Global Epidemic of Ebola Virus Disease and the Importation Risk into China: An Assessment Based on the Risk Matrix Method

Objective To analyze the global epidemic status of the Ebola virus disease(EVD) and assess the importation risk into China.Methods Data from World Health Organization reports were used. We described the global epidemic status of EVD from 1976–2021, and assessed and ranked the importation risk of EVD from the diseaseoutbreaking countries into China using the risk matrix and Borda count methods, respectively.Results From 1976–2021, EVD mainly occurred in western and central Africa, with the highest cumulative number of cases(14,124 cases) in Sierra Leone, and the highest cumulative fatality rate(85%) in the Congo. Outbreaks of EVD have occurred in the Democratic Republic of the Congo and Guinea since 2018. The importation risk into China varies across countries with outbreaks of disease.The Democratic Republic of the Congo had an extremely high risk(23 Borda points), followed by Guinea and Liberia. Countries with a moderate importation risk were Nigeria, Uganda, Congo, Sierra Leone,Mali, and Gabon, while countries with a low importation risk included Sudan, Senegal, and Co te d’Ivoire.Conclusion China is under the risk of EVD importation with the globalization and severe epidemic status of EVD. Key attention need to be paid to the Democratic Republic of the Congo, Guinea, and Liberia. Therefore, it is necessary to prevent and prepare in advance for importation risk in China.

EBV相关噬血细胞综合征并发急性肾损伤患者的临床特点分析

目的:分析EB病毒(EBV)感染相关噬血细胞综合征(HLH)患者并发急性肾损伤(AKI)的临床特点。方法:收集2014年1月至2020年12月期间于本院住院治疗的EBV相关HLH患者,对患者的临床特征、治疗、并发AKI情况及预后进行回顾性分析。结果:本研究中EBV-HLH患者的AKI发生率为65.5%,28 d死亡率为15.3%。与未发生AKI组患者比较,并发AKI的EBV-HLH患者的胆红素、乳酸脱氢酶、肌酐、尿素氮、β_(2)-微球蛋白(β_(2)-MG)的水平更高,凝血功能更差,可溶性白细胞介素-2受体(sCD25)更低。AKI组患者接受化疗、移植、机械通气、应用血管活性药物的比例更高,住院时间更长,住院病死率及28 d病死率更高。AKI患者按照改善全球肾脏预后组织(KDIGO)分级进行亚组分析,白细胞、胆红素、白蛋白、肌酐、尿素氮、β_(2)-MG、活化部分凝血活酶时间(APTT)、凝血酶原时间(PTA)水平更能反应患者病情的严重程度,KDIGO 2级和3级的患者接受移植、利尿剂、脏器支持(机械通气、应用血管活性药物、肾替代治疗)和入住重症监护病房的比例更高,住院病死率和28 d病死率更高。回归分析发现,肌酐、β_(2)-MG、APTT、移植、化疗是AKI发生的独立危险因素;应用血管活性药物既是AKI发生的独立危险因素,也是28 d死亡的独立危险因素;化疗、住院时间、HGB及纤维蛋白原水平是28天死亡的保护性因素。结论:EBV-HLH患者的AKI发生率高,进展为重症病死率高,应早期重视、加强关注,从而进行早期治疗以改善预后。

