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Original Article (Pages: 6359-6364)
Prevalence of Cryptosporidium Species in Children Referred to
Central and Hospital Laboratories of Zabol City, South East of
Iran
*Mansour Dabirzadeh1, Mahdi Koshsima shahraki 2, Daryoush Rostami3, Somayeh Bagheri41
1
Associated Professor of Parasitology, Department of Parasitology, Faculty of Medical Science, Zabol
University of Medical Science, Zabol, Iran. 2MSc of Parasitology, Department of Parasitology, Faculty of
Medical Sciences, Zabol University of Medical Science, Zabol, Iran. 3MSc of Anesthesia, Faculty of
Paramedical Science, Anesthesia Group, Zabol University of Medical Science, Zabol, Iran. 4MSc of Biostatic
Science, Department of Biostatics, Faculty of Health, Zabol University of Medical Science, Zabol, Iran.
Abstract
Background
Cryptosporidiosis has a worldwide distribution, and is the commonest cause of diarrhea in children
and immune compromised individuals. Since there is no data available on the prevalence of
Cryptosporidium species (sp.) in Zabol city, thus this study was carried out to assess the disease
prevalence and related factors influencing the disease.
Materials and Methods
In this cross-sectional study, 200 fecal specimens were collected from children referred to the Central
or hospital labs in Zabol city, South East of Iran, during April 2014 to August 2016. Fecal
examination was performed by staining with Ziel-Neelsen acid-fast to find oocysts of the parasite.
The children were grouped according to the age, gender, kind of water supplies, and diarrheic and
non-diarrheic condition. Data were evaluated using SPSS version 13.0 software.
Results
Among the children referred to the Central laboratory, 200 fecal samples from different age groups
were collected. The prevalence of Cryptosporidium species was 9.7% which was higher in children
under 4 years. There was a significant relationship between sources of water supply and diarrheic
children infected with Cryptosporidium (P<0.05).
Conclusion
Cryptosporidiosis is the most infectious disease in Zabol city, especially in children. Healthy water
supply significantly affects the disease prevalence.
Key Words: Children, Cryptosporidium, Diarrhea, Education, Iran.
*Please cite this article as: Dabirzadeh M, Koshsima shahraki M, Rostami D, Bagheri S. Prevalence of
Cryptosporidium Species in Children Referred to Central and Hospital Laboratories of Zabol City, South East of
Iran. Int J Pediatr 2017; 5(12): 6359-64. DOI: 10.22038/ijp.2017.22358.1871
*Corresponding Author:
Mansour Dabirzadeh, Department of Parasitology, Faculty of Medical Science, Zabol Medical University,
Zabol, Iran.
Email: mdabirzadeh20002000@yahoo.com
Received date: Feb.25, 2017; Accepted date: Aug.12, 2017
Int J Pediatr, Vol.5, N.12 Serial No.48, Dec. 2017
6359
Prevalence of Cryptosporidium Species in Children
1- INTRODUCTION
Cryptosporidiosis causes a wide range
of infections in a vertebrate host including
humans (1). This parasite is mainly
transmitted by the fecal-oral route (2).
Water, food and direct contact are a source
of infection (3). Cryptosporidium attacks
the intestinal cell and respiratory system of
vertebrate hosts (4, 5). Cryptosporidiosis
can cause a self-limited diarrheal disease,
but in compromised patients, it can
produce serious and persistent diarrhea,
and can also be chronic and potentially
serious in immune-compromised patients.
In some countries, community outbreaks
have been reported to be associated with
the consumption of polluted water (5).
In
developing
countries,
the
seroprevalence of Cryptosporidiosis is in
the range of 25 to 35%, and represent up to
15%
of
gastrointestinal
problems
especially in children (6). Infection has
been reported in all ages from few months
old babies to a 90 year-old person.
However, many reports indicate that the
prevalence is more in children under 5
years old (5). Many reports from Iran show
that the prevalence rate in diarrheic
children (Iran) was 1.6% in Bander Abbas,
3.25% in Ramser, 5.2% in Tehran, 5.3% in
Hemedan, 7.6% in Tonekabon, 9.2% in
Neghadea, 10% in Oromia, 14.2% in
Mashhad, and 27.2% in Rudhen and
Gagerud . As there is no report on Zabol
city, this research was designed to assess
the disease prevalence and related factors
influencing the disease.
Five species of Cryptosporidium including
C. hominis (previously known as C.
parvum human genotype), C. parvum
(bovine genotype), C. meleagridis, C.
canis, and C. felis have been found to be
responsible for most human infections (7).
