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Cutaneous leishmaniasis (CL) is a neglected clinical form that is quite prevalent in Eastern North parts of the country in Sinai Peninsula. Leishmania tropica was identified by previous reports as the causative agent responsible for viscerotropic infections in-patients and experimental animals. Here, we reported the viscerotropic infections from naturally infected rodent Gerbillus pyramidum floweri collected from North-Sinai. Footpad and tail lesions, spleenomegaly, and malformed dark-colored spleen were the characteristic CL symptoms. The spleen of the rodent found positive to amastigote impression smear. ITS-1 DNA was sequenced and revealed 100% identity of the strain in the current study to the other L. tropica sequences identified from the patients with the suspected CL and inhabited the same study area. The current findings confirmed the susceptibility of gerbil to L. tropica, and raise the concerns for the role of rodents as accidental host suffering the infections. The susceptibility of wild and experimental rodents to the same L. tropica strain was also investigated; BALB/c and G. pyramidum were more susceptible to L. tropica (24.33 ± 4.37 and 25 ± 4.58 days post-infection, respectively). Similar viscerotropic pathologies were reported in experimental infection of only golden hamster (≈ 120 days post-infection), and G. p. floweri (≈ 160 days post-infection).

Plants are promising sources of agents useful for the control of vectors of human diseases including leishmaniasis. The effect of Ricinus communis (Euphorbiaceae) and Bougainvillea glabra (Nyctaginaceae), on transmission of leishmaniasis was investigated using them as diets for Phlebotomus papatasi to monitor their effect on life-history traits. P. papatasi were allowed to feed separately on both plants then offered a blood-meal. Fed-females were observed daily for egg-laying and subsequent developmental stages. P. papatasi was able to feed on B. glabra (29.41% females and 46.30% males) and R. communis (5.80% females and 10.43% males). 34.28% of females died within 24-48 hours post-feeding on R. communis, whereas, it was 16.5% in females fed on B. glabra. Overall fecundity of surviving females was reduced compared to controls, reared on standard laboratory diet; however there was no effect on the sex ratio of progeny. Female P. papatasi in the control group had significantly longer life span compared to plant-fed group. Feeding on these plants not only decreased sand fly survival rates but incurred negative effects on fecundity. Findings indicate that planting high densities of R. communis and B. glabra in sand flies-endemic areas will reduce population sizes and reduce the risk of Leishmania major infections.

Sand fly salivary fluid contains numerous proteins that modulate host immune responses to infection and facilitate blood-feeding and establishing Leishmania infection. Salivary proteins are differentially expressed in adaptation to the host, the meal type and ecological factors. We report on the morphometrics and protein composition of salivary glands of colonised Phlebotomus papatasi and P. langeroni sand flies from Egypt. Female glands were dissected at day 1 (D1, unfed), day 2 (D2, sugar-fed), day 3 (D3, blood-fed) and day 7 (D7, blood-digested). The salivary glands are composed of two lobes: heterogeneous in P. papatasi and homogeneous in P. langeroni. Lobe sizes varied considerably with fly age and feeding state; D3 flies had the largest lobe sizes and protein content. The P. papatasi flies had larger lobes and higher protein content than the P. langeroni flies. The P. papatasi D1 flies had 15 protein bands that decreased in the D2, D3 and D7 flies to 10 bands in the Sinai flies and 9 bands in the Alexandria flies. All P. langeroni flies had 12 protein bands but with different intensities. The results reveal inter-specific variation between P. papatasi and P. langeroni, while no intra-specific variation between P. papatasi strains. These results increase our understanding of salivary gland protein composition and blood-feeding behaviour in Old World sand flies with implications for leishmaniasis epidemiology and control., (Copyright © 2012 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.)

Cutaneous leishmaniasis (CL) is prevalent in the Egyptian Sinai Peninsula and previous research has consistently documented the etiologic agent to be Leishmania major. We report the first isolation of Leishmania tropica from human cases of CL in a Northern Sinai community bordering Palestine. Parasite culturing, real-time polymerase chain reaction (PCR), gene sequencing, and restriction fragment length polymorphism (RFLP) analyses indicate CL cases in this community were caused by either L. major or L. tropica (three cases each). Two wild-caught rodents (Gerbillus pyramidum floweri) were infected with L. tropica. Phlebotomus papatasi sand flies were found harboring L. major, however only non-infected individuals of Phlebotomus sergenti, a vector for L. tropica, were caught. Patients with L. tropica had not traveled from the region in over a year, suggesting these cases are autochthonous. This scenario is consistent with an incursion of L. tropica from bordering countries and raises concerns about expansion of this parasite further into Egypt.

The accurate measurement of blood meal size in Phlebotomus langeroni, the potential vector of infantile visceral leishmaniasis in Egypt, is important to determine the number of parasites taken in fully engorged insects. A simple protein content micro-assay is introduced for that purpose. The accuracy of this method was confirmed by hemoglobin estimation method. Laboratory bred P. langeroni were fed artificially on defibrinated human blood and the fully engorged flies were carefully dissected on ice, within 1-10 min after feeding, since the time of dissection is critical. Serial concentrations of the defibrinated human blood were required as standards. Results show that the full blood meal taken by P. langeroni ranged from 0.76-0.94 mm3 of blood with a mean volume of 0.85 +/- 0.02 mm3 and from 0.71- 0.99 mm3 of blood with a mean volume of 0.83 +/- 0.02 mm3 as measured by protein content and hemoglobin estimation methods respectively. The data showed that there is no significant difference (P=0.27) between the two methods in estimating the blood meal size of P. langeroni. In addition, protein content micro-assay had the advantages of being accurate, rapid, sensitive and reliable.

