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Intestinal parasitism in Peruvian children and molecular characterization of Cryptosporidium species


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Intestinal parasitism was studied in children of Trujillo (Peru) to create a prevention and control program. Fecal samples of 489 children were examined. The general prevalence of intestinal parasitosis was found to be 68%. The most frequent pathogenic enteroparasites were Giardia lamblia (26.4%), Cyclospora cayetanensis (13%), Hymenolepis nana (2%), Hymenolepis diminuta (1.6%), and Cryptosporidium spp. (1%). All these parasites appeared both in diarrheic and nondiarrheic children, except Cryptosporidium, which invariably caused diarrhea. Multiple parasitism was frequent, 45.6% of the children presenting two, three, or four intestinal parasites. Cryptosporidium was the only parasite that was not associated with the others. Only five children were affected of cryptosporidiosis, presenting explosive diarrhea, nausea, and vomiting. Cryptosporidium species and genotypes involved in the infantile cryptosporidiosis were determined by polymerase chain reaction-restriction fragment length polymorphism. Four children were parasitized by Cryptosporidium hominis and only one by Cryptosporidium parvum. Our results confirm that anthroponotic transmission of Cryptosporidium is predominant in Peru.
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Parasitol Res (2006) 98: 576581
DOI 10.1007/s00436-005-0114-7
O. Cordova Paz Soldan
F. Vargas Vásquez
A. Gonzalez Varas
G. Peréz Cordón
J. R. Velasco Soto
M. Sánchez-Moreno
I. Rodríguez Gonzalez
M. J. Rosales Lombardo
Intestinal parasitism in Peruvian children and molecular
characterization of
Received: 27 September 2005 / Accepted: 8 December 2005 / Published online: 24 January 2006
# Springer-Verlag 2006
Abstract Intestinal parasitism was studied in children of
Trujillo (Peru) to create a prevention and control program.
Fecal samples of 489 children were examined. The general
prevalence of intestinal parasitosis was found to be 68%.
The most frequent pathogenic enteroparasites were Giardia
lamblia (26.4%), Cyclospora cayetanensis (13%), Hyme-
nolepis nana (2%), Hymenolepis diminuta (1.6%), and
Cryptosporidium spp. (1%). All these parasites appeared
both in diarrheic and nondiarrheic children, except Cryp-
tosporidium, which invariably caused diarrhea. Multiple
parasitism was frequent, 45.6% of the children presenting
two, three, or four intestinal parasites. Cryptosporidium was
the only parasite that was not associated with the others.
Only five children were affected of cryptosporidiosis, pre-
senting explosive diarrhea, nausea, and vomiting. Crypto-
sporidium species and genotypes involved in the infantile
cryptosporidiosis were determined by polymerase chain
reaction-restriction fragment length polymorphism. Four
children were parasitized by Cryptosporidium hominis and
only one by Cryptosporidium parvum. Our results confirm
that anthroponotic transmission of Cryptosporidium is
predominant in Peru.
Intestinal parasitism among children can be considered in-
dicative of the socioeconomic status and sanitation levels
of a population. The prevalence of enteroparasitoses is
linked to both poor hygiene and inadequate sources of
drinking water. In children, intestinal parasites are as-
sociated with deficient growth, impaired cognition, and
death (WHO 1996). In San Juan de Miraflores, Peru,
Berkman et al. (2002) studied the way in which stunted
growth, diarrhea, and parasitic infection during infancy
affect cognition in late childhood. This work showed par-
asitic infection and stunting during infancy having a strong
adverse effect on cognitive function in late childhood as-
sociated with reduction in IQ scores after adjustment for
socioeconomic, schooling, and other significant factors.
Therefore, the establishment of prevention programs,
control, and treatment of intestinal parasites is fundamental
in developing countries. In Peru, infections from intestinal
parasites are frequent in children. Previous epidemiological
surveys conducted in Trujillo established a prevalence of
30% for Giardia in children under 10 years of age with
acute diarrhea (Vargas et al. 1987). In Puno (Maco et al.
2002), intestinal parasitosis was found to be 91.2%.
Cryptosporidium was first studied in Peru by Soave and
Armstrong (1986), reporting 8.1% prevalence in Lima,
using a total of 111 diarrheic stool samples. Chang (1987)
described a case associated with acute diarrhea in
Oxapampa, while Huaynalaya et al. (1988) detected the
parasite in a female child in Esperanza. Black et al. (1989),
having analyzed fecal samples from 153 children in a
community near Lima, included Cryptosporidium among
the agents causing diarrhea. Sarabia-Arce et al. (1990)
determined cryptosporidiosis in 10% (24 of 248) of the
children admitted to the rehydration ward at Cayetano
Heredia University Hospital, Lima. These researchers
stated that, in children hospitalized for diarrhea, Crypto-
sporidium parvum occurs more frequently in malnourished
subjects. In Sterling et al. (1991), reported a study of 211
Peruvian children and their mothers comparing antibody
titers in mothers milk and incidence of cryptosporidiosis.
There was no significant difference in the incidence (0.17,
0.19, and 0.38, respectively) or duration of infection among
children regardless of the level of maternal antibodies.