2- MATERIALS AND METHODS
2-1. Study design and population
Int J Pediatr, Vol.5, N.5, Serial No.48, Dec. 2017
In this descriptive study which carried
out from April 2014 to August 2016, fecal
samples were collected from children
referred to Central or hospital labs in
Zabol city, Sistan, and Blugestan
provinces, South East of Iran. Also, with
5% significant level, 3% error rate and
4.7% prevalence rate (8), the sample size
was estimated as 192, but for more
confidence, a sample size of 200 was
taken. Zabol is the capital of Zabol
County, Sistan and Baluchestan provinces
in South East of Iran. Zabol lies on the
border with Afghanistan and was referred
to as Sistan until the late 1920s. The
climate of the area is: 28 °C temperature,
42 km/h NW wind, and 25% humidity.
Zabol is located near Lake Hamun and
Hirmand River which irrigates the region.
Lake Hamun is a seasonal lake that is often
dry. The Zabol area is well-known for its
"120-day wind", a highly persistent dust
storm in the summer which blows from
North to South (8).
2-2. Methods
The information of participants including
age, gender, level of education of parent,
kind of water supply, diarrheic or notdiarrheic condition were obtained using a
questionnaire. Fecal samples were kept in
10% formalin for further procedures and
was kept frozen (at -22°C) until required.
Stool smear was prepared by formalinether sedimentation, Sheather's sugar
procedure and stained with modified acid
fast and examined (7).
2-3. Measuring tools
In systemic random sampling, the samples
were taken using a randomized table in
clusters. In this study, a researcher-made
questionnaire was used; for face and
content validity, the questionnaire was
administered to parasitologists and their
recommendations were implemented. The
questionnaire was delivered to 20 patients
and using Cronbach’s alpha coefficient,
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Dabirzadeh et al.
the internal
confirmed.
reliability
(85%)
was
2-4. Laboratory measurements
The stool samples were collected in clean
and labeled boxes and examined upon
reception
for
consistency
and
concentration. The samples were then
mixed with 10% formalin and kept in the
refrigerator for further procedures. After
smear preparation, fixing with methylalcohol was done. All samples were
stained with Modified Ziehl-Neelsen.
2-5. Ethical consideration
Informed consent was taken from all
participants and the study was approved by
the Ethics Committee of the University.
2-6. Data Analysis
Data analysis was
SPSS version 13.0
square and or/Fisher
of less than 0.05
significant.
conducted with the
software using Chiexact test. A p-value
was considered as
3- RESULTS
From the 200 samples examined over a
period of six months, positive oocyst
specimen was detected in 18 samples and
prevalence was 9.7%. For prevalence by
gender, the results showed that from 200
samples, 106 (52%) children are female
while others (47%) are male. There was no
significant relationship between parasite
rate and gender, using the Chi-square test
(p>0.05) (Table.1). The prevalence of
Cryptosporidium oocyst showed that the
highest infection was recorded in children
under 4-year of age (Table.1). Also, Chisquare test showed that there is a
significant relationship between age and
parasite prevalence (p =0.01).
In correlation with kinds of water supplies,
there was
a significant relationship
between children who consumed untreated
pipe-borne drinking or recreational water
and those who used purified water from
bottle or used treated pipe drinking water
in the villages around the city with purified
water system (p <0.05) (Table.2). In
children who have diarrhea and nondiarrhea, there was a significant
relationship between infected and diarrheic
children (p<0.05) (Table.3).
Children who were not breast-fed were
significantly more commonly infected
(83.3%). Although some of them have
both Cryptosporidium spp. and Giardia
lamblia, but there was no relationship
between the two infections (p>0.05). In
relation
to
the
severity
of
cryptosporidiosis, children who were
breast fed, only two children (1.4 %) had a
slight infection (Table.4).
