11 research outputs found

    Herpes Simplex Virus Type 2 Seroprevalence among Different National Populations of Middle East and North African Men

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    © 2018 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Sexually Transmitted Diseases Association. Background There are limited data on herpes simplex virus type 2 (HSV-2) seroprevalence in the Middle East and North Africa (MENA). We examined country- and age-specific HSV-2 seroprevalence among select MENA populations residing in Qatar. Methods Sera were collected from male blood donors attending Hamad Medical Corporation between June 2013 and June 2016. Specimens were screened for anti-HSV-2 IgG antibodies following a 2-test algorithm: HerpeSelect 2 ELISA was used to identify HSV-2-positive specimens, and Euroline-WB was used to confirm positive and equivocal specimens for final HSV-2 status. Trends and associations with HSV-2 seropositivity were assessed. Results Of the 2077 tested sera, 61 were found and confirmed positive. The proportion of those confirmed positive increased steadily with HerpeSelect 2 ELISA index value, ranging from 16.3% for index values of 1.101 to 1.999 to 92.9% for index values of 4 or greater. Nationality-specific seroprevalence was 6.0% (95% confidence interval [CI], 4.1%-8.8%) in Qataris, 5.3% (95% CI, 2.5%-11.1%) in Iranians, 4.2% (95% CI, 1.8%-9.5%) in Lebanese, 3.1% (95% CI, 1.2%-7.7%) in Sudanese, 3.0% (95% CI, 1.4%-6.4%) in Palestinians, 2.2% (95% CI, 1.1%-4.3%) in Egyptians, 2.0% (95% CI, 1.0%-5.0%) in Syrians, 1.0% (95% CI, 0.3%-3.6%) in Jordanians, 0.7% (95% CI, 0.1%-3.7%) in Yemenis, and 0.5% (95% CI, 0.1%-2.8%) in Pakistanis. There was evidence for higher seroprevalence in older age groups. Conclusions The seroprevalence of HSV-2 was in the range of few percentage points. There were no major differences in seroprevalence by nationality. These findings add to our understanding of HSV-2 epidemiology in MENA and indicate unmet needs for sexual health and control of sexually transmitted infections.Funding text #1 From the *Infectious Disease Epidemiology Group, Weill Cornell Medicine—Qatar, Cornell University, Qatar Foundation—Education City; †Department of Biomedical Science, College of Health Sciences, and ‡BioMedical Research Center, Qatar University, Doha, Qatar; and §Department of Healthcare Policy and Research, Weill Cornell Medi-cine, Cornell University, Ithaca, NY Acknowledgments: The authors gratefully acknowledge the administrative support of Ms Adona Canlas. They are also grateful to Dr Asmaa Al-Marwani, Ms Maria Samatti, and Ms Sana Abohasera for their work on blood specimen collection. The authors are further grateful for sup-port provided by the Biostatistics, Epidemiology, and Biomathematics Research Core at Weill Cornell Medicine—Qatar. Funding text #2 Funding: Testing kits were provided through pilot funding by the Biomedical Research Program at Weill Cornell Medicine—Qatar. Funding text #3 G.K.N. acknowledges support by Qatar University internal grant No. QUST-CHS-SPR-15/16-7. L.J.A. and S.R.D. acknowledge study conception and design support through NPRP grant number 9-040-3-008 from the Qatar National Research Fund (a member of Qatar Foundation), and G.K.N. acknowledges support from the Qatar National Research Fund UREP grant number UREP18-001-3-001. The findings achieved herein are solely the responsibility of the authors

    Performance evaluation of four type-specific commercial assays for detection of herpes simplex virus type 1 antibodies in a Middle East and North Africa population.