According to Berkman et al. (2002), Giardia intestinalis
incidence in Lima ranged from 0 to 4.8 episodes per year
O. Cordova Paz Soldan
F. Vargas Vásquez
A. Gonzalez Varas
I. Rodríguez Gonzalez
Departamento de Microbiología y Parasitología,
Universidad Nacional de Trujillo,
Trujillo, Peru
G. Peréz Cordón
J. R. Velasco Soto
M. Sánchez-Moreno
I. Rodríguez Gonzalez
M. J. Rosales Lombardo (*)
Instituto de Biotecnología, Departamento de Parasitología,
Facultad de Ciencias, Universidad de Granada,
18071 Granada, Spain
Fax: +34-58-243174
during infancy, 86% of children having at least one G.
intestinalis episode during the first 2 years of life. The C.
parvum incidence ranged from 0.56 to 0.61, with 3% of
stool samples testing positive for C. parvum. Cryptospo-
ridium isolated from different regions have different anti-
gens, virulence, infectivity, and sensitivity to drugs and
disinfectants (Fayer and Ungar 1986; Fayer et al. 2000).
Therefore, for the design of control programs, it is vital to
know the species and genotypes of Cryptosporidium in
each region.
Two distinct C. parvum genotypes, genotype 1 (anthro-
ponotic genotype) and genotype 2 (zoonotic genotype),
have been recognized for some time to be responsible for
human cryptosporidiosis. However, such species as Cryp-
tosporidium felis and Cryptosporidium meleagridis, Cryp-
tosporidium muris, and a dog genotype of C. parvum are
also considered responsible for human cryptosporidiosis
(Xiao et al. 2001; Palmer et al. 2003). Recently, Morgan
et al. (2002) proposed a new species, Cryptosporidium
hominis, to denote the human genotype. In Lima, C.
hominis has been the most frequently detected species
(Xiao et al. 2001; Cama et al. 2003).
The Spanish Agency for International Cooperation
(Agencia Española de Cooperación Internacional) and the
regional Agencia Andaluza de Cooperación Internacional
have since January 2004 been financing a project of pre-
vention, control, and treatment of intestinal parasites in
Trujillo, to lower the prevalence of parasitic infections
among children.
For this, it is essential to study the prevalence of in-
testinal parasites as well as the molecular epidemiology of
some of these pathogens. Therefore, in the present work,
we have analyzed the most frequent types of intestinal
parasitism in children from three districts of Trujillo (Peru)
as well as the species and genotypes of Cryptosporidium
involved in infantile cryptosporidiosis, one of the gravest
afflictions in undernourished children in developing coun-
tries (Fayer et al. 2000).
Materials and methods
Study site and sampling
Trujillo (Peru), capital of the department Libertad, has
more than one million inhabitants, concentrated in city
center with marginal populations on the periphery lacking a
sanitary infrastructure.
Temperatures are constant throughout the year, at about
22°C, and relative humidity stays at roughly 70%, being
close to the Pacific Ocean. Rainfall is sparse and restricted
to winter.
The present study on intestinal parasites in children was
conducted in three rural districts on the periphery of the city
of Trujillo: El Porvenir, Buenos Aires, and La Esperanza,
with very low socioeconomic and sanitary levels. El
Porvenir has 18,757 inhabitants, Buenos Aires 8,656, and
La Esperanza 12,404. The three districts have similar living
conditions, in that not all the dwellings have running water,
and thus, inhabitants get water from public fountains or
water trucks, and most of the houses lack toilets.
Prior to the sampling, the sanitation staff of the health
center in each district called a meeting where the study
methods were verbally explained to the parents of the chil-
dren to be studied. A questionnaire was administered to the
parents to return with a fecal sample. The questionnaire
asked the age of the child, the disease, and details on the
diarrhea and its symptoms. After the fecal samples were
turned in, the children were weighed and measured to
complete the questionnaire.
From January to December 2004, stool samples were
collected from children between 1 month and 9 years old to
study intestinal parasites in the schools of each district.
Samples were transported to the laboratory and preserved
in potassium dichromate at 2.5% and kept at 4°C until
macroscopically and microscopically examined. Macro-
scopic inspection determined the consistency and mucosity
as well as the blood and fat contents of the samples. After
examination under a binocular microscope, and afterward a
light microscope, using lugol in some cases, samples were
stained with Ziehl-Neelsen, Giemsa, and Heidenheim and
analyzed by the KatoKatz method for nematode ova
(WHO 1991). Positive fecal samples for Cryptosporidium
were processed to purify the oocysts by potassium bromide
discontinuous gradient (Entrala et al. 2000). The Teleman
concentration was used when other parasites were detected.
Data were compared between diarrheic and nondiarrheic
children using χ
test. Prevalence of intestinal parasites
was studied having a P value <0.02.
Molecular characterization of Cryptosporidium
species and genotypes
DNA extraction
All the positive fecal samples for Cryptosporidium were
processed for DNA extraction. Briefly, 200 μl of fecal
sample in water was suspended in 200 μl of lysis buffer
supplied in the QIAamp DNA mini kit (QIAGEN, USA).
Oocysts were digested using the technique of Robertson et
al. (1993). Genomic DNA was isolated by a QIAamp DNA
stool mini-kit protocol (QIAGEN) directly from the fecal
sample (200 μl/sample). DNA samples were stored at
20°C until further use.
Polymerase chain reaction-restriction fragment length
polymorphism analysis
Cryptosporidium species and genotypes were determined
by nested polymerase chain reaction (PCR) of an SSU
rRNA gene fragment and restriction fragment length
polymorphism (RFLP) analysis as previously described
(Xiao et al. 1999a,b) but using the endonucleases SspI and
For the primary PCR step, a PCR product about 1,325 bp
long was amplified by using primers 5-TTCTAGAGC
GGA-3 (Invitrogen, Spain). Each PCR mixture (total
volume, 50 μl) contained 5 μl of 10× PCR buffer (BioRad,
Spain), 6 mM MgCl
, each deoxynucleoside triphosphate
at a concentration of 200 μM (BioRad), each primer at a
concentration of 100 nM, 1.5 U of Taq polymerase
(BioRad, Spain), 0.5 μl of DNA template, and 0.1 μg/μl
of bovine serum albumin (BSA; BioRad). Each PCR was
performed in a thermocycler (MyCycler, BioRad), under
the conditions described by Xiao et al. (1999a,b). For the
secondary PCR step, a PCR product 819837 bp long
(depending on the species) was amplified by using 0.5 μlof
the primary PCR product and primers 5-GGAAGGGTTG
CAACCTCCA-3 (Invitrogen). The PCR mixture and cy-
cling conditions were identical to the conditions used for
the primary PCR step, except that 3 mM MgCl
was used
in the PCR and BSA was not added.
