Publications by authors named "Anwar M Hashem"

56 Publications

Nationwide Seroprevalence of SARS-CoV-2 in Saudi Arabia.

J Infect Public Health 2021 Jul 24;14(7):832-838. Epub 2021 Apr 24.

King Abdullah International Medical Research Center, Riyadh, Saudi Arabia; King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia.

Background: Estimated seroprevalence of Coronavirus Infectious Disease 2019 (COVID-19), caused by the Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) is a critical evidence for a better evaluation of the virus spread and monitoring the progress of COVID-19 pandemic in a population. In the Kingdom of Saudi Arabia (KSA), SARS-CoV-2 seroprevalence has been reported in specific regions, but an extensive nationwide study has not been reported. Here, we report a nationwide study to determine the prevalence of SARS-CoV-2 in the population of KSA during the pandemic, using serum samples from healthy blood donors, non-COVID patients and healthcare workers (HCWs) in six different regions of the kingdom, with addition samples from COVID-19 patients.

Methods: A total of 11,703 serum samples were collected from different regions of the KSA including; 5395 samples from residual healthy blood donors (D); 5877 samples from non-COVID patients collected through residual sera at clinical biochemistry labs from non-COVID patients (P); and 400 samples from consented HCWs. To determine the seroprevalence of SARS-CoV-2, all serum samples, in addition to positive control sera from RT-PCR confirmed COVID-19 patients, were subjected to in-house ELISA with a sample pooling strategy, which was further validated by testing individual samples that make up some of the pools, with a statistical estimation method to report seroprevalence estimates.

Results: Overall (combining D and P groups) seroprevalence estimate was around 11% in Saudi Arabia; and was 5.1% (Riyadh), 1.5% (Jazan), 18.4% (Qassim), 20.8% (Hail), 14.7% (ER; Alahsa), and 18.8% in Makkah. Makkah samples were only D group and had a rate of 24.4% and 12.8% in the cities of Makkah and Jeddah, respectively. The seroprevalence in Saudi Arabia across the sampled areas would be 12 times the reported COVID-19 infection rate. Among HCWs, 7.5% (4.95-10.16 CI 95%) had reactive antibodies to SARS-CoV-2 without reporting any previously confirmed infection. This was higher in HCWs with hypertension. The study also presents the demographics and prevalence of co-morbidities in HCWs and subset of non-COVID-19 population.

Interpretation: Our study estimates the overall national serological prevalence of COVID-19 in Saudi Arabia to be 11%, with an apparent disparity between regions. This indicates the prevalence of asymptomatic or mild unreported COVID-19 cases.
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http://dx.doi.org/10.1016/j.jiph.2021.04.006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8188888PMC
July 2021

Simultaneous detection and mutation surveillance of SARS-CoV-2 and multiple respiratory viruses by rapid field-deployable sequencing.

Med (N Y) 2021 Jun 31;2(6):689-700.e4. Epub 2021 Mar 31.

Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.

Background: Strategies for monitoring the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are crucial for combating the pandemic. Detection and mutation surveillance of SARS-CoV-2 and other respiratory viruses require separate and complex workflows that rely on highly specialized facilities, personnel, and reagents. To date, no method can rapidly diagnose multiple viral infections and determine variants in a high-throughput manner.

Methods: We describe a method for multiplex isothermal amplification-based sequencing and real-time analysis of multiple viral genomes, termed nanopore sequencing of isothermal rapid viral amplification for near real-time analysis (NIRVANA). It can simultaneously detect SARS-CoV-2, influenza A, human adenovirus, and human coronavirus and monitor mutations for up to 96 samples in real time.

Findings: NIRVANA showed high sensitivity and specificity for SARS-CoV-2 in 70 clinical samples with a detection limit of 20 viral RNA copies per μL of extracted nucleic acid. It also detected the influenza A co-infection in two samples. The variant analysis results of SARS-CoV-2-positive samples mirror the epidemiology of coronavirus disease 2019 (COVID-19). Additionally, NIRVANA could simultaneously detect SARS-CoV-2 and pepper mild mottle virus (PMMoV) (an omnipresent virus and water-quality indicator) in municipal wastewater samples.

Conclusions: NIRVANA provides high-confidence detection of both SARS-CoV-2 and other respiratory viruses and mutation surveillance of SARS-CoV-2 on the fly. We expect it to offer a promising solution for rapid field-deployable detection and mutational surveillance of pandemic viruses.

Funding: M.L. is supported by KAUST Office of Sponsored Research (BAS/1/1080-01). This work is supported by KAUST Competitive Research Grant (URF/1/3412-01-01; M.L. and J.C.I.B.) and Universidad Catolica San Antonio de Murcia (J.C.I.B.). A.M.H. is supported by Saudi Ministry of Education (project 436).
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http://dx.doi.org/10.1016/j.medj.2021.03.015DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8011639PMC
June 2021

A Robust, Safe, and Scalable Magnetic Nanoparticle Workflow for RNA Extraction of Pathogens from Clinical and Wastewater Samples.

Glob Chall 2021 Feb 22:2000068. Epub 2021 Feb 22.

Biological and Environmental Sciences and Engineering Division (BESE) King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Kingdom of Saudi Arabia.

Molecular diagnosis and surveillance of pathogens such as SARS-CoV-2 depend on nucleic acid isolation. Pandemics at the scale of COVID-19 can cause a global shortage of proprietary commercial reagents and BSL-2 laboratories to safely perform testing. Therefore, alternative solutions are urgently needed to address these challenges. An open-source method, magnetic-nanoparticle-aided viral RNA isolation from contagious samples (MAVRICS), built upon readily available reagents, and easily assembled in any basically equipped laboratory, is thus developed. The performance of MAVRICS is evaluated using validated pathogen detection assays and real-world and contrived samples. Unlike conventional methods, MAVRICS works directly in samples inactivated in phenol-chloroform (e.g., TRIzol), thus allowing infectious samples to be handled safely without biocontainment facilities. MAVRICS allows wastewater biomass immobilized on membranes to be directly inactivated and lysed in TRIzol followed by RNA extraction by magnetic nanoparticles, thereby greatly reducing biohazard risk and simplifying processing procedures. Using 39 COVID-19 patient samples and two wastewater samples, it is shown that MAVRICS rivals commercial kits in detection of SARS-CoV-2, influenza viruses, and respiratory syncytial virus. Therefore, MAVRICS is safe, fast, and scalable. It is field-deployable with minimal equipment requirements and could become an enabling technology for widespread testing and wastewater monitoring of diverse pathogens.
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http://dx.doi.org/10.1002/gch2.202000068DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7995109PMC
February 2021

Quick and Easy Assembly of a One-Step qRT-PCR Kit for COVID-19 Diagnostics Using In-House Enzymes.