Zoonotic cutaneous leishmaniasis is endemic in Sinai Peninsula. Human cases were recorded from the northern Sinai, however little was known about the disease in southern Sinai. During entomological surveys conducted southern Sinai in summers of 1997-1999, a clinically confirmed ZCL case was encountered for the first time in Sheikh Atiya village in June 1999. The parasite was isolated and identified as L. major using cellulose acetate electrophoresis. A total of 784 phlebotomine sand flies were collected. Sand fly species composition at Sheikh Atiya village showed that P. papatasi and P. alexandri were the most abundant species in the area and each comprises about 47 % of the flies collected. P. sergenti and P. kazeruni occurred in very low numbers. All the female flies dissected (N = 304) were negative for any Leishmania-like flagellates. When the identified isolate was inoculated in the footpads of a clean laboratory colonized Acomys cahirinus dimidiatus, a lesion was developed on the site of inoculation 9 months post injection. The role of P. alexandri and A. c. dimidiatus in transmission of leishmaniasis in southern Sinai remains questionable. Environmental factors contributed to the appearance of ZCL in the area are discussed.

The Alexandria laboratory colony and five field populations of Phlebotomus papatasi (Scopoli) from Egypt were analyzed for genetic variation at 17 enzyme loci. The laboratory colony was characterized by a low level of genetic variation as measured by the average number of alleles per locus (A = 1.70 +/- 0.16) and the average expected heterozygosity (He = 0.06 +/- 0.02). Polymorphism was observed at 23.5% of the examined loci, and genotype frequencies at two loci (PGM, AK-2) were found to deviate slightly from the Hardy-Weinberg equilibrium. In contrast, the average number of alleles per locus for field populations ranged from A = 2.35 +/- 0.20 to 2.76 +/- 0.10, and He ranged from 0.15 +/- 0.03 to 0.21 +/- 0.05. All loci of field populations exhibited polymorphism, ranging from 47.0% to 76.5%, and four to seven loci in each population were found to deviate from the Hardy-Weinberg equilibrium. Deviations in both colonized and field populations were caused by heterozygote deficiency. Despite geographic isolation and some individual deviations from the Hardy-Weinberg equilibrium, no evidence of significant genetic difference was obtained for any of the populations sampled. Calculated indices of genetic distance and genetic identity for the five field populations showed minor variation but were collectively representative of a single, genetically uniform population.

Leishmania infantum zymodeme MON-98 was isolated in El Agamy, Egypt. A total of 15 (1.07%) Leishmania-like infections in the anterior midgut and in the head was found in 1,405 Phlebotomus langeroni (Nitzulescu); none of 1,785 Phlebotomus papatasi (Scopoli) was found infected. Four of the 15 cultures (26.7%) were indistinguishable from a reference L. infantum MON-98 strain using cellulose acetate electrophoresis. The isolation and identification of L. infantum MON-98 from naturally infected P. langeroni confirms that this species of sand fly is the vector of visceral leishmaniasis in El Agamy.

Two immunoassays for malaria sporozoite detection and identification, the immunoradiometric assay (IRMA) and the enzyme-linked immunosorbent assay (ELISA) using the species-specific monoclonal antibodies are routinely performed in our laboratory. We analyzed (573) anopheline mosquitoes of A. sergenti (463), A. pharoensis (81) and A. multicolor (29) collected from Siwa-oases and Faiyum Governorate (two known active malaria foci in Egypt), for detection of P. falciparum and P. vivax sporozoites. P. falciparum sporozoites were detected by both IRMA and ELISA tests in two A. sergenti mosquitoes (one from Siwa 1/389 = (0.26%) and one from Faiyum Governorate 1/74 = (1.35%)). No P. vivax sporozoites were detected. This finding is important in explaining the malaria transmission and provide first incrimination of An. sergenti as the responsible vector of malaria in Siwa-oasis, Egypt.

An Enzyme linked-immunosorbent assay (ELISA) was recently established for the detection of sandfly Naples and Sicilian viruses (SFN and SFS) from laboratory infected as well as wild caught sandflies in Egypt. Optimal dilutions of the reactants including the coating antibodies (Rabbit antiserum), detecting antibodies (Mouse antiserum), conjugate and the time used for incubation of the substrate (ABTS) were determined for both SFN and SFS viruses. The ELISA test showed to be highly specific and sensitive except for the SFN virus which cross reacted with Toscana virus. A total of 1582 sandflies, forming 54 pools (each consisted of 2-109 flies) were collected from different governorates in Egypt (North Sinai, South Sinai, Alexandria, Giza, Qualubyia, Sharkiya and Aswan) in the years 1986-1987 and 1988, and tested for virus detection by the SFN-ELISA and SFS-ELISA. Only one pool (from Giza governorate) revirus was detected. Tests were repeated two times and confirmed by the complement fixation and plaque neutralization tests. The established ELISA technique hold great promise as a routine surveillance tool, permitting rapid, simple, sensitive, specific and inexpensive assay for the detection of the sandfly fever viruses.

Different sampling field techniques were investigated for the study of the natural behaviour of the sand flies in Egypt (South Sinai and Alexandria). Sampling methods were divided into two groups: the first group is techniques for catching alive flies [Active search (Aspirator), CDC-light trap; funnel trap; Fan trap and catches off bait] and the second group is techniques for collecting dead specimens [sticky traps, and illuminated sticky traps (chemical light sticky trap)]. Comparison between the efficiency of the different trapping methods for collecting sandflies indicated that the CDC light trap was the most productive type for species of the genus phlebotomus followed by the illuminated paper traps and then the sticky paper traps. Members of the Sergentomyia group showed to be more attracted to illuminated/sticky paper followed by the sticky paper and then the CDC light traps. In general, sticky paper traps are the most widely used technique for sand fly outdoor collection as it is easy to be used, unexpensive and convenient for the purpose of sandfly surveys.