For the restriction fragment analysis, an aliquot of 20 μl
secondary PCR products was digested in a 50-μl reaction
mixture containing 20 U of SspI (Sigma, Spain) for species
diagnosis, or 20 U of VspI (Sigma, Spain) for genotyping of
C. parvum, and 5 μl of the appropriate restriction buffer at
37°C for 1 h, under conditions recommended by the
As a positive control, a sample of C. parvum genotype 2
was used from cattle belonging to Granja Puleva, Granada
(Spain). The PCR products and a ladder of 1,000 bp
(Sigma, USA) were electrophoresed in a 2.0% agarose gel
and visualized by ethidium bromide staining.
Epidemiological study
A total of 489 fecal samples were collected and analyzed:
225 from El Porvenir elementary school (which had 550
students), 178 from La Esperanza (which had 500 stu-
dents), and 86 from Buenos Aires (which had 100 stu-
dents). The median age of the children was 5.3 years
(interquartile range=4.1). One or more intestinal parasitic
infections were identified in 333 (68%) of the children, 152
(45.6%) of them having multiple parasitic infection by two,
three, or four parasites. The protozoa detected (Table 1)
were Giardia lamblia, Entamoeba coli, Cyclospora
cayetanensis, Iodamoeba buschlii, Endolimax nana, Chi-
lomastix mesnili, and Cryptosporidium spp. Blastocystis
hominis was frequent. The helminths were Hymenolepis
nana and Hymenolepis diminuta. In the three districts
studied, the parasite prevalence proved similar: 26.4% G.
lamblia, 13% C. cayetanensis,2%H. nana, 1.6% H.
diminuta, and 1% Cryptosporidium spp.
Of the 489 children sampled, 147 had diarrhea (defined
as a change in the normal pattern of bowel movements,
with at least three loose stools daily).
Table 1 shows the general prevalence of each parasite
and the prevalence for both populations, children with and
without diarrhea. Of all the intestinal parasites found in the
fecal samples, only Cryptosporidium appeared exclusively
in diarrheic children. In the case of G. lamblia, a slight
123 4 5 6 7
Fig. 1 Molecular diagnosis of Cryptosporidium spp. by a nested
polymerase chain reaction-restriction fragment length polymor-
phism (PCR-RFLP) based on SSU rRNA gene sequences, using
SspI in the digestion. Lane 1, molecular weight marker (1,000 bp);
lanes 26, Cryptosporidium parvum from children; lane 7, C.
parvum from bovine control
Table 1 Prevalence of intestinal
parasites in children of Trujillo
Parasite Diarrheic children, n (%) Nondiarrheic children, n (%) Prevalence (%)
Giardia lamblia 50 (34) 79 (23) 26.4
Blastocystis hominis 35 (23.8) 83 (24.2) 24.1
Entamoeba coli 19 (12.9) 91 (26.6) 22.4
Cyclospora cayetanensis 21 (14.3) 47 (13.7) 13.0
Iodamoeba buschlii 7 (4.8) 43 (12.5) 10.2
Endolimax nana 8 (5.4) 12 (3.5) 4
Hymenolepis nana 3 (2) 7 (2) 2
Chilomastix mesnili 4 (2.7) 5 (1.5) 1.8
Hymenolepis diminuta 1 (0.7) 7 (2) 1.6
Cryptosporidium 5 (3.4) 0 1
difference is also appreciable between the diarrheic
children (34%) and nondiarrheic ones (23%).
Multiple parasitic infections were common, with 333
presenting intestinal parasitosis, 152 (45.6%) of these with
two, three, or four intestinal parasites. The most frequent
cases of multiple parasitism were G. lamblia and B.
hominis, with a frequent association of the two pathogens,
G. lamblia and C. cayetanensis. All the fecal samples in
which these latter two species appeared in association
belonged to children affected by acute diarrhea with nausea
and vomiting.
Cryptosporidium was not associated with other parasites
in any of the five cases diagnosed.
Molecular characterization of Cryptosporidium spp.
Of the 489 children analyzed, only 5 presented Crypto-
sporidium spp., and all had acute diarrhea. Species diag-
nosis was made by digesting the secondary PCR product of
831837 bp with SspI. All the samples generated three
visible bands of 448, 247, and 106 bp (Fig. 1). For C.
parvum to be differentiated from C. hominis, the secondary
PCR product was digested with Vsp I. C. parvum (C.
parvum bovine genotype) produced a visible band of
628 bp, while the human genotype, C. hominis, produced a
band of 556 bp (Fig. 2). Thus, it could be clearly
distinguished that four children had been parasitized by
C. hominis and only one by C. parvum (the latter being
indistinguishable from the control isolate from Granada,
Spain), which was the bovine genotype of C. parvum.
This study determines the intestinal parasites that affect
children from three districts of Trujillo (Peru) as well as the
Cryptosporidium species and genotypes responsible for
infantile cryptosporidiosis, one of the gravest afflictions in
malnourished children in developing countries (Fayer et al.
