Adhesion of Candida Albicans to digital versus conventional acrylic resins: a systematic review and meta-analysis.

BACKGROUND: The present systematic review and meta-analysis investigated the available evidence about the adherence of Candida Albicans to the digitally-fabricated acrylic resins (both milled and 3D-printed) compared to the conventional heat-polymerized acrylic resins. METHODS: This study followed the guidelines of the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA). A comprehensive search of online databases/search tools (Web of Science, Scopus, PubMed, Ovid, and Google Scholar) was conducted for all relevant studies published up until May 29, 2023. Only in-vitro studies comparing the adherence of Candida albicans to the digital and conventional acrylic resins were included. The quantitative analyses were performed using RevMan v5.3 software. RESULTS: Fourteen studies were included, 11 of which were meta-analyzed based on Colony Forming Unit (CFU) and Optical Density (OD) outcome measures. The pooled data revealed significantly lower candida colonization on the milled digitally-fabricated compared to the heat-polymerized conventionally-fabricated acrylic resin materials (MD = - 0.36; 95%CI = - 0.69, - 0.03; P = 0.03 and MD = - 0.04; 95%CI = - 0.06, - 0.01; P = 0.0008; as measured by CFU and OD respectively). However, no differences were found in the adhesion of Candida albicans between the 3D-printed digitally-fabricated compared to the heat-polymerized conventionally-fabricated acrylic resin materials (CFU: P = 0.11, and OD: P = 0.20). CONCLUSION: The available evidence suggests that candida is less likely to adhere to the milled digitally-fabricated acrylic resins compared to the conventional ones.

Microsatellite-based analysis reveals Aedes aegypti populations in the Kingdom of Saudi Arabia result from colonization by both the ancestral African and the global domestic forms.

The Aedes aegypti (Linnaeus, 1762) mosquito is the main vector of dengue, chikungunya and Zika and is well established today all over the world. The species comprises two forms: the ancestral form found throughout Africa and a global domestic form that spread to the rest of the tropics and subtropics. In Saudi Arabia, A. aegypti has been known in the southwest since 1956, and previous genetic studies clustered A. aegypti from Saudi Arabia with the global domestic form. The purpose of this study was to assess the genetic structure of A. aegypti in Saudi Arabia and determine their geographic origin. Genetic data for 17 microsatellites were collected for A. aegypti ranging from the southwestern highlands of Saudi Arabia on the border of Yemen to the north-west in Madinah region as well as from Thailand and Uganda populations (as representatives of the ancestral African and global domestic forms, respectively). The low but significant level of genetic structuring in Saudi Arabia was consistent with long-distance dispersal capability possibly through road connectivity and human activities, that is, passive dispersal. There are two main genetic groupings in Saudi Arabia, one of which clusters with the Ugandan population and the other with the Thailand population with many Saudi Arabian individuals having mixed ancestry. The hypothesis of genetic admixture of the ancestral African and global domestic forms in Saudi Arabia was supported by approximate Bayesian computational analyses. The extent of admixture varied across Saudi Arabia. African ancestry was highest in the highland area of the Jazan region followed by the lowland Jazan and Sahil regions. Conversely, the western (Makkah, Jeddah and Madinah) and Najran populations corresponded to the global domesticated form. Given potential differences between the forms in transmission capability, ecology and behaviour, the findings here should be taken into account in vector control efforts in Saudi Arabia.

A disfiguring neglected tropical disease sweeps war-torn Yemen: a community-based study of prevalence and risk factors of cutaneous leishmaniasis among rural communities in the western highlands.

