Kamal Dumaidi

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.

Incidence of Echinococcus granulosus in Domestic Dogs in Palestine as Revealed by Copro-PCR.

Hydatidosis or echinococcosisis considered a neglected zoonotic disease despite its high burden in the livestock industry and the high risk of infection by humans in endemic areas. In a cross-sectional study we estimated the copro-Incidence and also genotyped Echinococcus granulosus isolates from domestic dogs using polymerase chain reaction (PCR). Medical archives in nine major hospitals in Palestine were reviewed to determine incidence of E. granulosus infection detected in humans during surgery. Faecal samples were collected from 93 domestic dogs in three districts with the highest number of human cases: Al-Khalil (Hebron), Tubas and Jenin. Genomic DNA was extracted from dog faecal samples and amplified by PCR targeting the repeat DNA sequence (EgG1 Hae III) followed by sequencing of five positive samples. Genotyping was determined by sequencing and BLAST searching of mitochondrial cytochrome c oxidase subunit (CO1). The incidence of E. granulosus infection detected in humans at surgery was 1.2 per 100,000 in the West Bank and 1.0 per 100,000 in Gaza Strip. Seventeen of 93 domestic dogs (18%) were positive, based upon comparison with the Echinococcus DNA control. The five sequenced samples were confirmed to be E. granulosus. Successfully genotyped sample belonged to E.granulosus sensu stricto (formerly G1-G3 complex, sheep strain). For domestic dogs, age group (13-24 months) and sex were identified as two risk factors for contracting E. granulosus. The study identified the high incidence of E. granulosus sensu stricto in dogs in Palestine.

Prevalence of occult HBV among hemodialysis patients in two districts in the northern part of the West Bank, Palestine

Occult hepatitis B infection is the case with undetectable HBsAg, but positive for HBV DNA in liver tissue and/or serum. Occult hepatitis B infection among hemodialysis patients in Palestine has been understudied. In this study, 148 hemodialysis patients from 2 northern districts in Palestine, Jenin (89) and Tulkarem (59), were investigated for occult hepatitis B, HBV, HCV infections with related risk factors. ELISA and PCR were used for the detection of anti‐HBc and viral DNA, respectively. The overall prevalence of occult hepatitis B infection among the study group was 12.5% (16/128). Occult hepatitis B infection is more prevalent among males with most cases (15/16) from Jenin District. About one‐third (42/132) of the hemodialysis patients were anti‐HBc positive. Approximately 27% of the hemodialysis patients were infected with HCV. Around 20% (28/140) were positive for HBV DNA, but only 8.2% (12/146) of the hemodialysis patients were positive for HBsAg. The comparison between hemodialysis patients with occult hepatitis B infection and those without occult hepatitis B infection for selected risk factors and parameters as liver Enzyme, age, sex, HCV infection, blood transfusion, kidney transplant, anti‐HBc, and vaccination showed no statistical significance between both categories. Duration of hemodialysis significantly affected the rate of HCV infection. HCV is significantly higher in hemodialysis patients with both Diabetes mellitus and hypertension. The prevalence of occult hepatitis B infection among hemodialysis patients is high; requiring stringent control policies. HBsAg assay is insufficient test for accurate diagnosis of HBV infection among hemodialysis patients. J. Med. Virol. 86: 1694–1699, 2014.

The clinical burden of human cystic echinococcosis in Palestine, 2010-2015

Background Cystic echinococcosis (CE) is classified by the WHO as a neglected disease inflicting economic losses on the health systems of many countries worldwide. The aim of this case-series study was to investigate the burden of human CE in Palestine during the period between 2010 and 2015. Methodology/Principal findings Records of surgically confirmed CE patients from 13 public and private hospitals in the West Bank and Gaza Strip were reviewed. Patients’ cysts were collected from surgical wards and formalin-fixed paraffin-embedded (FFPE) blocks were collected from histopathology departments. Molecular identification of CE species /genotypes was conducted by targeting a repeat DNA sequence (EgG1 Hae III) within Echinococcus nuclear genome and a fragment within the mitochondrial cytochrome c oxidase subunit 1, (CO1). Confirmation of CE species/genotypes was carried out using sequencing followed by BLAST analysis and the construction of maximum likelihood consensus dendrogram. CE cases were map-spotted and statistically significant foci identified by spatial analysis. A total of 353 CE patients were identified in 108 localities from the West Bank and Gaza Strip. The average surgical incidence in the West Bank was 2.1 per 100,000. Spot-mapping and purely spatial analysis showed 13 out of 16 Palestinian districts had cases of CE, of which 9 were in the West Bank and 4 in Gaza Strip. Al-Khalil and Bethlehem were statistically significant foci of CE in Palestine with a six-year average incidence of 4.2 and 3.7 per 100,000, respectively. Conclusions/Significance To the best of our knowledge, this is the first confirmation of human CE causative agent in Palestine. This study revealed that E. granulosus sensu stricto (s.s.) was the predominating species responsible for CE in humans with 11 samples identified as G1 genotype and 2 as G3 genotype. This study emphasizes the need for a stringent surveillance system and risk assessment studies in the rural areas of high incidence as a prerequisite for control measures.