The prevalence of intestinal parasites in children in this
study was very high (68%) though lower than the 91.2%
found in another study in Puno, Peru (Maco et al. 2002).
The prevalence of pathogenic enteroparasites was also
different. The Puno study reported 6.6% H. nana, 5.5%
Entamoeba histolytica , 3.3% G. lamblia, 2.2% Taenia sp.,
2.2% Ascaris lumbricoides, 1.1% Trichuris trichura, and
1.1% Enterobius vermicularis. Our study found 26.4% G.
lamblia, 13% C. cayetanensis,4%H. nana, 1.6% H.
diminuta, and 1% Cryptosporidium spp. Low intestinal
cestodosis was found possibly because the basic foods of
these children are vegetables and carbohydrates, while
meat, scarcely eaten, is chicken, the cheapest and ap-
parently the only animal consumed in these communities.
The high prevalence of G. lamblia (26.4%) was striking,
this continuing to register one of the highest infection rates
among children in Trujillo since 1987 (Vargas et al. 1987).
C. cayetanensis had the second highest prevalence, at 13%,
this being very high with respect to previous studies in
Lima (Ortega et al. 1994) or Pampas (Madico et al. 1997),
where prevalence among children was 6 and 1%, respec-
tively. Cryptosporidium spp. were detected in 13.3% of
HIV-positive patients in Lima (Cama et al. 2003) and 11%
in diarrheic children in Pampas de San Juan de Miraflores
(Xiao et al. 2001). In our study, only five cases (1%) were
diagnosed, all in diarrheic children. By contrast, such
enteropathogens as G. lamblia, C. cayetanensis, H. nana,
and H. diminuta appeared in diarrheic and nondiarrheic
children (Table 1) with similar prevalence. It has been
demonstrated that the Giardia cysts isolated from the feces
1234 5 67
Fig. 2 Genotype diagnosis of Cryptosporidium by a nested PCR-
RFLP based on SSU rRNA gene sequences, using VspI in the
digestion. Lane 1, molecular weight marker (1,000 bp); lanes 24
human genotype of C. parvum (Cryptosporidium hominis) from
children; lane 5, bovine genotype of C. parvum from a child; lane 6,
bovine genotype of C. parvum from bovine control
Table 2
The most frequent multiple infections by intestinal
parasites in children of Trujillo (Peru)
No. of cases
2 Parasites
G. lamblia + B.hominis 17
E. coli + B. hominis 11
E. coli + G. lamblia 11
G. lamblia + C. cayetanensis 9
E. coli + C. cayetanensis 6
C. cayetanensis + B. hominis 5
B. hominis + I. buschlii 4
3 Parasites
E. coli + B. hominis + G.lamblia 7
E. coli + B. hominis + I. buschlii 6
E. coli + C. cayetanensis + I. buschlii 6
E. coli + C. cayetanensis + B. hominis 6
I. buschlii + G. lamblia + B. hominis 6
G. lamblia + C. cayetanensis + B. hominis 4
4 Parasites
E. coli + E.nana + B. hominis + I. buschlii 2
E. coli + B. hominis + G. lamblia + I. buschlii 2
E. coli + G. lamblia + C. cayetanensis + I. buschlii 2
of asymptomatic children and used to infect gerbils were
more infective than those from symptomatic children
(Astiazaran et al. 2000). Our results underscore the im-
portance of asymptomatic children as carriers in commu-
nities with poor hygiene where there is poor control over
water or food.
Multiple parasitism was frequent, with 45.6% of the
parasitized children presenting two, three, or four parasites.
Notably, in nine cases, G. lamblia and C. cayetanensis were
associated; in four cases, these two were associated with B.
hominis; and in two cases, G. lamblia, C. cayetanensis , E.
coli, and I. buschlii were all found together (Table 2). In all
cases, the children presented acute diarrhea.
Infantile cryptosporidiosis is especially grave in children
who are immune depressed by malnutrition, as there is
currently no completely effective treatment against Cryp-
tosporidium. Therefore, it is fundamental to establish
prevention and control programs against this parasite. In
this regard, it is essential to know the species and geno-
types of Cryptosporidium in each region, as isolates from
different regions have different antigens, virulence, infec-
tivity, and sensitivity to drugs and disinfectants (Fayer and
Ungar 1986; Fayer et al. 2000).
In the present study, five fecal samples from children
with diarrhea contained Cryptosporidium spp. unasso-
ciated with other parasites. By molecular characterization,
we could clearly distinguish that four children were
parasitized by C. hominis and only one by C. parvum.
These data suggest the possibility of two distinct Crypto-
sporidium populations cycling in children in Trujillo. The
most frequent population appears to involve an anthro-
ponotic transmission cycle, fundamentally in humans. The
other population appears to involve zoonotic transmission
from cattle to humans with subsequent human-to-human
and human-to-cattle transmission. The predominance of C.
hominis in children may be due to the fact that bovine
cryptosporidiosis is low because cattle are not corralled but
rather are pastured in the fields. It is known that the
crowding of the animals in the corrals favors the transmis-
sion of the parasite (Xiao et al. 2004). Similarly, other
studies in Peru have also identified C. hominis as the
predominant species (Xiao et al. 2001; Cama et al. 2003).
Transmission of C. hominis in children can be attributed to
their habit of defecating on the ground in the absence of
toilets in houses and schools and, thus, to contamination of
water and food with human waste.
The present work demonstrates the high prevalence of
intestinal parasites in the infantile population considered.
Based on the results of this study, control and prevention
programs are being started against the most frequent
intestinal parasites, and all the affected children have been
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the Agencia Española de Cooperación Internacional and the Agencia
Andaluza de Cooperación Internacional (AI29/04).
