Identification of Leishmania strains from Jordan.

The enzymatic profiles of 22 Jordanian Leishmania isolates obtained from humans, Psammomys obesus and Phlebotomus papatasi were determined using starch-gel electrophoresis and a 15-enzyme system. Thirteen of the isolates were typed as L. major and the other nine, all from Mediterranean or sub-Mediterranean regions, as L. tropica. The two zymodemes of L. major encountered, MON-26 and MON-103, differed in terms of purine nucleoside phosphorylase 2. The MON-26 isolates came from the Jordanian plateau whereas those of MON-103 were only collected from the Jordan valley. The four zymodemes of L. tropica observed (MON-7, MON-137, MON-200 and MON-265) were identical for only two of the 15 enzymes studied (i.e. isocitrate dehydrogenase and glucose phosphate isomerase), confirming the high level of enzymatic polymorphism of L. tropica. So far, MON-200 and MON-265 have only been found in Jordan.

Seroprevalence of West Nile, Rift Valley, and sandfly arboviruses in Hashimiah, Jordan.

We conducted a serosurvey among patients of a health center in Hashimiah, a Jordanian town of 30,000 inhabitants located near a wastewater treatment plant and its effluent channel. Serum samples from 261 patients >/=5 years of age were assessed for immunoglobulin G (IgG) and IgM antibodies against West Nile, sandfly Sicilian, sandfly Naples, and Rift Valley viruses; the seroprevalence of IgG antibodies was 8%, 47%, 30%, and 0%, respectively. Female participants were more likely to have been infected than male. Persons living within 2 km of the treatment plant were more likely to have been infected with West Nile (p=0.016) and sandfly Sicilian (p=0.010) viruses. Raising domestic animals within the house was a risk factor for sandfly Sicilian (p=0.003) but not for sandfly Naples virus (p=0.148). All serum samples were negative for IgM antibodies against the tested viruses. Our study is the first documentation of West Nile and sandfly viruses in Jordan and calls attention to the possible health hazards of living close to wastewater treatment plants and their effluent channels.

Humoral response of Meriones libycus to experimental infection with Leishmania major.

The humoral responses of laboratory-reared jirds (Meriones libycus) to inoculation with various doses of Leishmania major were determined. The animals were inoculated intradermally with 10(2), 10(3), 10(5) or 10(7) promastigotes of a strain of L. major originally isolated from a Jordanian patient. The jirds were then bled at various intervals throughout the 26 weeks of the study, and the sera checked, by IFAT, for antibodies to homologous parasites. There were no detectable humoral responses in the animals inoculated with 10(2) promastigotes each or in parasite-free controls but a positive response was apparent in each of the other jirds. The animals given 10(3) promastigotes each required 3 months to become IFAT-positive whereas those given 10(5) and 10(7) parasites only needed 4 and 2 weeks, respectively. More than 50% of the animals inoculated with 10(3) parasites each developed strongly positive sera 2 months post-infection, whereas > 50% of the animals inoculated with 10(5) or 10(7) parasites each had strongly or very strongly positive sera 4 and 2 weeks post-inoculation, respectively. The data indicate that, in M. libycus inoculated with L. major, the time required for the humoral response to develop and its intensity are both dose-related.

Visceral leishmaniasis from Bal'a, Palestine, caused by Leishmania donovani s.1. identified through polymerase chain reaction and restriction fragment length polymorphism analysis.

A 5-year old female from Bal'a, Tulkarm area, Palestine, was admitted with an 8 month history of fever, excessive night sweating, abdominal distension and enlargement, weight loss and sever anorexia. She was investigated elsewhere without reaching specific diagnosis. On admission, the history and symptoms were compatible with visceral leishmaniasis and bone marrow aspirate was positive for Leishmania amastigotes. The serum titer, using IFAT, was 1:640 for L. infantum and 1:320 for L. major promastigotes. When bone marrow material was also subjected to PCR followed by RFLP enzyme analysis, three fragments of the PCR product of the parasite present were obtained: two fragments of 260 bp and one fragment of 80 bp, identical with the pattern obtained with L. donovani. The patient received sodium stibogluconate, 200 mg IM for 30 days. Six months after treatment, the spleen was 2 cm below the costal margin, the liver was not palpable and she gained 1 kg. This case alerts general practitioners, pediatricians and health authorities to the presence of visceral leishmaniasis in Palestine and to the possibility of the disease being encountered in Jordan.

Urinary schistosomiasis contracted from an irrigation pool in Ramah, the southern Jordan Valley, Jordan.