Persistence of Anti-HBs Among Palestinian Medical Students After 18 - 22 Years of Vaccination: A Cross-Sectional Study

Background: Hepatitis B infection is a global public health problem affecting various sectors in the society. Vaccination is the first line measure to prevent the disease. Objectives: To assess the persistence of anti-HBs marker among medical students after 18 - 22 of vaccination as an indicator for Hepatitis B virus vaccine efficacy. Patients and Methods: In this study, 249 Palestinian medical students vaccinated at birth, 1, and 6 months of age using Engerix™-B starting from 1992 were studied. About 58% (144/249) of the students were Palestinians holding Israeli citizenship, while 42% (105/249) were Palestinians from the West Bank. Students were tested serologically for anti-HBs, as a marker for vaccine-induced immunity. Results: Over 75% (188/248) of students had levels of anti-HBs greater than 10 mIU/mL indicating immunity and protection. Five cases had positive results for anti-HBc indicating exposure to HBV infection; however, none of these cases showed any sign of HBV-DNA indicating effective clearance of the virus by the vaccine. Around 57% of the study group had anti-HBs level of 100 - 1000 mIU/mL. No significant association was found between anti-HBs level and age, sex, locality and level of anti-HBc (P > 0.05). The students were aware of different aspects of hepatitis B infection regarding the virus, symptoms, prevention and mode of transmission. Conclusions: The Palestinian and Israeli official policies to give a booster dose for risk groups like medical students at anti-HBs level below 10 mIU/mL should continue to ensure absolute protection. The currently-used vaccine and its time program cleared virus from students believed to have been exposed to the virus during their lifetime.

Genetic diversity of the enteroviruses detected from Cerebrospinal fluid (CSF) samples of patients with suspected aseptic meningitis in northern West Bank, Palestine in 2017

BACKGROUND: Human enterovirus genus showed a wide range of genetic diversity. OBJECTIVES: To investigate the genetic diversity of the enteroviruses isolated in 2017 in northern West Bank, Palestine. STUDY DESIGN: 249 CSF samples from aseptic meningitis cases were investigated for HEV using two RT-PCR protocols targeting the 59 NCR and the VP1 region of the HEV genome. The phylogenetic characterization of the sequenced VP1 region of Echovirus18 (E18) and CoxsackievirusB5 (CVB5) isolated in Palestine along with 27 E18 and 27 CVB5 sequences available from the Genbank were described. RESULTS: E18 and CVB5 account for 50% and 35% of the successfully HEV types, respectively. Phylogenetic tree of E18 and CVB5 showed three main clusters, with all Palestinian isolates uniquely clustering together with those from China and from different countries, respectively. Cluster I of E18, with 13 Palestinian and 6 Chinese isolates, showed the lowest haplotype-to-sequence ratio (0.6:1), haplotype diversity (Hd), nucleotide diversity (π), and number of segregating sites (S) compared to clusters II and III. Furthermore, cluster I showed negative Tajima9s D and Fu-Li9sF tests with statistically significant departure from neutrality (P

A comparison of the efficiency of three sampling methods for use in the molecular and conventional diagnosis of cutaneous leishmaniasis

In human cutaneous leishmaniasis (CL), the success of positive diagnoses and species identifications depends, primarily, on how biopsies are taken and then processed and examined. The efficiency of three methods of taking skin biopsies from suspect cases of CL was compared using the classical methods of microscopy of stained smears, in vitro culture of tissue aspirate, and internal transcribed spacer region 1 (ITS1)-polymerase chain reaction in diagnosing positive cases and identifying the species of Leishmania causing them. From 1994-2014, biopsy samples from the skin lesions of 2232 CL-suspected patients were collected as unstained smears, as smears stained with Giemsas stain and on filter paper, and compared in the diagnostic tests employed. Matched comparison based on testing biopsy samples from 100 patients, microscopy, in vitro culture and ITS1-PCR were also conducted to assess the most suitable combination of methods for diagnosing leishmaniases. In the 100-case-matched comparison, the three different types of sample proved to be equally good with no significant difference (P > 0.05). However, skin tissue imprints on filter paper revealed most cases of CL. The kappa statistic for measuring the degree of agreement among the three samples was 89%, which is considered good. Agreement was highest between imprints on filter paper and unstained smears, and lowest was for stained smears. In the overall comparison between the ITS1-PCR and conventional methods, the ITS1-PCR using samples from filter papers was the most sensitive method but the difference was insignificant (P = 0.32). The combination of microscopy together with ITS1-PCR on samples from filter papers increased the sensitivity significantly to 46%, compared to using the methods individually (P = 0.003-0.0008). On comparing the results of the tests done on the samples from the 2232 patients after applying ITS1-PCRs to their samples from filter papers, unstained smears, in vitro culture, microscopy, and stained smears showed, respectively, test sensitivities of 81, 69, 64, 57 and 48%. Of the tests and samples adjudicated, ITS1-PCRs run on skin tissue samples from filter papers proved best for the routine laboratory diagnosis of CL. Adding microscopy of stained smears to it, improved its diagnostic value significantly.