BACKGROUND: Cutaneous leishmaniasis (CL) is a major health problem in Yemen and is endemic in many rural areas across the country. METHODS: A community-based cross-sectional survey followed by unmatched case-control comparisons was conducted among 612 participants in Utmah district, western Yemen. A total of 223 participants were included in the case-control analysis to identify the significant risk factors. Skin scrapping samples were examined by microscopy and internal transcribed spacer 1 nested polymerase chain reaction. RESULTS: Overall, 33% (202/612) of the participants had active skin lesions and/or scars that met the clinical criteria for CL. A total of 90 (14.7%) participants had suspected active CL lesions; however, a prevalence of 8.7% (53/612) was obtained based on molecular and parasitological examination, with Leishmania tropica being the only causative agent identified. Multivariable logistic regression analyses showed that being ≤10 y old, being female, living in houses with cracked walls, living in the presence of other family members with typical ulcerating skin diseases and sleeping outside were factors significantly associated with an increased likelihood of having CL. Moreover, keeping livestock on the ground floor of the house was significantly associated with a decreased likelihood of having CL. CONCLUSION: The study reveals an alarmingly high prevalence of CL among the studied population. Therefore there is an urgent need for effective control measures and improved treatment efforts against this devastating disease.

Elevated Levels of Procoagulant Microvesicles and Tissue-Factor Bearing Microvesicles in Malaria Patients.

Background: Procoagulant microvesicles (MVs) are submicron membrane fragments released from activated cells and cells undergoing apoptosis. The procoagulant activity of MVs is enhanced in the presence of tissue factor (TF). MVs and TF are active mediators that induce pro-inflammatory response and prothrombotic tendency and have been linked to the severity of several disorders, including malaria infection. The current study aimed to measure the levels of circulating procoagulant MVs and TF-bearing MVs in malaria patients and correlate these levels with other hematological parameters and parasitemia. Materials and Methods: Levels of MVs and TF-bearing MVs in the plasma of children and adult patients infected with Plasmodium falciparum were measured alongside matched healthy controls. Results: Patients with Plasmodium falciparum infection had ~3.8 times MVs (p < 0.0001) and ~13.0 times TF-bearing MVs compared to the matched healthy controls. MVs showed inverse significant correlation with platelet count (p = 0.0055), hemoglobin (p = 0.0004) and parasitemia. Conclusion: Elevated levels of MVs and TF-bearing MVs could be useful biomarkers to evaluate the procoagulant activity, inflammatory response and parasitemia levels in malaria infection, aiding in better management of the disease.

The emergence of an imported variant of dengue virus serotype 2 in the Jazan region, southwestern Saudi Arabia.

BACKGROUND: Dengue virus (DENV) infection is a global economic and public health concern, particularly in tropical and subtropical countries where it is endemic. Saudi Arabia has seen an increase in DENV infections, especially in the western and southwestern regions. This study aims to investigate the genetic variants of DENV-2 that were circulating during a serious outbreak in Jazan region in 2019. METHODS: A total of 482 serum samples collected during 2019 from Jazan region were tested with reverse transcription-polymerase chain reaction (RT-PCR) to detect and classify DENV; positive samples underwent sequencing and bioinformatics analyses. RESULTS: Out of 294 positive samples, type-specific RT-PCR identified 58.8% as DENV-2 but could not identify 41.2%. Based on sequencing and bioinformatics analyses, the samples tested PCR positive in the first round but PCR negative in the second round were found to be imported genetic variant of DENV-2. The identified DENV-2 imported variant showed similarities to DENV-2 sequences reported in Malaysia, Singapore, Korea and China. The results revealed the imported genetic variant of DENV-2 was circulating in Jazan region that was highly prevalent and it was likely a major factor in this outbreak. CONCLUSIONS: The emergence of imported DENV variants is a serious challenge for the dengue fever surveillance and control programmes in endemic areas. Therefore, further investigations and continuous surveillance of existing and new viral strains in the region are warranted.

Molecular analysis of knockdown resistance (kdr) mutations in the voltage-gated sodium channel gene of Aedes aegypti populations from Saudi Arabia.