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    The number of diagnostic assays for the detection of herpes simplex virus type 1 (HSV-1) antibodies has increased over the years. However, their performance characteristics could vary among global populations. To investigate performance of two commercial ELISA kits, HerpeSelect1 ELISA and Euroimmun Anti-HSV-1 (gC1) ELISA (IgG); and two commercial immunoblot (IB)/Western blot (WB) assays, HerpeSelect1 and 2 Immunoblot IgG, and Euroimmun Anti-HSV-1/HSV-2 gG2 Euroline-WB (IgG/IgM); in detecting HSV-1 antibodies in a Middle East and North Africa (MENA) population. Blood specimens were collected from blood donors in Doha, Qatar, June 2013-2016. Twenty specimens were randomly selected from 10 MENA nationalities (Egypt, Iran, Jordan, Lebanon, Pakistan, Palestine, Qatar, Sudan, Syria, and Yemen; total = 200), and tested for HSV-1 antibodies. Across all six comparisons between assays, positive percent agreement ranged between 95.7% (95% CI: 91.4-98.3%) and 100.0% (95% CI: 97.8-100.0%). Negative percent agreement ranged between 86.2% (95% CI: 68.3-96.1%) and 96.2% (95% CI: 80.4-99.9%). Overall percent agreement ranged between 95.7% (95% CI: 91.7-97.8%) and 99.4% (95% CI: 96.7-99.9%). Cohen's kappa statistic ranged between 0.84 (95% CI: 0.73-0.95) and 0.98 (95% CI: 0.93-1.00). Compared against IB/WB, HerpeSelectand Euroimmun had sensitivities and specificities >96% and >86%, respectively. Positive and negative predictive values were >97% and >83%, respectively. The assays showed excellent concordance with one another, and with a high kappa statistic. The ELISA kits demonstrated robust diagnostic performance compared to the IB/WB assays. These findings support the assays' utility in clinical diagnosis and research in MENA populations

    Visible Light Photocatalytic Activity of Ag/WO3 Nanoparticles and its Antibacterial Activity Under Ambient Light and in The Dark

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    Nanomaterial such as metals and metal oxide photocatalysts have emerged as important tools for removing contaminants from wastewater and as antibacterial agents to prevent infections; this is mainly due to their stability under different irradiation conditions. Herein, the catalytic and antimicrobial activities of nanocrystalline silver (Ag), supported on tungsten oxide (WO3) nanoparticles prepared using the deposition-precipitation synthesis technique, are studied. The synthesized material was characterized as XRD, XPS, TEM, and TEM-EDS to investigate their physio-chemical properties. HRTEM, XPS analysis shows that the photocatalyst has a large sheet-like morphology with well-dispersed small metallic Ag particles (<3 nm) on the WO3 nanoparticle's surface, with most particles near the edges. Ultraviolet–visible spectra analysis observed a large redshift in the absorbing band edge and decreased bandgap energy from 2.6 to 2.1 eV. Photocatalytic analysis at different concentrations of 1% Ag/WO3 under visible light indicated a high degradation efficiency. The largest degradation efficiency of Methylene Blue (MB) under visible light irradiation was (∼80%) in 120 min at 1 g/L catalyst dosage. The photodegradation of MB under visible light as a function of catalyst dose followed the pseudo-first-order kinetics. In addition, the catalyst shows high degradation efficiency and significant dose-dependent inhibition of Gram-negative E. Coli and the Gram-positive S. aureus. Furthermore, the catalyst showed excellent stability and recyclability

    Screening the growth inhibition mechanism of sulfate reducing bacteria by chitosan/lignosulfonate nanocomposite (CS@LS) in seawater media