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... Because of this, a variety of molecular techniques based on the polymerase chain reaction (PCR) has been developed for Cryptosporidium spp. detection in environmental samples (Soba et al. 2006;Soldan et al. 2006;Trotz-Williams et al. 2006;Santos et al. 2010). ...
... Although DIF is recommended as the gold standard, it has some limitations, such as the use of antibodies that are not species-specific. The variations of PCR have been developed and standardized to detect species of Cryptosporidium in water (Soba et al. 2006;Soldan et al. 2006;Trotz-Williams et al. 2006;Hashimoto et al. 2006, Keshavarz et al. 2009Doi 2009;Pilai 2009). ...
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Cryptosporidium spp. are an emerging pathogen responsible for a large number of diarrhea outbreaks in humans throughout the world. However, the occurrence of epidemic outbreaks caused by this agent in Brazil is poorly known and still needs more attention mainly in the Central-West Region of Brazil, where yet are not studied. Furthermore, there is a need for cheaper or faster methods for detecting Cryptosporidium spp. (given the cost of Envirocheck® filters and IMS kits). Thus, the implementation of standard techniques that enable the identification and quantification of this agent for further study of environmental samples is important. This study aimed at evaluating and comparing immunological techniques for detection of antigen and a real-time PCR for detection and differentiation of Cryptosporidium spp. in samples of treated water. Samples were collected directly from the taps at the entrance of residences and concentrated by a positively charged membrane filter. Oocysts of Cryptosporidium spp. were detected by direct immunofluorescence, ELISA and real-time PCR techniques, and the results were positive in 56.3 % (18/32), 28.1 % (9/32) and 50.0 % (16/32), respectively. The survey results showed for the first time the presence of Cryptosporidium spp. in treated water in the Central-West Region of Brazil. Although real-time PCR showed less positive, it is the one that enables the identification of the species and less expensive when processing a large number of samples. Probably, it would be better to use both techniques, due to their own virtues.
... Renocal-sucrose gradient sedimentation proved to be effective in processing oocysts concentration and purification for flow cytometry [69] . Interestingly, PCR is increasingly used in research and outbreak investigations [70,71] . Trimethoprimsulfamethoxazole (TMP-SMZ) is the drug of choice used as prophylaxis to prevent recurrent episodes among infected immunocompromised patients [72,73] . ...
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Opportunistic parasites are commonly linked with immunocompromised individuals due to weakness in their immune system. Alteration in their cellular and humoral responses leads to hindrance of T and B lymphocytes from efficiently acting against opportunistic pathogens. Accordingly, immunocompromised patients present increased susceptibility to different microorganisms including viral, bacterial, fungal, and parasitic infections. Several conditions are commonly associated with host immune system impairment. Among them enrolled in the present review were malignancy, chronic liver diseases, diabetes mellitus, renal failure, organ transplantation, and inflammatory bowel disease. The most common reported opportunistic parasites include species of Cryptosporidium, Blastocystis, and Microsporidium, as well as T. gondii, C. cayetanensis, I. belli, and S. stercoralis. The objective of the present systematic review is to increase awareness concerning opportunistic parasitosis among Egyptian immunocompromised individuals from 2010 to 2020 with particular reference to their relative detection rates and risk factors of infection. Keywords: Blastocystis, Cryptosporidium, Microsporidium, opportunistic, T. gondii
... As enteroparasitoses constituem um dos principais problemas de saúde pública que afeta a população, sendo que estas são responsáveis por elevados índices de morbimortalidade dos indivíduos, principalmente nos países em desenvolvimento como o Brasil (Rocha, Mendes & Barbosa, 2008.) Nesses países é estimado que em torno de um terço da população geral esteja em precárias condições ambientais, o que favorece a transmissão destes tipos de parasitas (Soldan et al., 2006). ...
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The present study aimed to identify enteroparasites in food handlers described in the literature. This is an integrative literature review, which obtained a total of eleven articles, in which a thorough analysis of the studies available in full in the databases: International Literature on Health and Biomedical Sciences (Pubmed), Academic OneFile and Scientific Electronic Library Online (SciELO). We identified 100 articles, of which after an analysis of the studies, 11 articles addressed the proposed theme and met the inclusion criteria. From the comprehension and analysis of the data obtained by reading the selected studies, it was found that 100% of the works referred to field research. The food handler should maintain good hygiene habits to ensure the production of quality food, and have knowledge to prevent parasite involvement.
... From the data observedthat there was no significant difference between urban (4.1%) and rural (3.3%) infection with Cyclospora , where the rate of infection in urban area was relatively higher than the rural area this may be due to the use of the same sources of drinking water by panties in urban area, though tap water was implicated as the most likely source of contamination, lack of adequate sanitation, and the presence of animals in the household are associated with increased risk of Cyclospora infections [27,44].This result agreed with the results of [45,46],but it was disagree with other studies carried out by [41]in Egypt and [47]in China which most of the infected children were living in rural areas, this may be because of personal hygiene and living environmental conditions. In rural areas, simple toilets, deficiency of sanitary facilities and diffusing feces contamination were commonly recorded, and most people were unaware of health knowledge and good hygiene habits [42]. ...