ACS Omega 2021 Mar 15;6(11):7374-7386. Epub 2021 Mar 15.

Laboratory of DNA Replication and Recombination, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.

One-step reverse-transcription quantitative polymerase chain reaction (qRT-PCR) is the most widely applied method for COVID-19 diagnostics. Notwithstanding the facts that one-step qRT-PCR is well suited for the diagnosis of COVID-19 and that there are many commercially available one-step qRT-PCR kits in the market, their high cost and unavailability due to airport closures and shipment restriction became a major bottleneck that had driven the desire to produce the key components of such kits locally. Here, we provide a simple, economical, and powerful one-step qRT-PCR kit based on patent-free, specifically tailored versions of Moloney murine leukemia virus reverse transcriptase and DNA polymerase and termed R3T (Rapid Research Response Team) one-step qRT-PCR. We also demonstrate the robustness of our enzyme production strategies and provide the optimal reaction conditions for their efficient augmentation in a one-step approach. Our kit was routinely able to reliably detect as low as 10 copies of the synthetic RNAs of SARS-CoV-2. More importantly, our kit successfully detected COVID-19 in clinical samples of broad viral titers with similar reliability and selectivity to that of the Invitrogen SuperScript III Platinum One-step qRT-PCR and TaqPath one-step RT-qPCR kits. Overall, our kit has shown robust performance in both laboratory settings and the Saudi Ministry of Health-approved testing facility.
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http://dx.doi.org/10.1021/acsomega.0c05635DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7986002PMC
March 2021

Performance of Commercially Available Rapid Serological Assays for the Detection of SARS-CoV-2 Antibodies.

Pathogens 2020 Dec 19;9(12). Epub 2020 Dec 19.

Pathogen Genomics Laboratory, Division of Biological and Environmental Sciences and Engineering (BESE), Thuwal 23955, Saudi Arabia.

The coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), continues to spread globally. Although several rapid commercial serological assays have been developed, little is known about their performance and accuracy in detecting SARS-CoV-2-specific antibodies in COVID-19 patient samples. Here, we have evaluated the performance of seven commercially available rapid lateral flow immunoassays (LFIA) obtained from different manufacturers, and compared them to in-house developed and validated ELISA assays for the detection of SARS-CoV-2-specific IgM and IgG antibodies in RT-PCR-confirmed COVID-19 patients. While all evaluated LFIA assays showed high specificity, our data showed a significant variation in sensitivity of these assays, which ranged from 0% to 54% for samples collected early during infection (3-7 days post symptoms onset) and from 54% to 88% for samples collected at later time points during infection (8-27 days post symptoms onset). Therefore, we recommend prior evaluation and validation of these assays before being routinely used to detect IgM and IgG in COVID-19 patients. Moreover, our findings suggest the use of LFIA assays in combination with other standard methods, and not as an alternative.
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http://dx.doi.org/10.3390/pathogens9121067DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7767212PMC
December 2020

Seroprevalence of SARS-CoV-2 (COVID-19) among healthcare workers in Saudi Arabia: comparing case and control hospitals.

Diagn Microbiol Infect Dis 2021 Mar 20;99(3):115273. Epub 2020 Nov 20.

Public Health Lab, Saudi Center for Disease Prevention and Control, Riyadh, Saudi Arabia; Department of Pathology, School of Medicine, King Saud University, Riyadh, Saudi Arabia.

Healthcare workers (HCWs) stand at the frontline for fighting coronavirus disease 2019 (COVID-19) pandemic. This puts them at higher risk of acquiring the infection than other individuals in the community. Defining immunity status among health care workers is therefore of interest since it helps to mitigate the exposure risk. This study was conducted between May 20 and 30, 2020. Eighty-five hospitals across Kingdom of Saudi Arabia were divided into 2 groups: COVID-19 referral hospitals are those to which RT-PCR-confirmed COVID-19 patients were admitted or referred for management (Case-hospitals). COVID-19 nonaffected hospitals where no COVID-19 patients had been admitted or managed and no HCW outbreak (Control hospitals). Next, seroprevalence of severe acute respiratory syndrome coronavirus 2 among HCWs was evaluated; there were 12,621 HCWs from the 85 hospitals. There were 61 case-hospitals with 9379 (74.3%) observations, and 24 control-hospitals with 3242 (25.7%) observations. The overall positivity rate by the immunoassay was 299 (2.36%) with a significant difference between the case-hospital (2.9%) and the control-group (0.8%) (P value <0.001). There was a wide variation in the positivity rate between regions and/or cities in Saudi Arabia, ranging from 0% to 6.31%. Of the serology positive samples, 100 samples were further tested using the SAS2pp neutralization assay; 92 (92%) samples showed neutralization activity. The seropositivity rate in Kingdom of Saudi Arabia is low and varies across different regions with higher positivity in case-hospitals than control-hospitals. The lack of neutralizing antibodies (NAb) in 8% of the tested samples could mean that assay is a more sensitive assay or that neutralization assay has a lower detection limits; or possibly that some samples had cross-reaction to spike protein of other coronaviruses in the assay, but these were not specific to neutralize severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).
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http://dx.doi.org/10.1016/j.diagmicrobio.2020.115273DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7677039PMC
March 2021

Early Humoral Response Correlates with Disease Severity and Outcomes in COVID-19 Patients.

Viruses 2020 12 4;12(12). Epub 2020 Dec 4.

Centre for Biologics Evaluation, Biologics and Genetic Therapies Directorate, Health Products and Food Branch (HPFB), Health Canada and WHO Collaborating Center for Standardization and Evaluation of Biologicals, Ottawa, ON K1A 0K9, Canada.