Autochthonous cases of urinary schistosomiasis are reported for the second time in Jordan. Eight Jordanian juveniles (seven males and one female) ranging in age from 10 to 15 years were diagnosed in 1995 as having the disease. Urine examination using the membrane filtration technique showed varying intensities of infection. The patients were treated with praziquantel and a follow-up showed the passage of dead eggs in the urine of five patients one month after treatment. All had egg-negative urine three months post-treatment. Epidemiologic investigation showed that the patients did not leave Jordan and that the seven males swam frequently in 1994 in an irrigation pool present in a farm at Ramah, in the southern Jordan Valley. The female patient had frequent contact with the pool water since she often went to the farm to obtain water for domestic animals. Bulinus truncatus snails were found in the pool and in pools on other farms in the area. Two hundred snails collected from the site did not shed cercariae after six months of observation. Several foreign workers in the area were found infected with Schistosoma haematobium, suggesting they were the source of infection.

The endemicity of Leishmania tropica (zymodeme MON-137) in the Eira-Yarqa area of Salt District, Jordan.

The endemicity of cutaneous leishmaniasis (CL) caused by Leishmania tropica was ascertained in a focus of the disease around Eira and Yarqa in Salt District, Jordan. This focus is about 10 km to the east of another focus of CL, where L. major is the causative agent. As CL occurs sporadically in the study area, with nine cases diagnosed between 1993 and 1995, it is probably zoonotic. Each case had one or two lesions and most lesions were on the face. Isoenzymatic electrophoresis showed that all the parasites isolated in the Eira-Yarqa focus and identified to zymodeme level belonged to zymodeme MON-137 and therefore differed from all the L. tropica isolates identified in other regions of Jordan. Eight species of Phlebotomus (P. alexandri, P. major, P. sergenti, P. papatasi, P. perfiliewi, P. jacusieli, P. canaaniticus and P. arabicus), two members of the Sergentomyia dentata group and S. tiberiadis and S. taizi were collected in the focus, using castor-oil traps. The epidemiological significance of the sandflies collected is discussed.

A longifurcate distome cercaria from Bulinus truncatus snails in the Jordan Valley, Jordan.

Bulinus truncatus snails collected from water bodies of the South Shuna region, north of the Dead Sea, were found infected with a pharyngeal longifurcate distome cercaria. This new form of cercaria is named Cercaria bulini I. It has three pairs of penetration glands, 12 pairs of flame cells, and lacks the intestinal cecae. This cercaria is an active swimmer and develops within an elongated sporocyst. Other details on the morphology, behavior, and development of C. bulini I are presented.

Epidemiology of cutaneous leishmaniasis in Jordan: 1983-1992.

BACKGROUND: The extent of the problem of cutaneous leishmaniasis in Jordan during the decade 1983 to 1992 was investigated. METHODS: Data were collected from the dermatology departments and the laboratories of the Royal Medical Services and the Ministry of Health as well as from private dermatologists. Two thousand two hundred and ninety-five cases were verified of whom men represented 80%. The majority (80%) were < 25 years with the highest percentage (31%) occurring in the 16 to 20-year age group. RESULTS: The lowest number of cases was reported in June compared to the maximum in October, and the highest number recorded per year was 463 in 1992. For the decade, the Jordan Valley was the most important locality where 43% of the cases occurred. The incidence rate per 100,000 ranged from 1.89 in 1989 to 14.39 in 1984 and the period prevalence for the decade was 5.36 per 100,000. The time-lag between the appearance of a lesion and the first diagnosis extended from 0 to 23 months with the average being 2 months. The number of lesions per patient ranged from one to 45; 24% were located on the face, 28% on the upper extremity, 36% on the lower extremity, and 12% on other sites. CONCLUSIONS: The factors that contributed to the findings include infected rodent, nonexposed army recruits and farm workers, land reclamatory and relaxation of preventative measures.

Serodiagnosis of cutaneous leishmaniasis in Jordan using indirect fluorescent antibody test and the enzyme-linked immunosorbent assay.

The usefulness of IFAT and ELISA, in the detection of antibodies to cutaneous leishmaniasis (CL) in Jordanian cases was studied. Serum samples were collected from three groups of confirmed or putative CL patients (n = 100), 132 healthy blood donors, 10 patients with pulmonary tuberculosis (TB), and 16 patients with typhoid fever (TF). Antigens for both tests were prepared from promastigotes of a Leishmania major isolate. At a serum dilution of respectively 1:16 and 1:100 both IFAT and ELISA had a sensitivity of 81%, whereas in the healthy control group their specificities were 95 and 96%. Maximal titers in the 37 parasitologically-proven cases were 1:128 in IFAT and 1:800 in ELISA. Antibodies were detected in about 50% of the 42 cases that had negative parasitological tests but had typical lesions with IFAT-titers up to 1:64 and ELISA titers up to 1:400. However, antibodies were detected in 19% of the 21 clinically-suspected cases of CL with maximal titers of 1:32 in IFAT and 1:200 in ELISA. A variation in antibody level was detected in the treated and the non-treated patients who were followed up for few months after diagnosis. One serum specimen taken from a patient with TB and two sera taken from patients with TF cross-reacted with Leishmania antigens in both IFAT and ELISA. This false positivity could be eliminated by absorption of these sera with their homologous antigens. There was no significant relationship between antibody level and duration of infection with CL. On the other hand, a significant relationship between antibody level and number of CL lesions was found. Although both tests would be useful for detection of circulating antibodies in cases suspected of having CL, especially in those having several lesions, IFAT is recommended for use in Jordan for its simplicity and rapidity.