儿童EBV传染性单核细胞增多症细胞因子IL-6、γ-IFN、IL-10的改变

目的探讨EB病毒(EBV)感染的传染性单核细胞增多症(IM)患儿淋巴细胞亚群和细胞因子IL-6、γ-IFN、IL-10的变化及临床意义。方法选择2018年9月至2020年8月苏州大学附属儿童医院感染科收治的EBV感染的IM患儿100例作为病例组。同期在苏州大学附属儿童医院儿童保健科体检的健康儿童60名作为对照组。采用流式细胞术和酶联免疫吸附试验分别检测IM患儿及对照组的外周血淋巴细胞亚群和细胞因子(IL-6、IL-10、γ-IFN)水平。结果病例组细胞因子IL-6、IL-10、γ-IFN高于对照组(P<0.05或0.001)。病例组CD3^(+)、CD3^(+)CD8^(+)百分比高于对照组,而CD3^(+)CD4^(+)、CD19^(+)CD23^(+)、CD3^(-)CD(16+56)+、CD3^(-)CD19^(+)百分比、CD4^(+)/CD8^(+)比值低于对照组,两组差异均有统计学意义(P<0.001)。两组间异型淋巴细胞百分比、WBC、ALT、AST、LDH差异均有统计学意义(P<0.05或0.01)。病例组IL-6与异型淋巴细胞百分比、WBC、血浆EBV-DNA病毒载量、ALT、LDH无相关性(P>0.05),与AST呈正相关(P<0.05)。病例组IL-10与异型淋巴细胞百分比、WBC、血浆EBV-DNA病毒载量、ALT、AST、LDH均无相关性(P>0.05)。病例组γ-IFN与异型淋巴细胞百分比、WBC、ALT、LDH无相关性(P>0.05),与血浆EBV-DNA病毒载量和AST呈正相关(P<0.05)。病例组IL-6与CD3^(+)、CD3^(+)CD8^(+)百分比呈负相关(P<0.05或0.001),与CD3^(+)CD4^(+)、CD3^(-)CD19^(+)百分比、CD4^(+)/CD8^(+)呈正相关(P<0.05或0.001),与CD19^(+)CD23^(+)、CD3^(-)CD(16+56)^(+)百分比无相关性(P>0.05)。病例组IL-10与CD19^(+)CD23^(+)、CD3^(-)CD19^(+)百分比呈正相关(P<0.05),与CD3^(+)呈负相关(P<0.05),与CD3^(+)CD4^(+)、CD3^(+)CD8^(+)、CD3^(-)CD(16+56)^(+)百分比、CD4^(+)/CD8^(+)无相关性(P>0.05)。病例组γ-IFN与CD3^(+)、CD3^(+)CD8^(+)百分比呈负相关(P<0.05),与CD19^(+)CD23^(+)、CD3^(+)CD4^(+)、CD3^(-)CD(16+56)^(+)、CD3^(-)CD19^(+)百分比、CD4^(+)/CD8^(+)无相关性(P>0.05)。结论EBV感染的传染性单核细胞增多症患儿的免疫改变和炎症反应与疾病的发生、发展有关,IL-6、IL-10、γ-IFN参与传染性单核细胞增多症的免疫发病过程。

1例异基因造血干细胞移植术后并发CMV和EBV共激活患儿的护理

异基因造血干细胞移植(allogeneic hematopoietic stem cell transplantation,allo-HSCT)是指将健康人的造血干细胞移植至病人体内,目的是帮助其重建造血和免疫功能。越来越多的研究已经证实allo-HSCT是地中海贫血病人能够重新获得生命的主要治疗方法,目前在各大移植中心广泛开展。

Ebola virus disease: past, present and future

Ebola virus disease is one of the most deadly ailments known to mankind due to its high mortality rate(up to 90%) accompanying with the disease. Ebola haemorrhagic fever(EHF) is an infectious disease of animal that can be transmitted to both human and non-human primates. The first epidemic of EHF occurred in 1976 in the Democratic Republic of the Congo. The incubation period of ebola is less than 21 days. Ebola virus infections are depicted by immune suppression and a systemic inflammatory response that leads to damage of the vascular, coagulation and immune systems, causing multi-organ failure and shock. Five genetically distinct members of the Filoviridae family responsible for EHF are as follows: Zaire ebolavirus, Sudan ebolavirus, C?te d'Ivoire ebolavirus, Bundibugyo ebolavirus and Reston ebolavirus. The ongoing 2014 West Africa ebola epidemic has been considered as the most serious panic in the medical field with respect to both the number of human cases and death toll. The natural host for ebola virus is unknown, thus it is not possible to carry out programs to regulate or abolish virus from transmission to people. The ebola virus infection provides little chance to develop acquired immunity causing rapid progression of the disease. It is pertinent to mention that at present, there is no antiviral therapy or vaccine that is helpful against ebola virus infection in humans. The impediment of EHF necessitates much better understanding of the epidemiology of the disease, particularly the role of wildlife, as well as bats, in the spread of ebola virus to humans.