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    Sulfate-reducing bacteria (SRBs) induced biofilm formation is a global industrial concern due to its role in the development of microbial-induced corrosion (MIC). Herein, we have developed a biodegradable chitosan/lignosulfonate nanocomposite (CS@LS) as an efficient green biocide for the inhibition of SRBs biofilms. We investigated in detail the inhibition mechanism of SRBs by CS@LS in seawater media. Stable CS@LS-1:1 with 150–200 nm average size, and zeta potential of + 34.25 mV was synthesized. The biocidal performance of CS@LS was evaluated by sulfate reduction profiles coupled with analysis of extracted extracellular polymeric substances (EPS) and lactate dehydrogenase (LDH) release assays. As the nanocomposite concentration was increased from 50 to 500 µg/mL, the specific sulfate reduction rate (SSRR) decreased from 0.278 to 0.036 g-sulfate/g-VSS*day showing a relative sulfate reduction inhibition of 86.64% as compared to that of control. Similarly, the specific organic uptake rate (SOUR) decreased from 0.082 to 0.039 0.036 g-TOC/g-VSS*day giving a relative co-substrate oxidation inhibition of 52.19% as compared to that of control. The SRBs spiked with 500 µg/mL CS@LS showed a reduction in cell viability to 1.5 × 106 MPN/mL. To assess the biosafety of the nanocomposite on the marine biota, the 72-hours acute toxicity assays using zebrafish embryo model revealed that the LC50 for the CS@LS was 103.3 µg/mL. Thus, CS@LS can be classified as environment friendly. The nanocomposite showed long-term stability and excellent antibacterial properties against SRBs growth and is thus potentially useful for combating the problems of biofilm growth in harsh marine and aquatic environments.The authors are grateful for the financial support from NPRP grant (NPRP8-286-02-118) from the Qatar National Research Fund (a member of Qatar Foundation). The findings achieved herein are solely the responsibility of the authors. The authors are thankful to J. Ponraj, M Helal, and M. Pasha at the Core lab of QEERI/HBKU, Doha, Qatar for TEM and SEM analysis, respectively. Open Access funding provided by the Qatar National Library

    Low risk of serological cross-reactivity between the dengue virus and SARS-CoV-2 IgG antibodies using advanced detection assays.

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    Several studies have reported serological cross-reactivity of the immune responses between SARS-CoV-2 and DENV. Most of the available studies are based on the point of care (POC) rapid testing kits. However, some rapid test kits have low specificity and can generate false positives. Hence, we aimed to investigate the potential serological cross-reactivity between SARS-CoV-2 and DENV IgG antibodies using advanced assays including chemiluminescence immunoassay (CLIA) and ELISA test. A total of 90 DENV-IgG-ELISA positive and 90 negative pre-pandemic sera were tested for anti-SARS-CoV-2-IgG using the automated CL-900i CLIA assay. Furthermore, a total of 91 SARS-CoV-2-IgG-CLIA positive and 91 negative post-pandemic sera were tested for anti-DENV-IgG using the Novalisa ELISA assay. The DENV-IgG positive sera resulted in five positives and 85 negatives for SARS-CoV-2-IgG. Similarly, the DENV-IgG negative sera also resulted in five positives and 85 negatives for SARS-CoV-2-IgG. No statistically significant difference in specificity between the DENV-IgG positive and DENV-IgG negative sera was found (p-value=1.00). The SARS-CoV-2-IgG positive sera displayed 43 positives, 47 negatives, and one equivocal for DENV-IgG. Whereas the SARS-CoV-2-IgG negative sera resulted in 50 positives, 40 negatives, and one equivocal for DENV-IgG. No statistically significant difference in the proportion that is DENV-IgG positive between the SARS-CoV-2-IgG positive and SARS-CoV-2-IgG negative sera (p-value=0.58). In conclusion, there is a low risk of serological cross-reactivity between the DENV, and SARS-CoV-2 IgG antibodies when using advanced detection assays.  .L.J.A. acknowledges the support of the Biomedical Research Program and the Biostatistics, Epidemiology, and Biomathematics Research Core, both at Weill Cornell Medicine-Qatar. This work was made possible by Grant Nos. RRC-2-032 and UREP19-013-3-001 from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the authors. In addition, G.K.N. would also like to acknowledge funds from Qatar University’s internal Grant QUERG-CMED-2020-2

    Dengue and chikungunya seroprevalence among Qatari nationals and immigrants residing in Qatar.