Table-1: The prevalence of Cryptosporidium spp. infection in participants (by gender and age group)
Gender
Positive number
Negative number
Female
11(10.4)
95(89.6)
Male
7(7.4)
87(92.6)
Age group, (year)
Positive number
Negative number
0-4
16(8%)
105(52.5)
>4
2(1%)
77 (38.5)
Int J Pediatr, Vol.5, N.5, Serial No.48, Dec. 2017
6361
Prevalence of Cryptosporidium Species in Children
Table-2: The prevalence of Cryptosporidium sp. infection in the participants (related to kinds of
water supplies)
Cryptosporidium
Water supplies
Water supplies other than pipe
Pipe water supplies
P-value
Positive, n (%)
Negative, n (%)
16(14.5%)
94(85.5%)
2(3.3%)
58(96.7%)
0
30 (100%)
Mineral water or/filtered water
0.009
Table-3: The prevalence of Cryptosporidium spp. infection in the participants (related to diarrheic
and non-diarrheic condition)
Cryptosporidium
Variables
Positive, n (%)
Negative, n (%)
With diarrhea
16
50
Without diarrhea
2
132
P-value
0.000
Table-4: The severity of Cryptosporidiosis in the participants (in relation to breastfeeding)
Mother milk
condition/Cryptosporidiosis
Mother- milk used
No mother- milk used
Slight infection,
Number (%)
2
Moderate infection,
Number (%)
1
Sever infection,
n (%)
0
Summation,
Number (%)
3
7
5
2
14
4- DISCUSSION
It is very difficult to determine the
prevalence rate of cryptosporidiosis, since
there are no data available from many
countries. In one estimate, the prevalence
of Cryptosporidium in patients with
gastroenteritis was 1-4% in Europe and
North America, and 3-20% in Africa, Asia,
Australia, and South and Central America
(9). Laberge et al. estimated that the
prevalence rates of Cryptosporidium
spp.were 1- 3% in industrialized countries,
and up to 10% in developing countries
(based on oocyst excretion) (10).
Cryptosporidiosis exists in more than 106
countries in the world (10). At current
study,
the
prevalence
rate
of
Cryptosporidium spp., in children was
9.75%. The majority of infection appeared
to be correlated with water consumption.
Many studies have emphasized that
Int J Pediatr, Vol.5, N.5, Serial No.48, Dec. 2017
Cryptosporidium spp. is occasionally
found in untreated water (2). Results of
present study showed that children who
used treated or purified water, the infection
rate of Cryptosporidium was zero as the
majority of infection was seen in children
who used unsafe (untreated) water. In this
study, children were randomly selected
and two presented with no diarrheic and
gastrointestinal signs. Thus there was a
significant association between diarrhea
occurrence and Cryptosporidium spp.
infection (P <0.05). Results also showed
that mineral water and pipe water are
moderately good, but water supplies other
than pipe is not suitable. The high
prevalence
of
one
subtype
of
Cryptosporidium in calves and the
frequent detection of this subtype in
humans suggests that parasite fitness
probably plays an important role in the
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Dabirzadeh et al.
transmission of cryptosporidiosis among
cattle and in zoonotic infections (10). The
vast majority of human cryptosporidiosis
is mainly caused by two species, C.
parvum, and C. hominis, but some other
species of this parasite can infect humans
too; C. parvum is more prevalent in rural
or agricultural regions, probably as a result
of zoonotic transmission (11, 12). Since
Zabol is a cow breeding region, the study
predicts a high probability of C. parvum
species infection. This study reports a
prevalence rate higher than in Zahedan and
Gonbad-e Kavoos and Isfahan cities with
prevalence rates of 4.7%, 4.9%, and 4.6%,
respectively (5, 13, and 14). In Bandar,
Abbas Pediatric Hospital, Southeastern
Iran,
the
prevalence
rate
of
Cryptosporidium infection was 7% (13).
of the world, including Iran and more
studies are needed to establish a
relationship with the prevalence and
control, especially in microhabitat without
any systemic water treatment.
4-1. Limitations of the study
Some children and infants were not
accessible due to migration or expatriation
and some information had to be dismissed.
5- CONCLUSION
The present study is the first record of
Cryptosporidiosis among children in Zabol
city, in South East of Iran. It clearly
demonstrated a high prevalence rate of
Cryptosporidiosis among children of less
than 4-year old in this region. More
caution should be shown, especially in
water consumption which is one of the
most important sources of disease.
One study (15) emphasized that the
infection rate of Cryptosporidium spp. in
children less than 1 year is the least
whereas Pal et al. (16) emphasized that
infection rate in children between 0-6
months old is more than in other groups
(5). With regards to the prevalence of
Toxoplasma antibodies in Ahwaz, the
seropositive rate was lowest in new-born
and children under 6 months of age and
highest in persons 14-19 years old (15). In
the present study, the most diarrheic
children were under 4 year-old which is
similar to previous study (15) that reported
in Ahwaz city, only 3 cases were less than
six months of age. Conversely, in the study
of Tahira (India), the highest prevalence of
Cryptosporidium spp. was found in the age
group of 2– 4 years (18.36%) (17).
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6- CONFLICT OF INTEREST: None.
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