Rodents as reservoir hosts of cutaneous leishmaniasis in Jordan.

Rodents were collected from endemic foci of cutaneous leishmaniasis in Jordan, either by flooding their burrows with water or using Sherman traps. Of the 170 jirds (Psammomys obesus) collected, 39 (23%) had Leishmania amastigotes in one or both ears. Although cultures of ear biopsies from the infected animals were all positive, cultures made using biopsies from their noses, livers or spleens were all negative. The infected jirds were encountered in seven of the nine areas studied. Biochemical characterization of six isolates from P. obesus, using cellulose acetate electrophoresis of six enzymes (glucose-6-phosphate dehydrogenase, 6-phosphogluconic dehydrogenase, malic enzyme, phosphoglucomutase, phosphoglucoisomerase and fructokinase) showed that the jird isolates were isoenzymatically identical with two Jordanian human Leishmania isolates and reference isolates of L. major but differed from reference strains of L. tropica. None of the other rodents caught (Meriones libycus, M. crassus, M. tristrami, Allactaga euphratica and Gerbillus spp.) yielded Leishmania parasites, confirming that P. obesus is the major reservoir host of cutaneous leishmaniasis in Jordan.

Course of infection and humoral response to Leishmania major in inbred Meriones unguiculatus.

Numerous species of Meriones have been incriminated as natural reservoir hosts of Leishmania major in Mongolia, Soviet Asia, Afghanistan, the Middle East, and North Africa. However, little is known about the immunological response or course of infection in these small rodents. In this study, 40 commercially obtained inbred Meriones unguiculatus were divided into equal groups and injected in the right hind footpad with various doses of L. major promastigotes or with medium only. At regular intervals, blood was collected from the animals for subsequent evaluation of the kinetics of anti-L. major serum antibody production. Footpad lesions were measured periodically for 13 wk, beginning just before infection. The humoral response to infection and the course and severity of disease were dose related. However, metastasis lymph nodes, liver, spleen, and secondary cutaneous sites occurred at each of the doses tested.

Cutaneous leishmaniasis in Jordan: biochemical identification of human and Psammomys obesus isolates as Leishmania major.

As part of a series of epidemiological and ecological studies of leishmaniasis in Jordan, we have made functional studies of four isolates from human lesions and from ear lesions of three field-collected Psammomys obesus. Primary isolates were subcultured, frozen stabilates prepared and BALB/c mouse infectivity experiments initiated. Each mouse was inoculated with 4-8 x 10(4) promastigotes into a hind footpad. Quantitative evaluation of the footpads showed enlargement three to four weeks postinoculation. Amastigotes were readily identified in smears from footpad lesions and promastigotes in culture. At 47 days, liver and spleen samples grew out promastigotes. Biochemical characterization of these seven isolates was made by isozyme analysis using cellulose acetate membrane electrophoresis of fructokinase, phosphoglucose isomerase, phosphoglucomutase, aspartate aminotransferase, malate dehydrogenase, glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase. Reference isolates used for comparison were Leishmania major, L. tropica minor, L. donovani, L. aethiopica and L. m. mexicana. All seven Jordan isolates showed enzyme electromorphs identical to L. major, confirming our ecological/epidemiological studies that P. obesus is a major reservoir for human cutaneous leishmaniasis in Jordan.

Cutaneous leishmaniasis in Mowaqqar area, Amman Governorate, Jordan.

At least 193 cases of cutaneous leishmaniasis occurred in eight villages of Mowaqqar area, Jordan, between December 1982 and April 1983. Peak transmission of the disease is thought to have taken place in late summer 1982. Approximately 67% of the cases were below 15 years of age and the lesions seen were of the dry type. The sand jird, Psammomys obesus, and the sandfly, Phlebotomus papatasi, the potential animal reservoir and vector of the disease respectively, were found in the affected area. Furthermore, Leishmania amastigotes were seen in smears from ears of seven out of 11 jirds collected from the area suggesting the zoonotic nature of the disease there.

Intestinal cestodes of stray dogs in Jordan.

Five species of cestodes namely Echinococcus granulosus, Taenia hydatigena, Taenia pisiformis, Taenia ovis and Dipylidium caninum were recovered post mortem from 120 out of 173 stray dogs collected from the 5 governorates of Jordan during the period June 1979 to November 1980. Twenty-five of the examined dogs (14%) were found to be infected with E. granulosus, 79 (46%) with T. hydatigena, 14 (8%) with T. pisiformis and 5 (3%) with T. ovis. Dipylidium caninum was encountered in 33 (19%) of the examined dogs and infection with this parasite was significantly higher in males than in females. The parasites, except for D. caninum which was encountered in the ileum, were almost exclusively recovered from the duodenum and the jejunum. Single, double and triple infections with those cestodes were recorded.