The Coronavirus Disease 2019 (COVID-19), caused by SARS-CoV-2, continues to spread globally with significantly high morbidity and mortality rates. Antigen-specific responses are of unquestionable value for clinical management of COVID-19 patients. Here, we investigated the kinetics of IgM, IgG against the spike (S) and nucleoproteins (N) proteins and their neutralizing capabilities in hospitalized COVID-19 patients with different disease presentations (i.e., mild, moderate or severe), need for intensive care units (ICU) admission or outcomes (i.e., survival vs death). We show that SARS-CoV-2 specific IgG, IgM and neutralizing antibodies (nAbs) were readily detectable in almost all COVID-19 patients with various clinical presentations. Interestingly, significantly higher levels of nAbs as well as anti-S1 and -N IgG and IgM antibodies were found in patients with more severe symptoms, patients requiring admission to ICU or those with fatal outcomes. More importantly, early after symptoms onset, we found that the levels of anti-N antibodies correlated strongly with disease severity. Collectively, these findings provide new insights into the kinetics of antibody responses in COVID-19 patients with different disease severity.
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http://dx.doi.org/10.3390/v12121390DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7761967PMC
December 2020

Comparative metagenomics and characterization of antimicrobial resistance genes in pasteurized and homemade fermented Arabian laban.

Food Res Int 2020 11 26;137:109639. Epub 2020 Aug 26.

Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia; Medical Laboratory Technology Department, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.

The aim of this study was to investigate bacterial diversity and function in a fermented milk drink called laban, which is traditionally served in the Middle East, Africa, and Indian subcontinent. Pasteurized laban (LBP) and unpasteurized, homemade, raw laban (LBR) underwent 16S rRNA gene amplicon and shotgun sequencing to analyze their bacterial community, presence of antimicrobial resistance genes (ARGs), and metabolic pathways. This study highlighted relatively greater diversity in LBR bacterial populations compared to LBP, despite containing similar major taxa that consisted primarily of Firmicutes followed by Proteobacteria, Bacteroidetes, and Actinobacteria. The dominant species, Streptococcus thermophilus, was relatively more abundant in LBP (80.7%) compared to LBR (47.9%). LBR had increased diversity and higher relative abundance of several known probiotic bacteria, such as Streptococcus salivarius and Lactococcus lactis, whereas Lactobacillus acidophilus was detected at a higher abundance in LBP. Pathogens like Acinetobacter baumannii, Streptococcus pneumoniae, Streptococcus pyogenes, and Escherichia coli had lower abundance in LBP compared to LBR. Thirty-three ARGs were detected in LBR compared to nine in LBP and are responsible for resistance to 11 classes of antibiotics. A significant proportion of the metagenomes from both types of laban were assigned to housekeeping functions, such as amino acid metabolism, translation, membrane transport, and carbohydrate metabolism. LBR demonstrated increased diversity in probiotics and metabolic functions compared to LBP. However, the relatively high diversity of pathogenic and opportunistic bacteria and ARGs in LBR raises safety concerns and highlights the need for a more hygienic environment for the processing of homemade fermented dairy foods.
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http://dx.doi.org/10.1016/j.foodres.2020.109639DOI Listing
November 2020

SARS-CoV-2 S1 and N-based serological assays reveal rapid seroconversion and induction of specific antibody response in COVID-19 patients.

Sci Rep 2020 10 6;10(1):16561. Epub 2020 Oct 6.

Vaccines and Immunotherapy Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.

As the Coronavirus Disease 2019 (COVID-19), which is caused by the novel SARS-CoV-2, continues to spread rapidly around the world, there is a need for well validated serological assays that allow the detection of viral specific antibody responses in COVID-19 patients or recovered individuals. In this study, we established and used multiple indirect Enzyme Linked Immunosorbent Assay (ELISA)-based serological assays to study the antibody response in COVID-19 patients. In order to validate the assays we determined the cut off values, sensitivity and specificity of the assays using sera collected from pre-pandemic healthy controls, COVID-19 patients at different time points after disease-onset, and seropositive sera to other human coronaviruses (CoVs). The developed SARS-CoV-2 S1 subunit of the spike glycoprotein and nucleocapsid (N)-based ELISAs not only showed high specificity and sensitivity but also did not show any cross-reactivity with other CoVs. We also show that all RT-PCR confirmed COVID-19 patients tested in our study developed both virus specific IgM and IgG antibodies as early as week one after disease onset. Our data also suggest that the inclusion of both S1 and N in serological testing would capture as many potential SARS-CoV-2 positive cases as possible than using any of them alone. This is specifically important for tracing contacts and cases and conducting large-scale epidemiological studies to understand the true extent of virus spread in populations.
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http://dx.doi.org/10.1038/s41598-020-73491-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7538990PMC
October 2020

Evaluation of Neutralizing Antibodies Against Highly Pathogenic Coronaviruses: A Detailed Protocol for a Rapid Evaluation of Neutralizing Antibodies Using Vesicular Stomatitis Virus Pseudovirus-Based Assay.

Front Microbiol 2020 4;11:2020. Epub 2020 Sep 4.

Vaccines and Immunotherapy Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.

Emerging highly pathogenic human coronaviruses (CoVs) represent a serious ongoing threat to the public health worldwide. The spike (S) proteins of CoVs are surface glycoproteins that facilitate viral entry into host cells via attachment to their respective cellular receptors. The S protein is believed to be a major immunogenic component of CoVs and a target for neutralizing antibodies (nAbs) and most candidate vaccines. Development of a safe and convenient assay is thus urgently needed to determine the prevalence of CoVs nAbs in the population, to study immune response in infected individuals, and to aid in vaccines and viral entry inhibitor evaluation. While live virus-based neutralization assays are used as gold standard serological methods to detect and measure nAbs, handling of highly pathogenic live CoVs requires strict bio-containment conditions in biosafety level-3 (BSL-3) laboratories. On the other hand, use of replication-incompetent pseudoviruses bearing CoVs S proteins could represent a safe and useful method to detect nAbs in serum samples under biosafety level-2 (BSL-2) conditions. Here, we describe a detailed protocol of a safe and convenient assay to generate vesicular stomatitis virus (VSV)-based pseudoviruses to evaluate and measure nAbs against highly pathogenic CoVs. The protocol covers methods to produce VSV pseudovirus bearing the S protein of the Middle East respiratory syndrome-CoV (MERS-CoV) and the severe acute respiratory syndrome-CoV-2 (SARS-CoV-2), pseudovirus titration, and pseudovirus neutralization assay. Such assay could be adapted by different laboratories and researchers working on highly pathogenic CoVs without the need to handle live viruses in the BSL-3 environment.
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http://dx.doi.org/10.3389/fmicb.2020.02020DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7498578PMC
September 2020

Phage Display Derived Monoclonal Antibodies: From Bench to Bedside.