BACKGROUND: The Aedes aegypti mosquito is the primary vector for dengue, chikungunya, yellow fever and Zika viruses worldwide. The first record of Ae. aegypti in southwestern Saudi Arabia was in 1956. However, the first outbreak and cases of dengue fever were reported in 1994, and cases have increased in recent years. Vector control for Ae. aegypti mainly uses pyrethroid insecticides in outdoor and indoor space spraying. The constant use of pyrethroids has exerted intense selection pressure for developing target-site mutations in the voltage-gated sodium channel (vgsc) gene in Ae. Aegypti against pyrethroids-mutations that have led to knockdown resistance (kdr). METHODS: Aedes aegypti field populations from five regions (Jazan, Sahil, Makkah, Jeddah and Madinah) of southwestern Saudi Arabia were genotyped for known kdr mutations in domains IIS6 and IIIS6 of the vgsc gene using polymerase chain reaction (PCR) amplification and sequencing. We estimated the frequency of kdr mutations and genotypes from Saudi Arabia as well as from other countries, Thailand, Myanmar (Southeast Asia) and Uganda (East Africa). We constructed haplotype networks to infer the evolutionary relationships of these gene regions. RESULTS: The three known kdr mutations, S989P, V1016G (IIS6) and F1534C (IIIS6), were detected in all five regions of Saudi Arabia. Interestingly, the triple homozygous wild genotype was reported for the first time in two individuals from the highlands of the Jazan region and one from the Al-Quoz, Sahil region. Overall, nine genotypes comprising four haplotypes were observed in southwestern Saudi Arabia. The median-joining haplotype networks of eight populations from Saudi Arabia, Southeast Asia and East Africa for both the IIS6 and IIIS6 domains revealed that haplotype diversity was highest in Uganda and in the Jazan and Sahil regions of Saudi Arabia, whereas haplotype diversity was low in the Jeddah, Makkah and Madinah regions. Median-joining haplotype networks of both domains indicated selection acting on the kdr-mutation containing haplotypes in Saudi Arabia. CONCLUSIONS: The presence of wild type haplotypes without any of the three kdr mutations, i.e. that are fully susceptible, in Saudi Arabia indicates that further consideration should be given to insecticide resistance management strategies that could restore pyrethroid sensitivity to the populations of Ae. aegypti in Saudi Arabia as part of an integrative vector control strategy.

Patterns of Hepatitis B, Hepatitis C and HIV Among Blood Donors in Samtah-Jazan Region.

BACKGROUND AND OBJECTIVE: Transfusion-transmitted infectious agents are amongst the major health burden worldwide. The purpose of this study was to evaluate the prevalence of hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV) among blood donors in Samtah General Hospital, Jazan region, Saudi Arabia. MATERIAL AND METHODS: In this retrospective study, blood donation records of all blood donors recruited between January 2019 and August 2020 were included for data acquisition. A total of 4977 blood donors' records were reviewed and data were analysed. RESULTS: Hepatitis B profile showed 0.60% blood donors positive for hepatis B surface antigen (HBsAg). Nucleic acid testing (NAT) showed the presence of HBV-DNA in 0.4% of the blood donors. Anti-HBs and anti-HBc antibodies were reactive in 3.34% and 7.31% blood donors' units, respectively. Anti-HCV antibodies were reactive among 54 (1.09%) blood donors. Upon reviewing the NAT analysis results, 0.16% (08) blood donors showed the presence of HCV-RNA in their blood units. Anti-HIV antibodies were reactive in 8 (0.16%) blood donors. CONCLUSION: It is concluded that the frequency of HBsAg is comparatively lower while anti-HCV positivity is higher in Samtah, Jazan as a region compared to other regions of the country. Further studies are warranted to evaluate the cause of HCV infection in this area. Frequency of HIV is uncommon in this area.

Comparison of Rapid Diagnostic Test, Microscopy, and Polymerase Chain Reaction for the Detection of Plasmodium falciparum Malaria in a Low-Transmission Area, Jazan Region, Southwestern Saudi Arabia.

This cross-sectional study aimed to assess the performances of a rapid diagnostic test (RDT)-the AllTest Malaria p.f./p.v., microscopy, and nested polymerase chain reaction (PCR) for diagnosing Plasmodium falciparum malaria in 400 febrile patients from a low-transmission region (Jazan) in southwestern Saudi Arabia. Diagnostic performance of all three methods was compared using microscopy and nested PCR as reference methods. Overall, 42 (10.5%), 48 (12.0%), and 57 (14.3%) samples were found positive by microscopy, RDT, and PCR, respectively. With PCR as reference method, the RDT showed higher sensitivity (79% vs. 71.9%), similar specificity (99.1% vs. 99.7%), and better NLR (0.20 vs. 0.27) and area under the curve (89.0% vs. 85.8%) than microscopy. The sensitivity of RDT and microscopy decreased as age increased, and false negatives were associated with low parasite density. In addition, the sensitivity of RDT and microscopy was higher in non-Saudi than in Saudi participants. Against microscopy, both RDT and PCR showed high sensitivity (83.3% vs. 97.6%), specificity (96.4% vs. 95.5%), and NPVs (98.0% vs. 99.7%), but reduced PPVs (72.9% vs. 71.9%), respectively. The results showed that the performance of the AllTest Malaria p.f./p.v RDT was better than that of microscopy in diagnosing P. falciparum malaria among febrile patients in the Jazan region when nested PCR was used as the reference. However, further studies are required to assess malaria diagnostic methods among asymptomatic individuals in the region.