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    The objective of this study is to characterize the seroprevalence of anti-dengue (DENV) and anti-chikungunya (CHIKV) antibodies among blood donors residing in Qatar who are Middle East and North Africa (MENA) nationals and non-nationals. Sera were collected from adult blood donors in Qatar from 2013 to 2016 and tested for anti-DENV and anti-CHIKV IgG using commercial microplate enzyme-linked immunosorbent assays. Age-specific seroprevalence was summarized by region/nationality: Asia (India, Philippines), Middle East (Iran, Jordan, Lebanon, Pakistan, Palestine, Syria, Yemen), North Africa (Egypt, Sudan), Qatar. The adjusted odds of anti-DENV and anti-CHIKV IgG seropositivity was estimated by logistic regression. Among 1,992 serum samples tested, Asian nationals had higher adjusted odds of being seropositive for anti-DENV antibodies compared to nationals of the Middle East (aOR 0.05, 95% CI 0.04-0.07), North Africa (aOR 0.14, 95% CI 0.10-0.20), and Qatar (aOR 0.01, 95% CI 0.01-0.03). Asian nationals also had higher adjusted odds of being seropositive for anti-CHIKV antibodies compared to those from the Middle East (aOR 0.14, 95% CI 0.07-0.27), North Africa (aOR 0.50, 95% CI 0.26-0.96), and Qatar (aOR 0.38, 95% CI 0.15-0.96). The adjusted odds of being anti-DENV seropositive was higher among anti-CHIKV seropositive adults, and vice versa (aOR 1.94, 95% CI 1.09-3.44), suggesting co-circulation of these viruses. DENV and CHIKV exposure is lower in Qatar and MENA nationals compared to Asian nationals suggesting a lower burden of DENV and CHIKV disease in the MENA. Antibodies to both viruses were detected in nationals from most MENA countries, supporting the need to better understand the regional epidemiology of these viruses.This work was supported by Qatar University student grants [QUST-1-CHS-2018-3/4, received by ESA, MMH, SSO, DMA, HGE] and the Qatar National Research Fund [UREP19-013-3- 001, received by LJA and GKN]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    Effect of Water-Pipe Smoking on the Normal Development of Zebrafish

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    Background: Among all types of tobacco consumption,Water-Pipe Smoking (WPS) is the most widely used in the Middle East and second-most in several other countries. The effect of WPS on normal development is not yet fully understood, thus the aim of this study is to explore the acute toxicity effects of WPS extract on zebrafish larvae. Methods: In this study, we compared the effects of WPS smoke condensates at concentrations varying from 50 to 200 g/mL on developmental, cardiac, and behavioural (neurotoxicity) functions. Gene expression patterns of cardiac biomarkers were also evaluated by RT-qPCR. Results: Exposing zebrafish embryos to 50, 100, 150 and 200 g/mL WPS for three days did not affect the normal morphology of Zebrafish embryos, as the tail flicking, behavioural and locomotion assays did not show any change. However, WPS deregulated cardiac markers including atrial natriuretic peptide (ANP/NPPA) and brain natriuretic peptide (BNP/NPPB). Furthermore, it induced apoptosis in a dose-dependent manner. Conclusion: Our data demonstrate that WPS can significantly affect specific cardiac parameters during the normal development of zebrafish. Further investigations are necessary to elucidate the pathogenic outcome of WPS on different aspects of human life, including pregnancy.This research was funded by Qatar University -internal grants, grant numbers QUCP-CHS-2019-1, IRCC-2021-013 and Qatar Petroleum under project number QUEX-BRC-QP-PW-18/19. The findings achieved herein are solely the responsibility of the authors

    Seroprevalence of hepatitis E virus among blood donors in Qatar (2013-2016)

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    BACKGROUND Hepatitis E virus (HEV) is an RNA virus transmitted mainly through zoonotic transmission or fecal–oral route. More than 80% of Qatar's population are expatriates, including many coming from hyperendemic countries; thus, it is important to estimate the seroprevalence and to compare between different nationalities. The results can be useful in alerting blood banks to the importance of HEV screening. STUDY DESIGN AND METHODS Samples from 5854 blood donations provided by Hamad Medical Corporation were tested in the period between June 2013 to June 2016. Samples were tested for the presence of anti-HEV immunoglobulin (Ig)G and IgM antibodies and viral RNA using real-time polymerase chain reaction (PCR). Descriptive statistics, bivariate analysis, and multivariate logistic regression were used. RESULTS Anti-HEV seroprevalence was 20.7%. A total of 1198 and 38 donations tested positive for IgG and IgM antibodies, respectively. Of the IgM-positive donations four tested positive by PCR. A significant association was detected between HEV seroprevalence with age and nationality. CONCLUSION The seroprevalence of anti-HEV was high in Qatar. Since HEV IgM and RNA were detected, this suggests the possibility of HEV transmission by transfusion. Blood banks in Qatar and the region should consider screening for HEV, especially when transfusion is intended to pregnant women or immunocompromised patients.This report was made possible by UREP grant # UREP19-013-3-001 from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the author(s). The authors declare no conflict of interest