Front Immunol 2020 28;11:1986. Epub 2020 Aug 28.

Vaccines and Immunotherapy Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.

Monoclonal antibodies (mAbs) have become one of the most important classes of biopharmaceutical products, and they continue to dominate the universe of biopharmaceutical markets in terms of approval and sales. They are the most profitable single product class, where they represent six of the top ten selling drugs. At the beginning of the 1990s, an antibody selection technology known as antibody phage display was developed by John McCafferty and Sir. Gregory Winter that enabled the discovery of human antibodies for diverse applications, particularly antibody-based drugs. They created combinatorial antibody libraries on filamentous phage to be utilized for generating antigen specific antibodies in a matter of weeks. Since then, more than 70 phage-derived antibodies entered clinical studies and 14 of them have been approved. These antibodies are indicated for cancer, and non-cancer medical conditions, such as inflammatory, optical, infectious, or immunological diseases. This review will illustrate the utility of phage display as a powerful platform for therapeutic antibodies discovery and describe in detail all the approved mAbs derived from phage display.
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http://dx.doi.org/10.3389/fimmu.2020.01986DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7485114PMC
April 2021

iSCAN: An RT-LAMP-coupled CRISPR-Cas12 module for rapid, sensitive detection of SARS-CoV-2.

Virus Res 2020 10 18;288:198129. Epub 2020 Aug 18.

Laboratory for Genome Engineering and Synthetic Biology, Division of Biological Sciences, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia. Electronic address:

The COVID-19 pandemic caused by SARS-CoV-2 affects all aspects of human life. Detection platforms that are efficient, rapid, accurate, specific, sensitive, and user friendly are urgently needed to manage and control the spread of SARS-CoV-2. RT-qPCR based methods are the gold standard for SARS-CoV-2 detection. However, these methods require trained personnel, sophisticated infrastructure, and a long turnaround time, thereby limiting their usefulness. Reverse transcription-loop-mediated isothermal amplification (RT-LAMP), a one-step nucleic acid amplification method conducted at a single temperature, has been used for colorimetric virus detection. CRISPR-Cas12 and CRISPR-Cas13 systems, which possess collateral activity against ssDNA and RNA, respectively, have also been harnessed for virus detection. Here, we built an efficient, rapid, specific, sensitive, user-friendly SARS-CoV-2 detection module that combines the robust virus amplification of RT-LAMP with the specific detection ability of SARS-CoV-2 by CRISPR-Cas12. Furthermore, we combined the RT-LAMP-CRISPR-Cas12 module with lateral flow cells to enable highly efficient point-of-care SARS-CoV-2 detection. Our iSCAN SARS-CoV-2 detection module, which exhibits the critical features of a robust molecular diagnostic device, should facilitate the effective management and control of COVID-19.
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http://dx.doi.org/10.1016/j.virusres.2020.198129DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7434412PMC
October 2020

Cross-sectional prevalence study of MERS-CoV in local and imported dromedary camels in Saudi Arabia, 2016-2018.

PLoS One 2020 26;15(5):e0232790. Epub 2020 May 26.

King Fahd Medical Research Center, Special Infectious Agents Unit, King Abdulaziz University, Jeddah, Saudi Arabia.

The Middle East Respiratory Syndrome-Coronavirus (MERS-CoV) is an endemic virus in dromedaries. Annually, Saudi Arabia imports thousands of camels from the Horn of Africa, yet the epidemiology of MERS-CoV in these animals is largely unknown. Here, MERS-CoV prevalence was compared in imported African camels and their local counterparts. A total of 1399 paired sera and nasal swabs were collected from camels between 2016 and 2018. Imported animals from Sudan (n = 829) and Djibouti (n = 328) were sampled on incoming ships at Jeddah Islamic seaport before unloading, and local camels were sampled from Jeddah (n = 242). Samples were screened for neutralizing antibodies (nAbs) and MERS-CoV viral RNA. The overall seroprevalence was 92.7% and RNA detection rate was 17.2%. Imported camels had higher seroprevalence compared to resident herds (93.8% vs 87.6%, p <0.01) in contrast to RNA detection (13.3% vs 35.5%, p <0.0001). Seroprevalence significantly increased with age (p<0.0001) and viral RNA detection rate was ~2-folds higher in camels <2-year-old compared to older animals. RNA detection was higher in males verses females (24.3% vs 12.6%, p<0.0001) but seroprevalence was similar. Concurrent positivity for viral RNA and nAbs was found in >87% of the RNA positive animals, increased with age and was sex-dependent. Importantly, reduced viral RNA load was positively correlated with nAb titers. Our data confirm the widespread of MERS-CoV in imported and domestic camels in Saudi Arabia and highlight the need for continuous active surveillance and better prevention measures. Further studies are also warranted to understand camels correlates of protection for proper vaccine development.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0232790PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7250453PMC
June 2020

Preparedness and response to COVID-19 in Saudi Arabia: Building on MERS experience.

J Infect Public Health 2020 Jun 11;13(6):834-838. Epub 2020 May 11.

Department of Medical Microbiology and Parasitology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia; Vaccines and Immunnotherapy Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia. Electronic address:

Nearly four months have passed since the emergence of the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), which caused the rapidly spreading Coronavirus Disease 2019 (COVID-19) pandemic. To date, there have been more than 2.3 million confirmed cases and more than 160,000 deaths globally caused by COVID-19. Chinese health authorities, where the virus emerged, have taken prompt strict public health measures to control and prevent the spread of the outbreak. In Saudi Arabia, unprecedented precautionary strict measures were applied to prevent virus entry to the country or to mitigate its impact when it arrives. Here, we review the response of Saudi Arabia to COVID-19 pandemic and how did the experience learned from the Middle East respiratory syndrome coronavirus (MERS-CoV) epidemic since 2012 has helped the country to be better prepared for the current COVID-19 pandemic. We also discuss the country readiness, improvement in research and development, and the unprecedented rapid precautionary measures that have been taken by the Saudi government thus far.
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http://dx.doi.org/10.1016/j.jiph.2020.04.016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7211706PMC
June 2020

Therapeutic use of chloroquine and hydroxychloroquine in COVID-19 and other viral infections: A narrative review.

Travel Med Infect Dis 2020 May - Jun;35:101735. Epub 2020 May 6.