Procoagulant Microvesicles in COVID-19 Patients: Possible Modulators of Inflammation and Prothrombotic Tendency.

Background: The hypercoagulability and thrombotic tendency in coronavirus disease 2019 (COVID-19) is multifactorial, driven mainly by inflammation, and endothelial dysfunction. Elevated levels of procoagulant microvesicles (MVs) and tissue factor-bearing microvesicles (TF-bearing MVs) have been observed in many diseases with thrombotic tendency. The current study aimed to measure the levels of procoagulant MVs and TF-bearing MVs in patients with COVID-19 and healthy controls and to correlate their levels with platelet counts, D-Dimer levels, and other proposed calculated inflammatory markers. Materials and Methods: Forty ICU-admitted patients with COVID-19 and 37 healthy controls were recruited in the study. Levels of procoagulant MVs and TF-bearing MVs in the plasma of the study population were measured using enzyme linked immunosorbent assay. Results: COVID-19 patients had significantly elevated levels of procoagulant MVs and TF-bearing MVs as compared with healthy controls (P<0.001). Procoagulant MVs significantly correlated with TF-bearing MVs, D-dimer levels, and platelet count, but not with calculated inflammatory markers (neutrophil/lymphocyte ratio, platelet/lymphocyte ratio, and platelet/neutrophil ratio). Conclusion: Elevated levels of procoagulant MVs and TF-bearing MVs in patients with COVID-19 are suggested to be (i) early potential markers to predict the severity of COVID-19 (ii) a novel circulatory biomarker to evaluate the procoagulant activity and severity of COVID-19.

Human Alkhumra hemorrhagic Fever: Emergence, history and epidemiological and clinical profiles.

Alkhumra hemorrhagic fever (AHF) is a severe, often fatal hemorrhagic disease in humans. It is caused by Alkhumra hemorrhagic fever virus (AHFV), a newly described flavivirus first isolated in 1995 in Alkhumra district, south of Jeddah City, Saudi Arabia. It is transmitted from infected livestock animals to humans by direct contact with infected animals or by tick bites. In the recent past, the incidence of AHF has increased, with a total of 604 confirmed cases have been reported in Saudi Arabia between 1995 and 2020. Yet, no specific treatment or control strategies have been developed and implemented against this infection. Hence, the likelihood of increased prevalence or the occurrence of outbreaks is high, particularly in the absence of appropriate prevention and control strategies. This narrative review presents an overview of the current knowledge and future concerns about AHF globally.

Prospective Evaluation of Side-Effects Following the First Dose of Oxford/AstraZeneca COVID-19 Vaccine among Healthcare Workers in Saudi Arabia.