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he present study aimed to investigate the Cyclospora infection among children attended Pediatric Teac hing Hospital in Sulaimani City and to determine its prevalence among other intestinal parasites. The study started from the 1st of Jun. to the 1st of Dec. 2014. Three hundred stool samples were collected from children aged between6 months to 14 years old from both genders who attended the hospital. Data was collected using a questio nnaire form including information about gender, age, location…..etc. Stool samples were examined by direct wet mount and modified acid-fast stain as a standard method. Usin g Modified Ziehl-Neelsen stain method revealed that 12(4.0%) was positive for Cyclospora oocysts, with no significant difference in the total rate of infection. Theinfection rate in males was (3.9%) while in females was (4.1%),with no significance difference between genders and the rate among children in urban area was (4.1%) while in rural ar eas was (3.3%). According to the age group children from (6 months - 2 years) of age showed the highest (5.6%) prevalence rate, while the lowest rate of infection(3.9%) was recorded among children aged between (3-5 years), w ith no significant difference between the rate of infection and the age groups. Also by applying direct wet mount method the rate of infection was (3.0%), which became in the second level of infection after Entamoeba histolytica (10.3%). Cyclosporias is founded as an endemic case in Pediatric Teaching Hospitalin Sulaimani City for th e first time, were modified acid-fast stain was the most reliable technique for its diagnosis, and must be considered as one of the most important cause of diarrhea amo ng children.
... Intestinal parasites affect approximately 3.5 billion people worldwide and are a public health problem, especially in developing countries, where almost one-third of the population live in conditions favorable to their dissemination. 1,2 Worldwide, amebiasis is the second most frequent parasitic disease, causing around 100,000 deaths each year and contributing towards the high global burden of diarrhea, notably in regions with low economic development and settings with poor sanitation. 2,4 Intestinal parasites are responsible for high levels of morbidity. ...
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Background: Enteral parasitic diseases are a public health problem in nations with low economic development and in settings with poor sanitation. Amebiasis is the second most frequent form of parasitosis, with a high burden of disease. Knowledge of the prevalence of enteroparasitoses in a given region is useful for planning clinical decision-making. Thus, the aim of this study was to estimate the prevalence of enteral parasitic diseases, especially amebiasis, through analysis on stool samples from public and private laboratories in a metropolitan area in southeastern Brazil. Design and setting: Cross-sectional study conducted in the metropolitan region of Belo Horizonte, Brazil. Methods: We evaluated 6,289 fecal samples from one private and one public laboratory. The samples were concentrated by means of spontaneous sedimentation, and those that were positive for Entamoeba histolytica or Entamoeba dispar in optical microscopy analyses were processed to obtain deoxyribonucleic acid, with subsequent identification through the polymerase chain reaction. Results: Among the stool samples, 942 (15.0%) had parasitic infections; 73 (1.2%) of these were helminthic infections and 847 (13.5%) were protozoan infections, caused mainly by Escherichia coli (6.0%), Endolimax nana (5.2%) and Giardia lamblia (1.2%). Infections due to Entamoeba histolytica or Entamoeba dispar occurred in 36 samples (0.6%) and the polymerase chain reaction revealed five (13.9%) as Entamoeba histolytica. Conclusion: The prevalence of enteral parasitic diseases is high in the metropolitan region of Belo Horizonte, although amebiasis may not be a problem.
... It predominately infects the microvillous border of intestinal epithelial cells in immunocompetent as well as immunocompromised hosts (Morgan-Ryan et al., 2002). This species has expanded widely in developing countries including India, Brazil, Pakistan and Peru ( Fig. 3B) (Ajjampur et al., 2007;Araujo et al., 2008;Bushen et al., 2007;Cama et al., 2007;Cheun et al., 2007;Cordova Paz Soldan et al., 2006;Gatei et al., 2008;Gatei et al., 2007;Gatei et al., 2006;Hung et al., 2007;Jex and Gasser, 2008;Muthusamy et al., 2006;Park et al., 2006;Samie et al., 2006). In the industrialized nations such as European countries, Australia, and USA, the distribution of C. hominis infection is as widespread as C. parvum infection. ...
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Cryptosporidium is one of the most widespread protozoan parasites that infects domestic and wild animals and is considered the second major cause of diarrhea and death in children after rotavirus. So far, around 20 distinct species are known to cause severe to moderate infections in humans, of which Cryptosporidium hominis and Cryptosporidium parvum are the major causative agents. Currently, ssurRNA and gp60 are used as the optimal markers for differentiating species and subtypes respectively. Over the last decade, diagnostic tools to detect and differentiate Cryptosporidium species at the genotype and subtype level have improved, but our understanding of the zoonotic and anthroponotic transmission potential of each species is less clear, largely because of the paucity of high resolution whole genome sequencing data for the different species. Defining which species possess an anthroponotic vs. zoonotic transmission cycle is critical if we are to limit the spread of disease between animals and humans. Likewise, it is unclear to what extent genetic hybridization impacts disease potential or the emergence of outbreak strains. The development of high resolution genetic markers and whole genome sequencing of different species should provide new insights into these knowledge gaps. The aim of this review is to outline currently available molecular epidemiology and genomics data for different species of Cryptosporidium.
... B. hominis has long been described as a nonpathogenic protozoan parasite until recently when claims were made that it may be a cause of intestinal disorders [31], [32]. Its frequency in children and adults in developing countries has been widely proven [31], [36], [37]. The presence of five or more B. hominis forms per high-powered field is reported by most laboratories, leaving the clinical significance and the decision to treat to the consulting physician based on clinical evidence [38]. ...