King Saud Medical City, Research & Innovation Center, Ministry of Health, Saudi Arabia; Al-Faisal University, Riyadh, Saudi Arabia; Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA. Electronic address:

The rapidly spreading Coronavirus Disease (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus (SARS-CoV-2), represents an unprecedented serious challenge to the global public health community. The extremely rapid international spread of the disease with significant morbidity and mortality made finding possible therapeutic interventions a global priority. While approved specific antiviral drugs against SARS-CoV-2 are still lacking, a large number of existing drugs are being explored as a possible treatment for COVID-19 infected patients. Recent publications have re-examined the use of Chloroquine (CQ) and/or Hydroxychloroquine (HCQ) as a potential therapeutic option for these patients. In an attempt to explore the evidence that supports their use in COVID-19 patients, we comprehensively reviewed the previous studies which used CQ or HCQ as an antiviral treatment. Both CQ and HCQ demonstrated promising in vitro results, however, such data have not yet been translated into meaningful in vivo studies. While few clinical trials have suggested some beneficial effects of CQ and HCQ in COVID-19 patients, most of the reported data are still preliminary. Given the current uncertainty, it is worth being mindful of the potential risks and strictly rationalise the use of these drugs in COVID-19 patients until further high quality randomized clinical trials are available to clarify their role in the treatment or prevention of COVID-19.
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http://dx.doi.org/10.1016/j.tmaid.2020.101735DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7202851PMC
July 2020

Seroprevalence of MERS-CoV in healthy adults in western Saudi Arabia, 2011-2016.

J Infect Public Health 2020 May 28;13(5):697-703. Epub 2020 Jan 28.

Vaccines and Immunotherapy Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia; Department of Medical Microbiology and Parasitology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia. Electronic address:

Background: The Middle East respiratory syndrome coronavirus (MERS-CoV) is a newly recognized zoonotic coronavirus. Current evidence confirms the role of dromedaries in primary human infections but does not explain the sporadic community cases. However, asymptomatic or subclinical cases could represent a possible source of infection in the community.

Methods: Archived human sera (7461) collected between 2011 and 2016 from healthy adult blood donors from 50 different nationalities in the western part of Saudi Arabia were obtained for MERS-CoV seroprevalence investigation. Samples were tested for MERS-CoV S1-specific antibodies (Abs) by ELISA and confirmed by testing for neutralizing Abs (nAbs) using both pseudotyped and live virus neutralization assays.

Results: Out of 7461 samples, 174 sera from individuals with 18 different nationalities were ELISA positive (2.3%, 95% CI 2.0-2.7). Presence of nAbs was confirmed in 17 samples (0.23%, 95% CI 0.1-0.4) of which one sample exhibited positivity in both neutralization assays. Confirmed seropositivity was identified in young (15-44 years) men and women from Saudi Arabia, Egypt, Yemen, Pakistan, Palestine, Sudan, and India without significant preference.

Conclusions: An increasing trend of MERS-CoV seroprevalence was observed in the general population in western Saudi Arabia, suggesting that asymptomatic or mild infections might exist and act as an unrecognized source of infection. Seropositivity of individuals from different nationalities underscores the potential MERS exportation outside of the Arabian Peninsula. Thus, enhanced and continuous surveillance is highly warranted.
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http://dx.doi.org/10.1016/j.jiph.2020.01.001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7104088PMC
May 2020

Qualitative and Quantitative Determination of MERS-CoV S1-Specific Antibodies Using ELISA.

Methods Mol Biol 2020 ;2099:127-133

Department of Medical Microbiology and Parasitology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia.

Indirect enzyme-linked immunosorbent assay (ELISA) enables detection and quantification of antigen-specific antibodies in biological samples such as human or animal sera. Most current MERS-CoV serological assays such as neutralization, immunofluorescence, or protein microarray rely on handling of live MERS-CoV in high containment laboratories, highly trained personnel as well as the need for expensive and special equipment and reagents representing a hurdle for most laboratories especially when resources are limited. In this chapter, we describe a validated and optimized indirect ELISA protocol based on recombinant S1 subunit (amino acids 1-725) of MERS-CoV for qualitative and quantitative determination of MERS-CoV-binding antibodies.
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http://dx.doi.org/10.1007/978-1-0716-0211-9_11DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7122216PMC
September 2020

Generation of MERS-CoV Pseudotyped Viral Particles for the Evaluation of Neutralizing Antibodies in Mammalian Sera.

Methods Mol Biol 2020 ;2099:117-126

Department of Medical Microbiology and Parasitology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia.

Pseudotyped viral particle production has been used extensively and broadly for many viruses to evaluate levels of neutralizing antibodies, viral entry inhibitors and vaccine immunogenicity. This assay is extremely safe and useful alternative to live virus-based assay without the need for high containment facilities. In this chapter, we describe the generation of MERS-CoV pseudotyped viral particles (MERSpp) expressing full-length spike protein using second-generation lentiviral packaging system. This platform is optimized to generate high titer of MERSpp and to test sera from different mammalian species.
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http://dx.doi.org/10.1007/978-1-0716-0211-9_10DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7123069PMC
September 2020

Evaluation of MERS-CoV Neutralizing Antibodies in Sera Using Live Virus Microneutralization Assay.

Methods Mol Biol 2020 ;2099:107-116

Department of Medical Microbiology and Parasitology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia.

The microneutralization (MN) assay is a standard and important technique in virology, immunology, and epidemiology. It is a highly specific and sensitive assay for evaluating virus-specific neutralizing antibodies (nAbs) in human and animal sera. It provides the most precise answer to whether or not an individual or animal has antibodies that can neutralize or inhibit the infectivity of a specific virus strain. However, using live virus-based MN assay might require working under high containment facilities especially when dealing with high-risk pathogens such as the Middle East respiratory syndrome-coronavirus (MERS-CoV). In this chapter, we describe the isolation, amplification, and titration of MERS-CoV, as well as detailed MN assay to measure nAb levels in sera from different mammalian species.
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http://dx.doi.org/10.1007/978-1-0716-0211-9_9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7121888PMC
September 2020

Quantification of the Middle East Respiratory Syndrome-Coronavirus RNA in Tissues by Quantitative Real-Time RT-PCR.

Methods Mol Biol 2020 ;2099:99-106

Departments of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA.