BACKGROUND: Several different types of vaccines have been developed for the prevention of coronavirus disease (COVID-19). Despite several local and systemic side-effects to COVID-19 vaccination reported, the vaccines are still considered the best intervention to tackle the spread of the virus and reduce the severity of COVID-19 infection. However, the reported side-effects continue to have a crucial role in public confidence in the vaccine and its acceptance. This study aimed to investigate the short-term side-effects reported by the healthcare workers (HCWs) in Saudi Arabia after receiving the first dose of the Oxford/AstraZeneca (ChAdOx1 nCoV-19) COVID-19 vaccine. METHODS: A prospective cohort study was conducted among HCWs in the Jazan region of southwestern Saudi Arabia. Healthcare workers who had received the first dose of the COVID-19 vaccine and agreed to participate in the study were followed up for 3 weeks post vaccination through a weekly online survey. Information was collected on local and/or systemic side-effects reported following vaccine administration. Participants' general and demographic information was also collected. RESULTS: A total of 57.2% (250/437) of the HCWs who participated in this study reported at least one side-effect. Injection site pain and redness (80.0%), fever (73.2%), whole-body pain/fatigue (56.4%), and headache (48.8%) were the most commonly reported side-effects. Moreover, 12.4% of the participants who reported side-effects needed to see a physician, and only one female participant was admitted to the hospital. Multivariate regression analyses revealed that nationality (Saudi, adjusted odds ratio (aOR) = 3.65; 95% CI = 2.40, 5.55) and residency (Jazan governorate, aOR = 0.38; 95% CI = 0.15, 0.95) were the significant factors associated with reporting COVID-19 post-vaccination side-effects, while the number of reported side-effects was found to be significantly influenced by occupation (medical, aOR = 0.42; 95% CI = 0.26, 0.66; p < 0.001) and gender (female, aOR = 0.61; 95% CI = 0.38, 0.97; p = 0.038). CONCLUSIONS: Findings of the present study support the safety of the Oxford/AstraZeneca COVID-19 vaccine among HCWs in Saudi Arabia. All the reported side-effects were mild-to-moderate side-effects. The findings may help convince vaccine-hesitant individuals and skeptics to accept the COVID-19 vaccine.

Polymorphism analysis of pfmdr1 gene in Plasmodium falciparum isolates 11 years post-adoption of artemisinin-based combination therapy in Saudi Arabia.

A total of 227 Plasmodium falciparum isolates from Jazan region, southwestern Saudi Arabia were amplified for the P. falciparum multi-drug resistance 1 (pfmdr1) gene to detect point mutations 11 years after the introduction of artemisinin-based combination therapy (ACT) in Saudi Arabia. The pfmdr1 86Y mutation was found in 11.5% (26/227) of the isolates while the N86 wild allele was detected in 88.5%. Moreover, 184F point mutations dominated (86.3%) the instances of pfmdr1 polymorphism while no mutation was observed at codons 1034, 1042 and 1246. Three pfmdr1 haplotypes were identified, NFSND (74.9%), NYSND (13.7%) and YFSND (11.4%). Associations of the prevalence of 86Y mutation and YFSND haplotype with participants' nationality, residency and parasitaemia level were found to be significant (P < 0.05). The findings revealed significant decline in the prevalence of the pfmdr1 86Y mutation in P. falciparum isolates from Jazan region over a decade after the implementation of ACT treatment. Moreover, the high prevalence of the NFSND haplotype might be indicative of the potential emergence of CQ-sensitive but artemether-lumefantrine-resistant P. falciparum strains since the adoption of ACT. Therefore, continuous monitoring of the molecular markers of antimalarial drug resistance in Jazan region is highly recommended.

Plasmodium falciparum histidine rich protein 2 (pfhrp2): an additional genetic marker suitable for anti-malarial drug efficacy trials.

BACKGROUND: Genotyping of the three Plasmodium falciparum polymorphic genes, msp1, msp2 and glurp, has been adopted as a standard strategy to distinguish recrudescence from new infection in drug efficacy clinical trials. However, the suitability of a particular gene is compromised in areas where its allelic variants distribution is significantly skewed, a phenomenon that might occur in isolated parasite populations or in areas of very low transmission. Moreover, observation of amplification bias has diminished the value of glurp as a marker. METHODS: The suitability of the polymorphic P. falciparum histidine-rich protein 2 (pfhrp2) gene was assessed to serve as an alternative marker using a PCR-sequencing or a PCR-RFLP protocol for genotyping of samples in drug efficacy clinical trials. The value of pfhrp2 was validated by side-by-side analyses of 5 admission-recrudescence sample pairs from Yemeni malaria patients. RESULTS: The outcome of the single pfhrp2 gene discrimination analysis has been found consistent with msp1, msp2 and glurp pool genotyping analysis for the differentiation of recrudescence from new infection. CONCLUSION: The findings suggest that under the appropriate circumstances, pfhrp2 can serve as an additional molecular marker for monitoring anti-malarials efficacy. However, its use is restricted to endemic areas where only a minority of P. falciparum parasites lack the pfhrp2 gene.