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A study of intestinal parasites in school children in urban and rural areas of Tetouan (Morocco) was conducted. Before it was performed a comparative quantitative study of Faust's and Ritchie's techniques in order to optimize intestinal parasites diagnosis and to determine the techniques effectiveness. The Ritchie's technique resulted the most effective for the detection of both protozoan and helminthes, especially under conditions of low parasite burdens. The prevalence of intestinal parasites was 65% and 71% in rural and urban areas respectively. Overall, the prevalence of protozoa that was found was higher than the one detected for helminths. The most frequent of the intestinal parasites was the protozoa Blastocystis hominis and the most frequent pathogenic protozoa were Giardia lamblia followed by Cyclospora cayetanensis. Among the helminths Trichuris trichiura, Hymenolepis nana, H. diminuta, Enterobius vermicularis, Taenia saginata, Ascaris lumbricoides and Fasciola hepatica. Giardia lamblia showed notable differences between boys and girls in urban areas. To compare the prevalence of parasites in children with the same sex in different areas the differences were only found in boys infected by B. hominis, G. lamblia and E. nana. Multiple parasitism appeared in 29% of the samples presenting two, three or four parasites.
... The Ethiopian scenario is not different from other SSA countries as the Federal Ministry of Health of Ethiopia (FMoH) [2] reported that annual visits of more than half a million cases in the outpatient departments of health facilities are as a result of intestinal parasitic infections including helminthiases. This number might not represent the actual burden as some of the health facilities lack the appropriate diagnostic methods as well as failure of detecting lower parasite burden [3]. The Ethiopian custom of using medicinal plants for the treatment of intestinal parasites has existed for many generations. ...
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Embelia schimperi has been used for the treatment of intestinal parasites especially tapeworm infestations for centuries in Ethiopia. However, there is lack of scientific based evidences regarding the efficacy, safety and phytochemical analysis of this plant despite its frequent use as an anthelmintic. This study has therefore evaluated the efficacy and acute toxicity of E. schimperi thereby generating relevant preclinical information. The anthelmintic activities of the crude hydroalcoholic extract of E. schimperi and the isolated compound, embelin, were conducted using in vivo and in vitro models against the dwarf tapeworm, Hymenolepis nana, and the hookworm, Necator americanus, respectively. LD50 of the crude hydroalcoholic extract was determined using Swiss albino mice following the OECD guidelines. Chemical characterization of the isolated embelin was conducted using UV-spectroscopy, HPLC and NMR. In the acute toxicity study no prominent signs of toxicity and mortality were recorded among the experimental animals at the highest administered dose. Hence the LD50 of the plant was found to be higher than 5000 mg/kg. In vivo cestocidal activity of the crude hydroalcoholic extract of E. schimperi showed 100 % parasite clearance at 1000 mg/kg, while the diammonium salt of embelin showed 85.3 % parasite clearance at 750 mg/kg. The in vitro anthelminthic activity study revealed that the LC50 value of the crude extract and albendazole were 228.7 and 51.33 μg/mL, respectively. The results clearly indicated that the hydroalcoholic extract of E. schimperi and the diammonium salt of the isolated compound embelin had anthelmintic activity against hookworm larva in vitro and H. nana in vivo. Hence the findings of this study showed Embelia schimperi appears to possess some anthelmintic activity that may support the usage of these plants by local traditional healers to treat helminthic infestations.
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Objetivos: Determinar la prevalencia y los factores asociados a coccidiosis y amibiasis intestinal en niños de edad escolar del distrito de Chongoyape, Chiclayo, Perú. Material y métodos: Estudio transversal de tipo relacional entre noviembre del 2014 y enero del 2015 en 133 escolares. Para recolectar la información sociodemográfica y de saneamiento se usó un cuestionario estructurado. La detección de los parásitos se realizó en muestras seriadas de heces. Para los coccidios intestinales se realizó examen microscópico directo (EMD), técnica acido resistente modificada (TARM) y ELISA coproantígenos para Cryptosporidium spp., mientras que para la amibiasis se usó EMD y ELISA coproantígenos para Entamoeba hystolitica. Resultados: El 6,8% (9/133) de la muestra presentó coccidiosis intestinal, 3,8% (5/133) con Cryptosporidium spp., y 3,0% (4/133) con Cyclospora cayetanensis. No se detectó Cystoisospora belli. El 4,5% (6/133) de la muestra presentó E. histolytica. El factor asociado en ambas parasitosis fue el consumo de agua insalubre (p=0,001 y p=0,026 respectivamente), mientras que el contacto con animales se asoció a la coccidiosis intestinal (p=0,013). Conclusiones: La coccidiosis y la amibiasis intestinal son frecuentes en niños de la población estudiada, evidenciando su importancia como problema de salud pública y la necesidad de un diagnóstico específico y rutinario en las instituciones de salud de la región.
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Biological data support the hypothesis that there are multiple species in the genus Cryptosporidium, but a recent analysis of the available genetic data suggested that there is insufficient evidence for species differentiation. In order to resolve the controversy in the taxonomy of this parasite genus, we characterized the small-subunit rRNA genes of Cryptosporidium parvum, Cryptosporidium baileyi, Cryptosporidium muris, and Cryptosporidium serpentis and performed a phylogenetic analysis of the genus Cryptosporidium. Our study revealed that the genus Cryptosporidium contains the phylogenetically distinct species C. parvum, C. muris, C. baileyi, and C. serpentis, which is consistent with the biological characteristics and host specificity data. The Cryptosporidium species formed two clades, with C. parvum and C. baileyi belonging to one clade and C. muris and C. serpentis belonging to the other clade. Within C. parvum, human genotype isolates and guinea pig isolates (known as Cryptosporidium wrairi) each differed from bovine genotype isolates by the nucleotide sequence in four regions. A C. muris isolate from cattle was also different from parasites isolated from a rock hyrax and a Bactrian camel. Minor differences were also detected between C. serpentis isolates from snakes and lizards. Based on the genetic information, a species- and strain-specific PCR-restriction fragment length polymorphism diagnostic tool was developed.
