Molecular epidemiology of human cutaneous leishmaniasis in Jericho and its vicinity in Palestine from 1994 to 2015.

Cutaneous leishmaniases (CL) are vector-borne parasitic diseases endemic in many countries of the Middle East including Palestine. Between 1994 and 2015, 2160 clinically suspected human cases of CL from the Jericho District were examined. Stained skin tissue smears and aspirates were checked by microscopy and cultured for promastigotes, respectively. For leishmanial species identification, amplification products from a PCR-ITS1 followed by RFLP analysis using Hae III. Data were analyzed using Epi Info free-software. The overall infection rate was 41.4% (895/2160), 56.3% (504/895) of the cases were male, 43.7% (391/895) female, 60.5% (514/849) children under age 14, 41.3% (259/627) of the cases were caused by Leishmaniamajor and 57.3% (359/627) by Leishmaniatropica. The case numbers peaked in 1995, 2001, 2004, and 2012. Statistically-significant clusters of cases caused by L. major were restricted to the Jericho District; those caused by L. tropica were from the districts of Jericho, Bethlehem, Nablus and Tubas. CL is seasonal and trails the sand fly season. Distribution of cases was parabolic with fewest in July. The monthly total number of cases of CL and just those caused by L. major correlated significantly with temperature, rainfall, relative humidity, evaporation, wind speed and sunshine (P<0.05, r2=0.7-0.9 and P<0.05, r2=0.5-0.8, respectively). Cases caused by L. tropica, significantly, had a single lesion compared to cases caused by L. major (P=0.0001), which, significantly, had multiple lesions (P=0.0001). This and previous studies showed that CL is present in all Palestinian districts. The surveillance of CL has increased public awareness and molecular biological methodology for leishmanial species identification is an essential addition to classical diagnosis. The overall results are discussed, correlated to climatic and environmental changes and large-scale human activities.

The recent emergence of Leishmania tropica in Jericho (A'riha) and its environs, a classical focus of L. major.

Between 1997 and 2002, 49 strains of Leishmania were isolated from the cutaneous lesions of Palestinians living in and around Jericho. A polymerase chain reaction (PCR) amplifying the ribosomal internal transcribed spacer 1 (ITS1-PCR) was applied to their cultured promastigotes and to 207 individuals' skin scrapings spotted on filter-papers, 107 of which proved positive for leishmanial DNA. Species identification was performed by restricting the ITS1-PCR amplification products from the cultured promastigotes and the amastigotes in the scrapings with the endonuclease HaeIII. Of the 49 cultures, 28 (57%) were L. major and 21 (43%) were L. tropica. Of the 107 dermal samples tested directly, 53 (49.5%) were infected with L. major, 52 (48.5%) with L. tropica and two remained unidentified. This is the first time L. tropica has been exposed in the population of the Jericho area and on such a large scale. The itinerant behaviour of some of this population precludes categorically declaring that L. tropica has recently become established in this classical focus of L. major. For this and although 88.2% of the cases of L. tropica claimed not to have travelled out of the vicinity of Jericho, local infected sand fly vectors of L. tropica must be caught, identified and, if possible, shown to harbour infections, and, if one exists, an animal reservoir host should also be exposed to endorse whether the cases caused by L. tropica were imported or autochthonous.

Familial and environmental determinants for wheezing and asthma in a case-control study of school children in Palestine.

