (11%) had had previous antibiotic
treatment before being diagnosed as having typhoid fe-
ver. The drugs used were ampicillin 6 (30.0%), amoxil
5(25.0%), chloramphenicol 3(15.0%), ampiclox 3 (15.0%).
Tetracycline, ampicillin and fulcin were used by 5% of
these respondents respectively.
The respondents sought for treatment from doctors
17(85%), Nurses 4(20.0%) and self treated 8 (40.0%).
Thus some sought treatment from more than one source.
Where investigated, the diagnosis was based on labo-
ratory result (60.0%) and clinical presentation (40.0%).
Self treated means they were able to access antibiotics
and other forms of treatment without a doctor’s pre-
From this study, 27.7% of owners wash hands some-
times before preparing food, while 18.2% of the hired
workers do not wash their hands at all. This is alarming
because one of the main sources of pathogen transfer
such as Salmonella spp is through improper hand wash-
ing. Since pathogens of faecal, nose or throat and skin
origin are most likely to be transmitted by the hands,
there is need for the food handlers to be informed about
the importance for effective hand hygiene and other bar-
riers to pathogen contamination. In another Nigerian
study by Okojie et al. [8], on the assessment of hygiene
among food handlers in a Nigerian University, there was
a very low frequency of hand hygiene and a poor
knowledge and practise of food hygiene amongst the
food handlers. A report by Mohan et al. [13] on the car-
rier state of S. Typhi and intestinal parasites and per-
sonal hygiene, showed that 0.47% of the food handlers
studied harboured S. Typhi and it was attributable to their
poor personal hygiene.
Non-typhoidal Salmonella was isolated from the stool
of 10% of asymptomatic food workers in Thailand [14].
In the US, Buchwald and Blaser [15] estimated that
200,000 individuals may be excreting non-typhi Salmo-
nella at any one time and many of these excretors would
be food workers.
During food production and preparation, since both
healthy and infected workers stay at work for several
days, the possibility therefore exists for healthy indi-
viduals to be continually exposed to these infected
workers [4]..
These infected workers could be in the aymptomatic
stage and still harbour millions of infectious organisms
in their stools without any sympton of infection. To
prevent pathogen transmission therefore one needs to
adhere strictly to effective hand washing barrier creation
to prevent such pathogens from being transmitted to
foods [4].
In a study from Japan on Salmonella carriage rate
amongst food workers, 331,644 faecal specimens were
collected from workers in hotels, supermarket, food
factories, and restaurants; only 0.032% of the faecal
samples harboured Salmonella, and the most common
serovars were Agona, Corvallis, Infantis and Enteritidis
A report in Nigeria by Smith et al. [9] showed that
5.7% of the food handlers harboured S. Typhi. However
from a report from Ethiopia by Andargie et al. [5]
Salmonella spp was not isolated from the food handlers
working in a caferteria in the University.
From this study, 28.2% of food handlers wash their
hands with water only after using the toilet. This also
implies improper hand-washing and the possibility of
Salmonella transmission to the foods prepared or eaten
by the food handlers. The importance of hand washing
with soap cannot be overemphasized; as a report by
Fewtrell et al. [17] suggested that intensive hygiene
education that includes promoting hand washing with
soap, proper dirt and faecal disposal, disallowing open
S. I. Smith et al. / HEALTH 2 (2010) 951-956
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Openly accessible at
de-faecation by children, has been shown to reduce di-
arrhoeal disease incidence in young children.
This highlights the risks that occur in food preparation
venues where there are opportunities for faecal and nasal
contamination of hands on a regular basis and a lack of
adequate hand washing.
It has been reported that three percent of typhoid fever
survivors become permanent carriers, with the organism
present in the gallbladder, biliary tract, or rarely the
intestine or urinary tract [18].
The authors concluded that asymptomatic Salmonella
excretors have a low risk of transferring Salmonella
from their stools by their hands to food and suggested
hand contamination with Salmonella to more likely be
due to inconsistent hand washing during preparation of
meat [19].
Salmonella Typhi and Salmonella Paratyphi also can
be detected in urine during systemic infection [20],
emphasizing the importance of effective hand hygiene
even for food workers who use the toilet only for
The majority of the food worker-associated outbreaks
reviewed by Greig et al. [2] and Todd et al. [22-23]
involved transmission of the pathogen to food by food
handlers’ hands. In fact hand contact was described as a
factor in 40% of the 816 outbreaks, and the investigators
specifically mentioned that the food handlers were not
wearing gloves in 1.3% of the outbreaks. The authors
further stated that bare hand contact may have con-
tributed to more outbreaks if gloves had not been worn
regularly, but data on wearing of gloves were not
recorded during their investigations. In our own study
there was no data on wearing of gloves. Investigators
[22-23] also noted that provision of sinks and toilet
facilities with adequate water supplies were lacking in
such studies. These Researchers also identified street
vendors as the source of faecally contaminated foods,
particularly in developing countries. Toilets, toilet paper,
and clean water for hand washing often are not readily
available, which is a phenomen that is also true for the
typical Nigerian buka.
A study conducted by Senthilkumar and Prabakaran
[12] showed that the food handlers played prominent
role in transmission of typhoid bacilli through different
food products and water and the carrier state of typhoid
was observed in the age group 15-45 years. Another
study carried out by Sur et al. [24] showed that Re-
sidents in areas with a high risk for typhoid fever were
made of those with lower education levels and economic
status, bigger families, and lived close to areas where
there are rivers and streams. Our study did not however
look into the literacy rate but the food handlers sampled
had bigger families and low economic status.
Although 90% had heard about typhoid fever, 15.6%
did not know how it is contracted. In addition, when
asked how they knew the fever they had was caused by
typhoid fever only 3.4% said they went for a stool test.
Eighty point five percent (80.5%) of the food handlers
had primary education and this could probably account
for the poor hygiene practise amongst the food handlers.
It is interesting to note that although some had no formal
education some of them had heard about typhoid fever.
Another report by Andargie et al. [5] suggested from
their study that the reason for infection amongst the food
handlers surveyed was due to their low education level
(6.3%). In contrast, the study by Zain and Naing [25],
reported that although the food handlers surveyed with
no formal education accounted for 10.5% there was no
significant difference in the attitudes and practice bet-
ween trained and untrained food handlers.
There is, however a potential source of bias in this
study since the convenient sampling method was used
and large number of food handlers in a particular region
were not interviewed.
It is recommended for public health policy and practice
that in order to reduce transmission of typhoid fever and
other communicable diseases among food handlers, hand
washing, universal use of plastic gloves and proper
waste disposal system should be mandatory. In addition,
there should be access to clean water and sanitary toilets
near food service areas.
The Government (both State and Federal) should also
embark on enlightenment campaigns on a regular basis
and health hygiene training and retraining sessions
should be undertaken for these food handlers to create
awareness about the importance of health hygiene and
the risks asociated with non compliance with the rules
and regulations that govern food handlers.
Source of funding: International Foundation for Science (IFS) grant no:
E/4020-1 to SIS.
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