Nucleoprotein-based indirect enzyme-linked immunosorbent assay(indirect ELISA) for detecting antibodies specific to Ebola virus and Marbug virus

Full-length nucleoproteins from Ebola and Marburg viruses were expressed as His-tagged recombinant proteins in Escherichia coli and nucleoprotein-based enzyme-linked immunosorbent assays(ELISAs) were established for the detection of antibodies specific to Ebola and Marburg viruses. The ELISAs were evaluated by testing antisera collected from rabbit immunized with Ebola and Marburg virus nucleoproteins. Although little cross-reactivity of antibodies was observed in antiEbola virus nucleoprotein rabbit antisera, the highest reactions to immunoglobulin G(Ig G) were uniformly detected against the nucleoprotein antigens of homologous viruses. We further evaluated the ELISA's ability to detect antibodies to Ebola and Marburg viruses using human sera samples collected from individuals passing through the Guangdong port of entry. With a threshold set at the mean plus three standard deviations of average optical densities of sera tested, the ELISA systems using these two recombinant nucleoproteins have good sensitivity and specificity. These results demonstrate the usefulness of ELISA for diagnostics as well as ecological and serosurvey studies of Ebola and Marburg virus infection.

Ebola Virus Disease: General Characteristics, Thoughts, and Perspectives

In December 2013, a new round of Ebola virus disease （EVD） first occurred in a remote countryside of Guinea and then spread in Guinea, Liberia, Sierra Leone, and Nigeria of West Africa. EVD, caused by Ebolavirus and previously known as Ebola hemorrhagic fever, is an acute infectious disease with fatality rates up to 90%. As of August 22, 2014, the number of suspected and confirmed cases was 2615, causing 1427 deaths[I]. On August 8, 2014, World Health Organization announced the current outbreak in West Africa as an international public health emergency. The global epidemic tendency remains ambiguous to date. In recent years, China closely collaborates with West Africa in labor, business, overseas education, and also sends aid medical team there. Thus, the risk of importing the disease cannot be ignored. We conduct this literature review of epidemiology, pathogen, prophylaxis, and treatment to provide evidence for controlling the risk and carrying out effective interventions.

CHARACTERIZATION OF A HUMAN HERPES VIRUS－6（HHV－6） AND EPSTEIN－BARR VIRUS（EBV） ASSOCIATED LEUKEMIC CELL LINE，J6－1

This report characterizes the J6-1 cell line derived from a Chinese acute myelomonocytic leukemia patient and previously reported to be associated with EBV. These studies showed that J6-1 cells were also infected with HHV-6 as demonstrate at the DNA level by PCR and Southern blot hybridization and by expression of HHV-6 early membrane antigen on the J6-1 cell surface. Further characterization showed J6-1 was co-infected with EBV type 2. Generally, cells infected with EBV type 2 do not grow well in vitro. However, J6-1 , although difficult to maintain in vitro, has been grown for 15 years. Possibly, co-infection with HHV6 confers this property. In this regard, J6-1 cells exhibited density dependent growth which could be inhibited with an anti-HHV-6-MA monoclonal antibody(MAb). In contrast, anti-HHV-6-VCA MAb stimulated the J6-1 cell proliferation. Electron microscopic analysis showed that, morphologically, there were two types of J6-1 cell, one with lymphoblastoid features and one with a monocytoid appearance. Accordingly, the flow profile of the J6-1 cell line showed heterogeneity. with two populations comprised of CD15-, CD19+ cells with low light scatter(small cells) and a population with greater light scatter(larger cells) which was CD15+ , CD19+. The population was negative for progenitor cell markers(CD33, 34 ), and T cell markers. Southern analysis showed no T cell receptor rearrangement, however there was a clonal JH and kappa light chain expressing population. Glycocytochemical analysis showed several endogenous lectin receptors on the J6-1 cell surface: BSA-Xylose, BSA-Rhamnose, BSAGal. BSA-Lac. This cell line shares many characteristics with other monocytic/ lymphoblastoid cell lines isolated elsewhere and provides circumstantial evidence linking Herpes viruses, as least as co- factors,to leukemia cell growth.