BACKGROUND: Our prevalence study on Palestinian school children aged 6-12 years showed lower rates for asthma and asthma symptoms than economically developed and industrialized countries. Reasons for such differences are largely unknown, and could possibly be related to different environmental and lifestyle factors. OBJECTIVE: To investigate familial, early life exposures and indoor environmental determinants for asthma in children in Palestine. METHODS: From the population of our previous study, a group of 273 children with wheeze in the past 12 months (of whom 99 children had physician-diagnosed asthma) were matched with an equal number of non-wheezing controls. This case-control study involved a parental questionnaire; skin prick testing (SPT) with mixed house dust mites, cat and dog dander, mixed grass, mixed trees pollen, Alternaria tenuis, olive tree and cockroach extracts; and serum for total and specific IgE for the same eight allergens. RESULTS: Paternal asthma and maternal hayfever significantly tripled the risk for their children to have wheezing. Previous diagnoses of bronchial allergy, bronchitis, pneumonia, or whooping cough, and positive SPT for house dust mites and cockroaches were significantly more likely among wheezing and asthmatic children than controls. Specific IgE levels for house dust mites and cat allergens showed significantly higher risk for reported wheezing. After adjustment for several environmental and sociodemographic factors using multivariate logistic regression analysis, paternal asthma, maternal hayfever, damp houses, cat and cockroach SPT positivity proved to be strong predictors for wheezing symptoms. CONCLUSION: Our study confirmed that familial 'atopic' diseases are significant predictors of childhood asthma in Palestinian children. Moreover, indoor environment such as presence of cats and domestic moulds also appear to play a role. Our findings are consistent with studies in Canada, New Zealand, Estonia and Sweden, and show promise to explore further gene-environment interaction in the genesis of asthma.

Epidemiology of cutaneous leishmaniasis in the endemic area of Jericho, Palestine.

This study of cutaneous leishmaniasis in Jericho city and the adjacent Aqbat-Jaber refugee camp investigated the seroprevalance of Leishmania major and the risk factors associated with acquiring the disease. Clinical and parasitology identification of cases showed children and young men were more affected, with the head most affected in children. Enzyme-linked immunosorbent assay (ELISA) was used to test sera from 190 individuals. The overall seroprevalence of cutaneous leishmaniasis was 26.3%. A case-control study of 247 individual in 37 households showed that a higher level of education of the head of the household and having children sleep under bed nets were significantly related to a lower incidence of cutaneous leishmaniasis.

Antigliadin antibodies detected by enzyme-linked immunosorbent assay as a marker of childhood celiac disease.

Using an enzyme-linked immunosorbent assay (ELISA) assay, we studied the sera of 17 patients with celiac disease and 114 control subjects for the levels of IgG and IgA antigliadin antibodies. As a group, the patients with celiac disease had significantly higher levels of antigliadin antibodies of both IgG and IgA classes (p less than or equal to 0.001). However, there was a significant overlap of values, resulting in respective sensitivities and specificities of 88% and 90% for IgG antigliadin antibodies, and 73% and 65% for IgA antigliadin antibodies. The combined use of both IgG and IgA antigliadin antibody levels produced a sensitivity of 86% and a specificity of 90%. A gluten-free diet in celiac patients did not seem to affect these results. We conclude that the antigliadin antibody ELISA assay cannot be used as a definitive diagnostic test for celiac disease. The small-bowel biopsy remains the principal diagnostic method; the ELISA assay should, at best, be considered a screening test for this disease.

Identification of IgA subclasses in skin of dermatitis herpetiformis patients.

There is a controversy as to the origin and to the subclass of IgA in dermatitis herpetiformis (DH) skin. The present study was undertaken to reexamine the subclasses of IgA and the presence of J-chain in biopsies of DH patients. Skin biopsies from 12 DH patients were examined for IgA, its subclasses and for J-chain by a modified direct immunofluorescence (IF) method. All DH skin biopsies were positive for IgA. Ten of the twelve biopsies were positive for IgA1. IgA2 was detected in only 3 cases, notably in those which gave the strongest IgA reactions. In general, the fluorescent staining intensity for IgA2 was weaker than IgA1 and IgA1 was less than the total IgA. This may be due to differences in the concentrations of the immunoglobulin subclasses in the skin and may also be due to the restricted specificity of antisera used in the study. Direct IF studies of the presence of J-chain yielded negative findings in all DH cases examined including those which were positive for IgA2. The higher frequency of IgA1 over that of IgA2 and the absence of J-chain indicate that the IgA immune deposits in the DH skin may not necessarily be of mucosal origin.