Epidemiological screening and serotyping analysis of dengue fever in the Southwestern region of Saudi Arabia.

Dengue is an acute systemic viral disease that has been developed globally in both chronic and epidemic transmission periods. Dengue virus (DENV) is a member of the Flavivirus genus of the Flaviviridae family, which endangers public health. Limited studies have been performed in the Saudi Arabia and there are no epidemiological as well as molecular screening of DENV in the Southwestern region and this current study was conducted on the epidemiology of dengue in the Southwestern region of Saudi Arabia. Simultaneously, we have screened the 100 patients for DENV using the real-time reverse transcriptase polymerase chain reaction (RT-PCR) assay. The current study results confirmed that 6637 people from various hospitals and locations in Jazan, Southwestern regions, were enrolled in this study from 2012 to 2020. The overall mean age was 30.02 ±â€¯18.01 years, with 62.8% of males and 37.2% of females enrolled. This study included nearly three-fourths of the Saudi participants and one-fourth of the expatriates, and 56.6% of the positive cases were enrolled. In 2019, the most instances were enrolled, with 44% of positive cases. When screened using the RT-PCR assay, 93% of the positive patients were recruited, according to the quality control analysis. In conclusion, the current study results confirmed the prevalence of DENV was increased drastically since 2012 to 2020. High number of cases were registered prior to the Pandemic. The screening for DENV was performed with RT-PCR assay and NSI antigen should also be implemented to cross-check the results which was previously performed with RT-PCR analysis.

Tuberculosis among people living with HIV/AIDS in Jazan Region, Southwestern Saudi Arabia.

BACKGROUND: Tuberculosis (TB) and human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) infections are leading causes of morbidity and mortality worldwide. People living with HIV/AIDS (PLWHA) are highly susceptible to TB infection and progression to active TB disease. This study aims to determine the proportion and risk factors of TB among PLWHA in Jazan Region, southwestern Saudi Arabia. METHODS: A cross-sectional study was conducted among HIV-infected individuals attending the main referral hospital in Jazan Region during the period 2017-2019. The participants' TB status, CD4+ lymphocyte count, and viral load were assessed. In addition, their demographic and clinical information was collected using a structured questionnaire. RESULTS: A total of 316 HIV-positive individuals aged between 13 and 81 years (75% male and 25% female) were enrolled in this study. Of them, 30 (9.5%; 95% confidence interval [CI]: 5.2, 10.6%) were diagnosed with TB: 46.7% (14/30) had pulmonary TB and 53.3% (16/30) had extrapulmonary TB. The highest proportion of TB-positive PLWHA was found among participants aged 18-30 years (11.6%) and among non-Saudis (14.0%) when compared to other age groups and Saudi participants (7.4%). Multivariate analysis showed that male gender (adjusted odds ratio [AOR] = 4.79; 95% CI = 1.22, 18.74), past medical history (PMH) of TB (AOR = 29.67; 95% CI = 5.31, 164.32), PMH of other RTIs (AOR = 5.86; 95 % CI = 2.14, 16.06), CD4+ lymphocyte count of <200 cells/mm³ (AOR = 4.33; 95% CI = 1.65, 11.36), and viral load of ≥1 × 103 copies/mL (AOR = 5.46; 95% CI = 2.02, 14.77) were the significant risk factors of TB among the studied PLWHA. CONCLUSION: The prevalence of TB/HIV co-infection among the studied population was 9.5%. Therefore, all PLWHA should be screened for TB at every visit to a health facility. The findings highlight that integration of health services for both TB and HIV/AIDS in Saudi Arabia is recommended.

The return of chloroquine-sensitive Plasmodium falciparum parasites in Jazan region, southwestern Saudi Arabia over a decade after the adoption of artemisinin-based combination therapy: analysis of genetic mutations in the pfcrt gene.