    The prevalence of HEV among non-A-C hepatitis in Qatar and efficiency of serological markers for the diagnosis of hepatitis E

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    Abstract Background The rapid growth of Qatar in the last two decades has attracted a large influx of immigrant workers who mostly come from HEV-hyperendemic countries. Thus, we aim to investigate the prevalence of HEV among acute non-A-C hepatitis patients in Qatar; and to evaluate the performance of four dominant commercial serological assays for HEV diagnosis. Methods 259 patients with non-A-C hepatitis were tested using the Wantai HEV-IgM, HEV-IgG, HEV-Ag ELISA kits, and the MP Biomedical HEV-Total Ab ELISA kit. ALT levels were tested and HEV RNA (viral loads) was performed using Taqman AmpliCube HEV RT-PCR kit (Mikrogen, Neuried, Germany). The performance of each kit was assessed according to the RT-PCR results. Results HEV-RNA was detected in 23.1% of the samples. Most of these HEV-RNA-positive cases belonged to non-Qatari residents from the Indian subcontinent; India, Pakistan, etc. HEV-Ag, HEV-IgM, HEV-IgG, HEV-Total Ab were detected in 5.56%, 8.65%, 32.1%, and 34.2% of all tested samples, respectively. Elevated ALT levels were highly correlated with the HEV-Ag, HEV-IgM, HEV-RNA but not with the HEV-IgG and HEV-Total Ab. Although HEV-Ag was very specific (100%), yet its sensitivity was poor (36.7%). HEV-IgM demonstrated the best second marker for diagnosis of acute HEV after RT-PCR as jugged by the overall performance parameters: specificity (96.2%), sensitivity (71.4%), PPV (83.3%), NPP (92.7%), agreement with RT-PCR (91.0%), and Kappa-value (0.71). Conclusion Our study demonstrated a high prevalence of HEV virus in Qatar, mostly among immigrants from the Indian subcontinent. The HEV-IgM represents the best marker for detecting the acute HEV infection, where RT-PCR cannot be performed

    Performance evaluation of five commercial assays in assessing seroprevalence of HEV antibodies among blood donors

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    Although hepatitis E virus (HEV) is mainly transmitted via the faecal-oral route, the rate of HEV transmission via blood donation is on the rise. However, the seroprevalence of HEV among blood donors is not well established and is thought to be affected by the type of diagnostic assay used. We aimed to evaluate performance and correlation among widely used commercial diagnostic assays for the seroprevalence assessment of HEV-IgM/IgG among blood donors. A total of 1049 blood donor samples were tested for HEV IgG and IgM using different enzyme immunoassays (Wantai, Eruoimmune, MP diagnostics, Mikrogen immunoblot, HEV-IgM rapid test). The performance of each assay was evaluated according to our established silver standard value based on three or more IgG concordant assay results. HEV seroprevalence varied considerably using these assays, ranging from 10.1 % (Euroimmune-ELISA) to 18.0 % (Wanti-ELISA) for HEV-IgG, and from 0.2 % (Wanti-ELISA) to 2.6 % (MP Rapid test) for HEV-IgM. A total of 155 of 216 (71.6%) samples tested positive for HEV-IgG by three or more concordant assays. On the other hand, IgM assays showed poor agreement as only 7.6 % (4/52) of the specimens were positive according to three or more concordant assay test results. All HEV-IgG assays revealed high sensitivity and specificity (ranging 96.5-100 %),and excellent Kappa concordance (0.88-0.95), except for Euroimmun ELISA (sensitivity=61.5 %, kappa=0.63). MP ELISA showed the highest levels of sensitivity (100 %) and specificity (98.5 %). Due to discrepancies in the performance of various IgG and IgM assays, seroprevalence studies should be based on furher confirmatory testing for decisive conclusions to be reached
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