Since the emergence of the Middle East respiratory syndrome-coronavirus (MERS-CoV) in 2012, more than 2280 confirmed human infections and 800 associated deaths had been reported to the World Health Organization. MERS-CoV is a single-stranded RNA virus that belongs to the Coronaviridae family. MERS-CoV infection leads to a variety of clinical outcomes in humans ranging from asymptomatic and mild infection to severe acute lung injury and multi-organ failure and death. To study the pathogenesis of MERS-CoV infection and development of medical countermeasures (MCMs) for MERS, a number of genetically modified mouse models have been developed, including various versions of transgenic mice expressing the human DPP4 viral receptor. Tracking and quantifying viral infection, among others, in permissive hosts is a key endpoint for studying MERS pathogenesis and evaluating the efficacy of selected MCMs developed for MERS. In addition to quantifying infectious progeny virus which requires high-containment biosafety level (BSL)-3 laboratory, here we outlined an established real-time quantitative RT-PCR (RT-qPCR)-based procedure to unequivocally quantify MERS-CoV-specific RNAs within the lungs of infected human DPP4 (hDPP4, transgenic (hDPP4 Tg) mice under a standard BSL-2 laboratory.
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http://dx.doi.org/10.1007/978-1-0716-0211-9_8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7122982PMC
September 2020

Enzootic patterns of Middle East respiratory syndrome coronavirus in imported African and local Arabian dromedary camels: a prospective genomic study.

Lancet Planet Health 2019 12 16;3(12):e521-e528. Epub 2019 Dec 16.

Special Infectious Agent Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia; Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia. Electronic address:

Background: The Middle East respiratory syndrome coronavirus (MERS-CoV) is a lethal zoonotic pathogen endemic to the Arabian Peninsula. Dromedary camels are a likely source of infection and the virus probably originated in Africa. We studied the genetic diversity, geographical structure, infection prevalence, and age-associated prevalence among camels at the largest entry port of camels from Africa into the Arabian Peninsula.

Methods: In this prospective genomic study, we took nasal samples from camels imported from Sudan and Djibouti into the Port of Jeddah in Jeddah, Saudi Arabia, over an almost 2-year period and local Arabian camels over 2 months in the year after surveillance of the port. We determined the prevalence of MERS-CoV infection, age-associated patterns of infection, and undertook phylogeographical and migration analyses to determine intercountry virus transmission after local lineage establishment. We compared all virological characteristics between the local and imported cohorts. We compared major gene deletions between African and Arabian strains of the virus. Reproductive numbers were inferred with Bayesian birth death skyline analyses.

Findings: Between Aug 10, 2016, and May 3, 2018, we collected samples from 1196 imported camels, of which 868 originated from Sudan and 328 from Djibouti, and between May 1, and June 25, 2018, we collected samples from 472 local camels, of which 189 were from Riyadh and 283 were from Jeddah, Saudi Arabia. Virus prevalence was higher in local camels than in imported camels (224 [47·5%] of 472 vs 157 [13·1%] of 1196; p<0·0001). Infection prevalence peaked among camels older than 1 year and aged up to 2 years in both groups, with 255 (66·9%) of 381 positive cases in this age group. Although the overall geographical distribution of the virus corresponded with the phylogenetic tree topology, some virus exchange was observed between countries corresponding with trade routes in the region. East and west African strains of the virus appear to be geographically separated, with an origin of west African strains in east Africa. African strains of the virus were not re-sampled in Saudi Arabia despite sampling approximately 1 year after importation from Africa. All local Arabian samples contained strains of the virus that belong to a novel recombinant clade (NRC) first detected in 2014 in Saudi Arabia. Reproduction number estimates informed by the sequences suggest sustained endemicity of NRC, with a mean R of 1·16.

Interpretation: Despite frequent imports of MERS-CoV with camels from Africa, African lineages of MERS-CoV do not establish themselves in Saudi Arabia. Arabian strains of the virus should be tested for changes in virulence and transmissibility.

Funding: German Ministry of Research and Education, EU Horizon 2020, and Emerging Diseases Clinical Trials Partnership.
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http://dx.doi.org/10.1016/S2542-5196(19)30243-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6926486PMC
December 2019

Prevalence of human papillomavirus in Jeddah, Saudi Arabia.

Ann Saudi Med 2019 Nov-Dec;39(6):403-409. Epub 2019 Dec 5.

From the Department of Medical Microbiology and Parasitology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia.

Background: Human papillomaviruses (HPVs) are small, non-enveloped, double-stranded DNA viruses that consist of more than 200 genotypes. Low-risk genotypes are associated with warts or benign lesions, whereas high-risk genotypes are usually associated with malignancies and cancers including cervical cancer. However, the real prevalence and incidence of HPV in Saudi Arabia may be understated due to a lack of comprehensive data reporting.

Objectives: Determine the positivity rate of HPV in men and women in Jeddah, Saudi Arabia.

Design: Cross-sectional.

Setting: Tertiary care center in Jeddah.

Subjects And Methods: Self-collected vaginal swab samples were obtained from females attending the gynecological clinic in the period between October 2017 and April 2018 at a tertiary care center, Jeddah, Saudi Arabia. PCR-positive HPV samples were sequenced to determine genotype. Additionally, serum samples were collected from healthy male and female blood donors and screened for HPV IgG antibodies by ELISA.

Main Outcome Measures: Molecular and serological positivity for HPV.

Sample Size: 119 self-collected vaginal swabs from females at a gynecology clinic and 966 serum samples from healthy blood donors.

Results: Of the 119 tested vaginal swabs, 7 samples (5.9%) were positive for HPV DNA. Several genotypes were identified. Most of the positive samples were from Saudi females in the age range of 31-50 years seeking care for infertility. Of the 966 serum samples, only 16 samples (1.7%) were positive for HPV IgG antibodies.

Conclusion: While the prevalence of HPV in men and women in our sample from the western region of Saudi Arabia was low, our data clearly show that it is not uncommon among high-risk groups and people are still exposed to the risk of HPV infection. Most importantly, these data provide valuable information that could aid in enhancing national awareness about HPV and in introducing an HPV vaccination program.

Limitations: Single hospital and a convenience sample CONFLICT OF INTEREST: None.
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http://dx.doi.org/10.5144/0256-4947.2019.403DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6894452PMC
April 2020

Humoral Immunogenicity and Efficacy of a Single Dose of ChAdOx1 MERS Vaccine Candidate in Dromedary Camels.

Sci Rep 2019 11 8;9(1):16292. Epub 2019 Nov 8.

Department of Infectious Disease Research, King Abdullah International Medical Research Center, Riyadh, Saudi Arabia.