This study investigated the polymorphism in the P. falciparum chloroquine resistance transporter (pfcrt) gene 11 years after chloroquine (CQ) cessation in Jazan region, southwestern Saudi Arabia. Two hundred and thirty-five P. falciparum isolates were amplified to detect mutations in the pfcrt gene. The pfcrt 76 T molecular marker for CQ resistance was detected in 66.4% (156/235) of the isolates, while the K76 CQ-sensitive wild type was detected in 33.6%. The pfcrt 74I and pfcrt 75E point mutations were each found to be present in 56.2% of isolates, while only four isolates (1.7%) were found to carry the pfcrt 72S mutation. Moreover, four pfcrt haplotypes were identified as follows: the CVIET triple-allele (56.2%), SVMET double-allele (1.7%) and CVMNT single-allele (8.5%) mutant haplotypes and the CVMNK wild haplotype (33.6%). The analysis also revealed significant associations between the prevalence of mutant pfcrt alleles and haplotypes and the age group, governorate and nationality of the patients as well as the parasitaemia level (p < 0.05). The findings provide evidence of the potential re-emergence of CQ-susceptible P. falciparum strains in Jazan region over a decade after CQ discontinuation, with about one third of the isolates analysed carrying the pfcrt K76 CQ-sensitive wild allele and the CVMNK ancestral wild haplotype. Although the reintroduction of CQ cannot be recommended at present in Saudi Arabia, these findings support the rationale for a potential future role for CQ in malaria treatment. Therefore, continuous molecular and in vitro monitoring mutations of pfcrt polymorphism in Jazan region is highly recommended.

Residual malaria in Jazan region, southwestern Saudi Arabia: the situation, challenges and climatic drivers of autochthonous malaria.

BACKGROUND: Saudi Arabia and Yemen are the only two countries in the Arabian Peninsula that are yet to achieve malaria elimination. Over the past two decades, the malaria control programme in Saudi Arabia has successfully reduced the annual number of malaria cases, with the lowest incidence rate across the country reported in 2014. This study aims to investigate the distribution of residual malaria in Jazan region and to identify potential climatic drivers of autochthonous malaria cases in the region. METHODS: A cross-sectional study was carried out from 1 April 2018 to 31 January 2019 in Jazan region, southwestern Saudi Arabia, which targeted febrile individuals attending hospitals and primary healthcare centres. Participants' demographic data were collected, including age, gender, nationality, and residence. Moreover, association of climatic variables with the monthly autochthonous malaria cases reported during the period of 2010-2017 was retrospectively analysed. RESULTS: A total of 1124 febrile subjects were found to be positive for malaria during the study period. Among them, 94.3 and 5.7% were infected with Plasmodium falciparum and Plasmodium vivax, respectively. In general, subjects aged 18-30 years and those aged over 50 years had the highest (42.7%) and lowest (5.9%) percentages of malaria cases. Similarly, the percentage of malaria-positive cases was higher among males than females (86.2 vs 13.8%), among non-Saudi compared to Saudi subjects (70.6 vs 29.4%), and among patients residing in rural rather than in urban areas (89.8 vs 10.2%). A total of 407 autochthonous malaria cases were reported in Jazan region between 2010 and 2017. Results of zero-inflated negative binomial regression analysis showed that monthly average temperature and relative humidity were the significant climatic determinants of autochthonous malaria in the region. CONCLUSION: Malaria remains a public health problem in most governorates of Jazan region. The identification and monitoring of malaria transmission hotspots and predictors would enable control efforts to be intensified and focused on specific areas and therefore expedite the elimination of residual malaria from the whole region.

Genetic Diversity and Prevalence of Giardia duodenalis in Qatar.