Ebola virus disease: From epidemiology to prophylaxis

The outbreak of Ebola virus disease(EVD) continues to spread through West Africa. Since the first reported EVD in March 2014, the number of cases has increased rapidly, with the fatality rate of >50%. The most prevalent Ebola virus belongs to the species of Zaire ebolavirus, with a mortality rate as high as 90%. Although there were introduced cases in other continents, Africa is the endemic area where fruit bats and apes are suspected to be Ebola virus carriers. The virus might be transmitted from the host animals to humans if humans consume relative raw and contaminated meats; however, human-to-human transmission via close contact is the major route of current outbreaks. EVD happens at any seasons and affected people of any race in any age groups. Direct contact with body fluids of EVD patients and living in the contaminated environment greatly increase the risk of being infected. Transmission viaaerosol is less possible but the transmission via droplet is possible in humans. Thus, health care providers are facing danger of getting Ebola virus infection. So far, there are limited vaccines, drugs and/or therapies to prevent Ebola virus infection or treat EVD. Medical workers should follow the current standard prophylactic procedures. Military forces can orchestrate efficient care to mass EVD casualties. Although it is necessary to speed up the pace of developing effective vaccine and therapeutics for the prevention and treatment of EVD, public health prophylaxis is the most important issue at present to control the spread of this disease cost-effectively.

The Ebola virus:a review of progress and development in research

The Ebola virus was identified in the year 1976 and has caused periodic outbreaks in West African countries.The disease has a case fatality rate up to 90%.Ebola has been classified as a biosafety level four pathogen and there is no currently approved vaccine or treatment for the virus.However,remarkable progress has been demonstrated by researchers in understanding the pathogenicity of the Ebola virus.Several animal models have been cultivated to develop diagnostics,vaccines and therapeutic drugs.

Detection and Analysis of Ebola Virus in Sierra Leone-China Friendship Biosafety Laboratory from March 11 to April 20, 2015

Ebola virus disease reemerged in Western Africa in 2014.Chinese Center for Disease Control and Prevention dispatched the first Ebola virus（EBOV）detection team to run newly established Sierra Leone-China Friendship Biological Safety Laboratory.The aims of study were to understand epidemiology,clinical manifestations and survival time of EBOV in patient＇s blood.A total of 913specimens were tested between March 11 and April20, 2015. EBOV positivity occurred in 7.37% of the blood and 0.53% in throat swabs.

The initial results of Epstein-Barr virus (EBV)-encoded latent membrane protein-1 (LMP-1) for screening nasopharyngeal carcinoma (NPC)