MERS-CoV seronegative and seropositive camels received a single intramuscular dose of ChAdOx1 MERS, a replication-deficient adenoviral vectored vaccine expressing MERS-CoV spike protein, with further groups receiving control vaccinations. Infectious camels with active naturally acquired MERS-CoV infection, were co-housed with the vaccinated camels at a ratio of 1:2 (infected:vaccinated); nasal discharge and virus titres were monitored for 14 days. Overall, the vaccination reduced virus shedding and nasal discharge (p = 0.0059 and p = 0.0274, respectively). Antibody responses in seropositive camels were enhancedby the vaccine; these camels had a higher average age than seronegative. Older seronegative camels responded more strongly to vaccination than younger animals; and neutralising antibodies were detected in nasal swabs. Further work is required to optimise vaccine regimens for younger seronegative camels.
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http://dx.doi.org/10.1038/s41598-019-52730-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6841732PMC
November 2019

Molecular Evidence of Influenza A Virus Circulation in African Dromedary Camels Imported to Saudi Arabia, 2017-2018.

Open Forum Infect Dis 2019 Oct 30;6(10):ofz370. Epub 2019 Sep 30.

Vaccines and Immunotherapy Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.

Little is known about influenza A viruses in dromedaries. Here, we detected influenza A viral RNA in 11 specimens (1.7 %) out of 665 nasal swabs collected from dromedaries between 2017 and 2018 in Saudi Arabia. Positive samples were detected only in imported camels from Sudan and Djibouti but not local ones. Partial genome sequencing indicates a close relationship to 2009-2019 human/swine influenza A H1N1 isolates from different countries, suggesting possible interspecies transmission. Taken together, dromedaries could represent a potentially unrecognized permissive host for these viruses, highlighting the need for enhanced surveillance in animals to aid implementation of one-health strategies.
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http://dx.doi.org/10.1093/ofid/ofz370DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6767964PMC
October 2019

Taxonomic diversity of antimicrobial-resistant bacteria and genes in the Red Sea coast.

Sci Total Environ 2019 Aug 22;677:474-483. Epub 2019 Apr 22.

Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia; Medical Laboratory Technology Department, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.

Despite development of a record number of recreational sites and industrial zones on the Red Sea coast in the last decade, antibiotic-resistant bacteria in this environment remain largely unexplored. In this study, 16S rDNA sequencing was used to identify bacteria isolated from 12 sediment samples collected from the Red Sea coastal, offshore, and mangroves sites. Quantitative PCR was used to estimate the quantity of antimicrobial resistance genes (ARGs) in genomic DNA in the samples. A total of 470 bacteria were isolated and classified into 137 distinct species, including 10 candidate novel species. Site-specific bacterial communities inhabiting the Red Sea were apparent. Relatively, more resistant isolates were recovered from the coast, and samples from offshore locations contained the most multidrug-resistant bacteria. Eighteen ARGs were detected in this study encoding resistance to aminoglycoside, beta-lactam, sulfonamide, macrolide, quinolone, and tetracycline antibiotics. The qnrS, aacC2, ermC, and bla genes were commonly found in coastal and offshore sites. Relatively higher abundance of ARGs, including aacC2 and aacC3, were found in the apparently anthropogenically contaminated (beach) samples from coast compared to other collected samples. In conclusion, a relative increase in antimicrobial-resistant isolates was found in sediment samples from the Red Sea, compared to other studies. Anthropogenic activities likely contribute to this increase in bacterial diversity and ARGs.
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http://dx.doi.org/10.1016/j.scitotenv.2019.04.283DOI Listing
August 2019

Unveiling Integrated Functional Pathways Leading to Enhanced Respiratory Disease Associated With Inactivated Respiratory Syncytial Viral Vaccine.

Front Immunol 2019 29;10:597. Epub 2019 Mar 29.

Centre for Biologics Evaluation, Biologics and Genetic Therapies Directorate, Health Products and Food Branch (HPFB), Health Canada and WHO Collaborating Center for Standardization and Evaluation of Biologicals, Ottawa, ON, Canada.

Respiratory syncytial virus (RSV) infection is a severe threat to young children and the elderly. Despite decades of research, no vaccine has been approved. Notably, instead of affording protection, a formalin-inactivated RSV vaccine induced severe respiratory disease including deaths in vaccinated children in a 1960s clinical trial; however, recent studies indicate that other forms of experimental vaccines can also induce pulmonary pathology in pre-clinical studies. These findings suggest that multiple factors/pathways could be involved in the development of enhanced respiratory diseases. Clearly, a better understanding of the mechanisms underlying such adverse reactions is critically important for the development of safe and efficacious vaccines against RSV infection, given the exponential growth of RSV vaccine clinical trials in recent years. By employing an integrated systems biology approach in a pre-clinical cotton rat model, we unraveled a complex network of pulmonary canonical pathways leading to disease development in vaccinated animals upon subsequent RSV infections. Cytokines including IL-1, IL-6 GRO/IL-8, and IL-17 in conjunction with mobilized pulmonary inflammatory cells could play important roles in disease development, which involved a wide range of host responses including exacerbated pulmonary inflammation, oxidative stress, hyperreactivity, and homeostatic imbalance between coagulation and fibrinolysis. Moreover, the observed elevated levels of MyD88 implicate the involvement of this critical signal transduction module as the central node of the inflammatory pathways leading to exacerbated pulmonary pathology. Finally, the immunopathological consequences of inactivated vaccine immunization and subsequent RSV exposure were further substantiated by histological analyses of these key proteins along with inflammatory cytokines, while hypercoagulation was supported by increased pulmonary fibrinogen/fibrin accompanied by reduced levels of plasma D-dimers. Enhanced respiratory disease associated with inactivated RSV vaccine involves a complex network of host responses, resulting in significant pulmonary lesions and clinical manifestations such as tachypnea and airway obstruction. The mechanistic insight into the convergence of different signal pathways and identification of biomarkers could help facilitate the development of safe and effective RSV vaccine and formulation of new targeted interventions.
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http://dx.doi.org/10.3389/fimmu.2019.00597DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6449435PMC
August 2020

A Highly Immunogenic, Protective, and Safe Adenovirus-Based Vaccine Expressing Middle East Respiratory Syndrome Coronavirus S1-CD40L Fusion Protein in a Transgenic Human Dipeptidyl Peptidase 4 Mouse Model.