Background: Giardia duodenalis is a common human intestinal parasite worldwide, and the causative agent of diarrhea, with the severity of disease ranging from asymptomatic to intense and debilitating infection. G. duodenalis is known to consist of eight genetically distinct assemblages, named from A to H. No data available on the genotypes and genetic diversity of G. duodenalis circulating in Qatar. Methods: We genotyped 54 human Giardia isolates, collected from asymptomatic immigrants in Qatar, using a multilocus genotyping (MLGs) tool. We also investigated relationships between the subjects' genotypes and their demographic data. Results: Genomic DNA from 54 isolates were tested by PCR and sequence analysis at three loci: glutamate dehydrogenase (gdh), ß-giardin (bg) and triose phosphate (tpi)). Assemblage A was identified in nine (16.67%), assemblage B in thirty (55.55%), and a mixture of assemblages A+B in fifteen (27.78%) isolates. All assemblage A isolates, genotyped in different loci, were assigned to sub-assemblage AII, and six of them had MLGs AII-1 while one new MLG was identified in two isolates. Sequences of assemblage B isolates have high level of genetic diversity and high presence of heterogeneous peaks, especially within the gdh gene. No significant associations between genotypes and the immigrants' demographic data were found due to the extensive number of new variants. Conclusions: MLGs was used herein to genotype 54 immigrant Giardia isolates. The high level of genetic variability found in our isolates hampered MLGs determination, more investigations are now required to consolidate our findings, and to enable a comprehensive understanding of the diversity within G. duodenalis assemblage B isolates.

Knowledge and attitude towards cutaneous leishmaniasis among rural endemic communities in Shara'b district, Taiz, southwestern Yemen.

BACKGROUND: Cutaneous leishmaniasis (CL), a neglected tropical disease, represents a significant public health problem in many endemic countries including Yemen. The ongoing armed conflict that started in March 2015 has had a negative impact on the entire healthcare system as well as on infectious disease control programmes. Therefore, this cross-sectional study aimed to assess knowledge and attitude towards CL among rural endemic communities in southwestern Yemen. METHODS: Five hundred households in five areas of Shara'b district of Taiz governorate were randomly selected to participate in a quantitative survey. A pretested structured questionnaire was used to collect data on the sociodemographic characteristics of the participants, their knowledge and attitude towards CL and their knowledge on the sand fly vector. RESULTS: The analysis was conducted on a final sample of 466 individuals (62.7% males and 37.3% females) aged between 18 and 70 years. Among the participants, 21.5% were non-educated while 39.7 and 20.8% had completed secondary school and tertiary education, respectively. Although the participants were aware of CL, about three quarters (77.7%) of them had poor overall knowledge about disease transmission, clinical presentation, treatment, and prevention. Interestingly, approximately half of the participants (49.1%) were able to differentiate sand flies from other flies and mosquitoes. However, only 14.8% of the participants knew about the role of the phlebotomine sand fly in the transmission of CL. Only 36.6% believed that CL can be prevented and 49.6% had a negative attitude towards the disease. Univariate and multivariate analyses showed that age and gender were the significant determinants of knowledge about CL and the sand fly vector among the studied population. CONCLUSION: A poor level of knowledge about the different epidemiological aspects of CL was found among rural CL-endemic communities in Taiz. This factor, together with the major collapse of the healthcare infrastructure due to the ongoing civil war in Yemen, may be contributing to the continued endemicity of CL in the governorate. It is therefore recommended that health education on CL transmission and prevention should be provided to the targeted communities.

Quality and readability of web-based Arabic health information on COVID-19: an infodemiological study.

BACKGROUND: This study sought to assess the quality and readability of web-based Arabic health information on COVID-19. METHODS: Three search engines were searched on 13 April 2020 for specific Arabic terms on COVID-19. The first 100 consecutive websites from each engine were analyzed for eligibility, which resulted in a sample of 36 websites. These websites were subjected to quality assessments using the Journal of the American Medical Association (JAMA) benchmarks tool, the DISCERN tool, and Health on the Net Foundation Code of Conduct (HONcode) certification. The readability of the websites was assessed using an online readability calculator. RESULTS: Among the 36 eligible websites, only one (2.7%) was HONcode certified. No website attained a high score based on the criteria of the DISCERN tool; the mean score of all websites was 31.5 ± 12.55. As regards the JAMA benchmarks results, a mean score of 2.08 ± 1.05 was achieved by the websites; however, only four (11.1%) met all the JAMA criteria. The average grade levels for readability were 7.2 ± 7.5, 3.3 ± 0.6 and 93.5 ± 19.4 for the Flesch Kincaid Grade Level, Simple Measure of Gobbledygook, and Flesch Reading Ease scales, respectively. CONCLUSION: Almost all of the most easily accessible web-based Arabic health information on COVID-19 does not meet recognized quality standards regardless of the level of readability and ability to be understood by the general population of Arabic speakers.