The transmission of parasites of the genus Leishmania involves a large diversity of mammalian reservoir hosts. However, many of these are yet to be identified, mainly in isolated biotopes such as the Amazonian rain forest. Furthermore, the trophic preferences of insect vectors have major epidemiologic implications. In this study, we developed a molecular tool for the identification of blood meals of phlebotomine sand flies. This assay is based on specific amplification and sequencing of the blood meal–derived single copy prepronociceptin (PNOC) gene, which is used as a target in phylogenetic studies of mammals. Sand flies were identified simultaneously with the blood-meal identification, using molecular analysis of a ribosomal locus. After a systematic assessment of the sensitivity and specificity of polymerase chain reaction amplification of the PNOC gene using human fed sand flies, the assay was tested on wild-caught sand flies. This work has important implications for the discovery of new Leishmania reservoir hosts and for a better understanding of complex parasite life cycles.

Background: Leishmania killicki was originally described in 1980 in southeast Tunisia. It was also recently reported in Lybia and Algeria. Nevertheless, neither vector nor reservoirs of this parasite are known. The identification of the vector and the animal reservoir host of L. killicki is critical for the establishment of an efficient control strategy. Findings: blood, popliteal lymph node, spleen, bone marrow, liver and skin were collected from 50 rodents in 2009 in south western Tunisia. Samples were smeared onto glass slides, cultured on NNN medium and tested by polymerase chain reaction for Leishmania detection. Parasites were detected by PCR from 10 Psammomys obesus and from two Ctenodactylus gundi. Parasite identification was performed simultaneously by internal transcribed spacer 1 PCR-RFLP and by PCR sequencing. Both Leishmania major and Leishmania killicki were identified from infected Psammomys and Ctenodactylus gundi respectively. Conclusion: This is the first report of Leishmania killicki identified from Ctenodactylus gundi in Tunisia. This result supports the assumption that C. gundi is a potential reservoir for Leishmania killicki.

To evaluate the prevalence of intestinal parasites among patients in Hail, Northwestern Saudi Arabia. Stool samples were collected from 130 patients (69 females and 61 males) in Hail General Hospital. Each sample was examined by direct wet mount microscopic examination using both normal saline and Lugol's iodine preparation and concentration techniques using salt and formol-ether solutions. Permanent stained smears were performed for intestinal coccidian using modified Ziehl-Neelsen technique. The overall prevalence of intestinal parasitic infection was 45.38% (59 cases). Forty-four (33.84%) were found to be infected with one or more intestinal protozoa, 5 (3.84%) were infected with helminthes and 10 (7.69%) had mixed infection with both helminthes and protozoa. The most common intestinal helminth detected was Ancylostoma duodenale (n = 5, 3.84%), followed by Ascaris lumbricoides, Taenia sp. and Trichuris trichiura (n = 2 for each species, 1.5%). For intestinal protozoa, the coccidian Cryptosporidium parvum (n = 25, 19.23%) was the most common followed by Entamoeba histolytica/dispar (n = 21, 16.15%), Giardia lamblia (n = 15, 11.54%), Entamoeba coli (n = 5, 3.85%) and Blastocystis hominis (n = 3, 2.30%). The prevalence of intestinal parasitic infections in females was significantly higher than in males (P < 0.05). This is the first study highlighting that intestinal parasites are still an important public health problem in Northwestern Saudi Arabia. Therefore, health education would be the best way to prevent from intestinal parasite infections which are mainly food borne diseases.

Background: Culicoides (Diptera: Ceratopogonidae) species are known to be the vectors of Bluetongue virus and African Horses Sickness virus (AHSV) in different areas of the world. Nevertheless, other researchers have hypothesized that these arthropods could be involved in the transmission of other pathogens such as Schmallenberg virus, Plasmodium and Leishmania parasites. Identification of the Culicoides’ potential vector competence is crucial in understanding the worldwide Culicoides/Leishmania life cycle. Findings: Blood fed and parous females of biting midges Culicoides spp. were collected between 2009 and 2010 in Central Tunisia. DNA was extracted from individual blood fed Culicoides and used as a template in a genus-specific PCR. Leishmania DNA was detected in 14 Culicoides imicola specimens and one Culicoides circumscriptus. In a second step, parasite identification was performed based on a single copy Topo-isomerase II gene specific amplification and sequencing. Leishmania infantum was identified in two infected Culicoides spp. Conclusion: This is the first report of Leishmania DNA detection from naturally infected wild caught Culicoides spp. Our finding supports the assumption that Culicoides spp. are a potential vector for L. infantum.

Cutaneous leishmaniasis (CL) is a vector-borne disease transmitted by the bite of an infected sand fly. This disease is highly prevalent in Saudi Arabia where Leishmania major and L. tropica are the etiological agents. In the region of Hail, northwestern of Saudi Arabia, the incidence is about 183 cases/year. However, the epidemiology of the disease in this area is not well understood. Thus, an epidemiological survey was conducted in 2015–2016 to identify the circulating parasite and the sand fly fauna in the region of Hail. Skin lesion scrapings were collected from suspected patients with CL. The diagnosis was made by microscopic examination of Giemsa-stained smear and PCR. The parasite was identified by PCR and sequencing of the single copy putative translation initiation factor alpha subunit gene. Sand fly specimens were collected and identified morphologically. Total DNA was extracted from the abdomen of female specimens and Leishmania DNA was detected by PCR. Among the 57 examined patients, 37 were positive for CL. The identification of the parasite has revealed the single species Leishmania major. The 384 sand flies were collected belonged to two genera (Phlebotomus and Sergentomyia), six sub-genera and six species. Phlebotomus papatasi, Ph. kazeruni and Sergentomyia clydei were the dominant species. Leishmania DNA was detected in two females of Ph. papatasi two of Ph. kazeruni and one specimen of Sergentomyia clydei. Leishmania major is confirmed to be the etiological agent of cutaneous leishmaniasis in northwestern Saudi Arabia. The molecular detection of Leishmania DNA in Ph. papatasi and Ph. kazeruni supports the potential role of these two species in the transmission of Leishmania. Further epidemiological studies are needed to prove their role and to evaluate the burden of CL in the study region.

The first three documented cases of anthroponotic cutaneous leishmaniasis due to Leishmania killicki are reported from locations outside the original focus of Tataouine in southeast Tunisia. Three strains were isolated from three patients from Gafsa, Sidi Bouzid and Seliana indicating an extension of this parasite's range towards the centre and the north of Tunisia.