J Infect Dis 2019 10;220(10):1558-1567

Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston.

Background: Infection control measures have played a major role in limiting human/camel-to-human transmission of Middle East respiratory syndrome coronavirus (MERS-CoV); however, development of effective and safe human or camel vaccines is warranted.

Methods: We extended and optimized our previous recombinant adenovirus 5 (rAd5)-based vaccine platform characterized by in vivo amplified and CD40-mediated specific responses to generate MERS-CoV S1 subunit-based vaccine. We generated rAd5 constructs expressing CD40-targeted S1 fusion protein (rAd5-S1/F/CD40L), untargeted S1 (rAd5-S1), and Green Fluorescent Protein (rAd5-GFP), and evaluated their efficacy and safety in human dipeptidyl peptidase 4 transgenic (hDPP4 Tg+) mice.

Results: Immunization of hDPP4 Tg+ mice with a single dose of rAd5-S1/F/CD40L elicited as robust and significant specific immunoglobulin G and neutralizing antibodies as those induced with 2 doses of rAd5-S1. After MERS-CoV challenge, both vaccines conferred complete protection against morbidity and mortality, as evidenced by significantly undetectable/reduced pulmonary viral loads compared to the control group. However, rAd5-S1- but not rAd5-S1/F/CD40L-immunized mice exhibited marked pulmonary perivascular hemorrhage post-MERS-CoV challenge despite the observed protection.

Conclusions: Incorporation of CD40L into rAd5-based MERS-CoV S1 vaccine targeting molecule and molecular adjuvants not only enhances immunogenicity and efficacy but also prevents inadvertent pulmonary pathology after viral challenge, thereby offering a promising strategy to enhance safety and potency of vaccines.
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http://dx.doi.org/10.1093/infdis/jiz137DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7107499PMC
October 2019

MERS-CoV, influenza and other respiratory viruses among symptomatic pilgrims during 2014 Hajj season.

J Med Virol 2019 06 20;91(6):911-917. Epub 2019 Feb 20.

Special Infectious Agent Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.

More than two million Muslims visit Makkah, Saudi Arabia, annually to perform the religious rituals of Hajj where the risk of spreading respiratory infections is very common. The aim here was to screen symptomatic pilgrims for Middle East respiratory syndrome coronavirus (MERS-CoV) and other viral etiologies. Thus, 132 nasopharyngeal samples were collected from pilgrims presenting with acute respiratory symptoms at the healthcare facilities in the holy sites during the 5 days of the 2014 Hajj season. Samples were tested using real-time reverse transcription polymerase chain reactions and microarray. Demographic data including age, sex, and country of origin were obtained for all participants. While we did not detect MERS-CoV in any of the samples, several other viruses were detected in 50.8% of the cases. Among the detected viruses, 64.2% of the cases were due to a single-virus infection and 35.8% were due to the coinfections with up to four viruses. The most common respiratory virus was influenza A, followed by non-MERS human coronaviruses, rhinoviruses, and influenza B. Together, we found that it was not MERS-CoV but other respiratory viruses that caused acute respiratory symptoms among pilgrims. The observed high prevalence of influenza viruses underscores the need for more effective surveillance during the Hajj and adoption of stringent vaccination requirements from all pilgrims.
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http://dx.doi.org/10.1002/jmv.25424DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7166944PMC
June 2019

Development and validation of different indirect ELISAs for MERS-CoV serological testing.

J Immunol Methods 2019 03 16;466:41-46. Epub 2019 Jan 16.

Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia; Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.

Since 2012, MERS-CoV has caused up to 2220 cases and 790 deaths in 27 countries with Saudi Arabia being the most affected country with ~83.1% of the cases and ~38.8% local death rate. Current serological assays such as microneutralization (MN), plaque reduction neutralization, immunofluorescence, protein microarray or pseudoparticle neutralization assays rely on handling of live MERS-CoV in high containment laboratories or need for expensive and special equipment and reagents and highly trained personnel which represent a technical hurdle for most laboratories in resource-limited MERS-CoV endemic countries. Here, we developed, compared and evaluated three different indirect ELISAs based on MERS-CoV nucleocapsid protein (N), spike (S) ectodomain (amino acids 1-1297) and S1 subunit (amino acids 1-725) and compared them with MN assay. The developed ELISAs were evaluated using large number of confirmed seropositive (79 samples) and seronegative (274 samples) MERS-CoV human serum samples. Both rS1- and rS-ELISAs maintained high sensitivity and specificity (≥90%) across a wider range of OD values compared to rN-ELISA. Moreover, rS1- and rS-based ELISAs showed better agreement and correlation with MN assay in contrast to rN-ELISA. Collectively, our data demonstrate that rS1-ELISA and rS-ELISA are more reliable than rN-ELISA and represent a suitable choice for seroepidemiological testing and surveillance in MERS-CoV endemic regions.
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http://dx.doi.org/10.1016/j.jim.2019.01.005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7094657PMC
March 2019

No molecular evidence of MERS-CoV circulation in Jeddah, Saudi Arabia between 2010-2012: a single-center retrospective study.

J Infect Dev Ctries 2018 May 31;12(5):390-393. Epub 2018 May 31.

King Abdulaziz University, Jeddah, Saudi Arabia.

Introduction: Middle East respiratory syndrome coronavirus (MERS-CoV) is an emerging zoonotic viral pathogen and a serious public health concern. The virus was first reported in Saudi Arabia in 2012 and continues to be endemic in the region. Most of the initial MERS-CoV cases in 2012 and early 2013 were sporadic, and it remains unclear whether MERS-CoV was circulating before 2012 or not. Therefore, we tried here to find any molecular evidence of MERS-CoV circulation in humans before or during 2012 in the city of Jeddah, Saudi Arabia.

Methodology: We examined 349 archived respiratory samples collected between January 2010 and December 2012 from patients with acute respiratory illnesses from the city of Jeddah in Western Saudi Arabia. All samples were screened for MERS-CoV by real-time RT-PCR targeting the upstream E-gene (UpE) and the open reading frame 1 a (ORF1a).

Results: All tested samples which were originally found negative for influenza A H1N1 virus were also found to be negative for MERS-CoV.

Conclusions: These results suggest that circulation of MERS-CoV was uncommon among patients with acute respiratory symptoms in Western Saudi Arabia between 2010 and 2012.
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http://dx.doi.org/10.3855/jidc.9523DOI Listing
May 2018
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