الفهرس 
LeishmaniasesOnly 14 pages are availabe for public view
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Abstract
In the present study the risk factors associated with cutaneous
leishmaniasis were identified – through investigating the disease in 143
human cases at the Saudi hospital in Hajjah north western Yemen. All
patients were Yamani national and have not traveled to endemic areas.
The study was approved by Hajjah University. No information on the
patient has been presented in this research. Leishmaniases are generally
zoonosis involving Leishmania parasite a mammalian reservoir and the
vector species (Phlebotomus) which transmit the parasite to human host
However, anthroponotic leishmaniasis is also known due to L.
donovani and L. tropica. Recently the presence of animal reservoirs is a
matter of debate.
The results of this study are summarized in the following:
1. The clinicoepidemiologic profile of 143 cases
Dry type lesions were seen in (98.6%) and wet type lesions in
(1.4%) of patients
The number of lesions ranged between 1-16 on different parts of the face and extremities
The infection was higher in males than females (93 male, 50
females). This may be due to males are more exposed to sand fly
bites outdoors.2- Microscopic examination of the parasite
Giemsa stain smears revealed amastigotes in 106 of patients and 37 were
negative
The parasite density in the lesions was high indicating active
transmission of the disease
Most patients of CL (30.1%, 23.1%, 16.1) were from Kohlan-Afar, Al’
Saragi, and Hajjah City respectively, the rest of patients (4.9%, 0.7) were
from the other villages of Hajjah. This indicates the endemicity.
3- Leishmania species identification by polymerase chain reactionrestriction
fragment length polymorphism (PCR- RFLP)
The biotical material was scraped from both Giemsa stain and methanol
fixed smears, and used for molecular characterization in the same
experiment.
The technical approach developed in the present study, in which the
sequences representing all samples were a lined with L. tropica reference strain yielded identical sequences with L. tropica and was easy to
implement.
4- The suspected reservoir hosts were surveyed in Hajjah governorate.
20 feral dogs, 30 mice, two rock hyraxes, three bats were collected.
These animals were all asymptomatic
Smears from liver, spleen, and sometimes skin were stained by
Giemsa stain and examined by microscopy, no amastigotes were
detected.
Leishmania species identification using the PCR technique was
negative since no amastigote DNA was detected This suggested that CL in Hajjah is transmitted from person to
person (Anthroponotic) through the bites of the sand fly vector.
5- The sand fly vector
1. A total of 1074 sand flies was collected, 838 sand flies were
collected by sticky paper traps and 236 were collected by CDC
light traps.
2. The collected of sand flies belong to two genera Phlebotomus and
Sergentomyia the genus included six species of Phlebotomus
Phlebotomus bergeroti Parrot, P. orientalis Parrot, P. arabicus
Theodor, P. alexandri Sinton, P. sergenti Parrot, and P. papatasi
(Scopoli). The genus Sergentomyia included ten species
Sergentomyia fallax (Parrot), S. africana (Newstead), S. dreyfussi
Parrot, S. taizi (Lewis), S. christophersi (Sinton), S. tiberiadis
(Adler, Theodor & Lourie), S. yusafi (Sinton), S. multidens
(Guggisberg & Teesdale), S. dolichopa, and S. antennata (Adler,Theodor & Lourie).
3. All the Phlebotomus collected were known as vectors of
cutaneous leishmaniasis or visceral leishmaniasis in the Old
World, but the species belonging to the genera Sergentomyia are
important component of the sand fly fauna, and are generally
considered of no medical importance.
4. In the present study, the density and the distribution as well as the
seasonal abundance of sand flies were studied for one year. This
kind of research is required for the application of the control
programs.5. The topography of the study area (Hajjah governorate) is diverse,
ranging between Tihama Lowland and mountainous areas.
6. Three transect were selected for the study: Tihama Lowland (0-
800m), West Highland (801- 1600m), Interior Highland (1601-
2400m) above sea level. The results can be summarized in the
following:
Phlebotomus sergenti: the known vector of L. tropica was
more abundant at the Highland (801- 2400m above sea level)
Phlebotomus papatasi: the known vector of L. major was
presented, only in few numbers in Lowland.
Phlebotomus bergeroti: the suspected vector of L. major
was abundant in the higher altitude 801- 1600m above sea level.
Phlebotomus orientalis: the known vector of L. donovani
causing visceral leishmaniasis was present in all transects with an
affinity to high altitudes.
Phlebotomus arabicus: suspected vector of L. tropica was present in all transects with preference to the West Highland (801-
1600m above sea level). The role of this species in the transmission
of Leishmania tropica in Yemen needs to be investigated.
Phlebotomus alexandri: the suspected vector of L.
donovani in some parts of the world was abundant in the Tihama
Lowland (0- 800m) the role of this species in transmitting L.
donovani in Yemen needs to be investigated.
7. PCR technique was used to detect Leishmania DNA in 150 females
of Phlebotomus species: 82 P. bergeroti, seven P. orientalis, 40 P.
arabicus, 16 P. alexandri, and five P. sergenti. No Leishmania DNA was detected in any of the species sequenced. The negative result was
suggested to be due to the small sample size.