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Community-based studies of diarrhea etiology and epidemiology were carried out from July 1982-June 1984 in 153 infants residing in a poor peri-urban community near Lima, Peru. Study infants had nearly 10 episodes of diarrhea in their first year of life. Diarrhea episodes were associated with organisms such as Campylobacter jejuni, enterotoxigenic and enteropathogenic Escherichia coli, Shigella, rotavirus, and Cryptosporidium. These organisms appeared to be transmitted to infants in the home through animal feces, through contaminated water and food, and by direct person-to-person contact. A particularly important route of transmission may have been weaning foods, which were often contaminated because of improper preparation and inadequate cleaning of utensils. Improved feeding practices, along with avoidance of animal feces and improved personal and domestic hygiene, should be considered important interventions in reducing the high incidence of diarrhea in infants in developing countries.
Cryptosporidium parasites from a cross-sectional study conducted in two national hospitals in Lima, Peru were genetically characterized to deteimine the diversity of Cryptosporidium spp. in HIV-positive people. A total of 2,672 patients participated in this study and provided 13,937 specimens. Cryptosporidium oocysts were detected by microscopy in 354 (13.3%) of the patients. Analysis of 951 Cryptosporidium- positive specimens from 300 patients using a small subunit rRNA-based PCR-RFLP tool identified 6 genotypes; Cryptosporidium hominis was the species most frequently detected (67.5%), followed by C. meleagridis (12.6%) and C. parvum (11.3%). Cryptosporidium canis (4.0%), C. felis (3.3%), and Cryptosporidium pig genotype (0.5%) were also found. These findings indicate that C. hominis is the predominant species in Peruvian HIV-positive persons, and that zoonotic Cryptosporidium spp. account for about 30% of cryptosporidiosis in these patients.
There are 10 valid species of Cryptosporidium and perhaps other cryptic species hidden under the umbrella of Cryptosporidium parvum. The oocyst stage is of primary importance for the dispersal, survival, and infectivity of the parasite and is of major importance for detection and identification. Because most oocysts measure 4–6 μm, appear nearly spherical, and have obscure internal structures, there are few or no morphometric features to differentiate species and in vitro cultivation does not provide differential data as for bacteria. Consequently, we rely on a combination of data from three tools: morphometrics, molecular techniques, and host specificity. Of 152 species of mammals reported to be infected with C. parvum or an indistinguishable organism, very few oocysts have ever been examined using more than one of these tools. This paper reviews the valid species of Cryptosporidium, their hosts and morphometrics; the reported hosts for the human pathogen, C. parvum; the mechanisms of transmission; the drinking water, recreational water, and food-borne outbreaks resulting from infection with C. parvum; and the microscopic, immunological, and molecular methods used to detect and identify species and genotypes.
To test the hypothesis that breast milk of nursing mothers may afford children protection against cryptosporidiosis, a prospective cohort study was carried out in the young peoples' community of San Juan de Miraflores near Lima, Peru. Mothers and newborn children were sorted into cohort groups based on the mothers' breast milk antibody response to Cryptosporidium sporozoites using an antibody-capture enzyme-linked immunosorbent assay to detect parasite-specific immunoglobulin A. Children were monitored for Cryptosporidium infection using an indirect immunofluorescence assay. Of 211 mothers enrolled in the study, 39 (18.5%) had high breast milk antibody titers, 107 (50.7%) had medium titers, and 65 (30.8%) had low titers. Sixty-one episodes of Cryptosporidium infection were detected in 50 children of these mothers. Eleven (22%) had mothers in the high antibody titer group, 20 (40%) had mothers in the medium titer group, and 19 (38%) had mothers in the low titer group. The prevalence of infection within children of each group was 0.17, 0.19 and 0.38 respectively. There was no significant difference in the prevalence or duration of infection among children of the different groups. The data does not support the notion that there is protection from Cryptosporidium infection afforded children whose mothers have demonstrable breast milk antibodies against the parasite.
A retrospective, hospital-based case-control study was used to investigate whether there were any clinical characteristics that could distinguish Cryptosporidium parvum-infected children with diarrhea from other non-C. parvum-infected children with diarrhea. Ten percent (24 of 248) of children admitted to a rehydration ward at Cayetano Heredia University Hospital, Lima, Peru, were infected with C. parvum. The 24 patients infected with C. parvum (cases) were matched to an equal number of noninfected patients (controls). C. parvum-infected patients were more likely to be malnourished than were children without this infection (P less than 0.05). Also nosocomial infection caused by C. parvum occurred in three severely malnourished patients, two of whom died. No other clinical or laboratory characteristics were found that would distinguish children with diarrhea caused by C. parvum from other children with diarrhea. In children hospitalized for diarrhea C. parvum infection occurs most frequently in malnourished children.
Cryptosporidium is a newly recognized human pathogen associated with severe enteritis and, perhaps, cholecystitis in immunocompromised patients, particularly those with the acquired immunodeficiency syndrome, and significant, though self-limited, diarrheal illness in the immunocompetent host. As more physicians look for this pathogen, the number of reported cases of cryptosporidiosis continues to increase. Although the prevalence of cryptosporidiosis in humans is not yet known, recent studies suggest that it is a common cause of diarrhea worldwide, particularly in young children. The pathogenic mechanisms by which Cryptosporidium causes enteritis and the factors of human host defense essential for eradication of this parasite have not been delineated. Acid-fast staining of stool is a quick and reliable way of diagnosing cryptosporidiosis. Although a vast array of therapeutic agents has been tried for this disease, there is currently no known effective therapy for cryptosporidial infection.