Objective: Early diagnosis of nasopharyngeal carcinoma (NPC) is an important method to improve the survival rate.However,the sensitivity and specificity of the screening protocols which was widely used in clinic now are considered to be unsatisfactory.Epstein-Barr virus (EBV)-encoded latent membrane protein-1 (LMP-1) is one of the proteins that have been suggested to be a classic oncogene with transformation properties.The current study set out to discuss the clinical significance of LMP-1 on the screening of NPC.Methods: Three hundred patients who visited our institution (Department of Radiation Oncology,Fujian Provincial Cancer Hospital,Fuzhou,China) with ENT symptoms between 2007 and 2008 were involved in this study,and all of them were agreed to be involved in this investigation.Not only did they undergo nasopharyngeal swab to obtain cells for the LMP-1 polymerase chain reaction (PCR) analysis,but also nasopharyngeal biopsy were taken to identify the diagnosis.Results: An amount of DNA that was sufficient for PCR was extracted from 243 (81%) swab samples,the positive rate of LMP-1 of those with non-nasopharyngeal carcinoma was 3.85% (4/108),which was much lower than those with nasopharyngeal carcinoma (P < 0.05).By detecting LMP-1 in nasopharyngeal swabs,NPC was diagnosed with a sensitivity of 88.15% (119 of 135 patients),specificity of 96.30% (104 of 108 patients),a positive predictive value of 95.2% (119 of 123 patients),a negative predictive value of 86.67% (104 of 120 patients),accuracy of 91.77%,and Youden index of 84.45%.Conclusion: The nasopharyngeal swab coupled with PCR-based EBV LMP-1 detection have high sensitivity and specificity,and also good repeatability,it could serve as part of the screening program for high-risk populations.

Ebola virus disease: Recent advances in diagnostics and therapeutics

Ebola virus disease(EVD)is associated with haemorrhagic fever in humans and nonhuman primates,with a high rate of fatality(up to 90%).Some outbreaks in human history have proven the lethality of EVD.The recent epidemic of 2014 and 2015 in West Africa was the deadliest of all time(11 284 deaths).To understand the transmission dynamics,we have reviewed the epidemiology of EVD to date.The absence of any licensed vaccines or approved drugs against Ebola virus(EBOV)further highlights the severity and crisis level of EVD.Some organizations(public and private)are making considerable efforts to develop novel therapeutic approaches or vaccines to contain the outbreak of EBOV shortly.Here,we summarized the various potential drugs and vaccines(undergoing multiple phases of clinical trials)that have arisen as an alternative against EBOV,and we highlighted the numerous issues and limitations hindering this process.Alternatively,an increasing focus on strengthening the medical and civic health structure could provide speedy benefits in containing the spread of EVD,as well as offer a resilient foundation for the deployment of novel drugs and vaccines to the affected countries,once such drugs and vaccines become available.

Genetic diversity in Ebola virus:Phylogenetic and in silico structural studies of Ebola viral proteins

Objective:To explore the genetic diversity and the modification of antibody response in the recent outbreak of Ebola Virus.Methods:Sequences retrieved from public databases,the selective pressure analysis and the homology modelling based on the all protein(nucleoprotein.VP35,VP40.soluble glycoprotein,small soluble glycoprotein.VP30,VP24 and polymerase) were used.Results:Structural proteins VP24.VP30.VP35 and VP40 showed relative conserved sequences making them suitable target candidates for antiviral treatment.On the contrary,nucleoprotein.polymerase and soluble glycoprotein have high mutation frequency.Conclusions:Data from this study point out important aspects of Ebola virus sequence variability that for epitope and vaccine design should be considered for appropriate targeting of conserved protein regions.

Phosphorylation sites within Ebola virus nucleoprotein

To understand the infection process, the viral multiplication and entry to the cell is widely studied. The Ebola virus nucleoprotein is the important problem for the pathological process. Focusing on the specific biological process, the post translational modification is needed. Here, the authors used the bioinformatics study to find the phosphorylation sites within the Ebola virus nucleoprotein and could identify many new sites.

Obstetrical Surgery in the Context of Ebola Virus Disease (Ebola) in Guinea: Lessons Learned from 2 Cases

In this manuscript, the authors have studied obstetrical surgery in the context of Ebola virus disease in Guinea. No protocol recommends childbirth outside of Ebola treatment center, although it has no technical platform and no qualified providers in this area. These were unknown MVE cases in pregnant women/parturient women aged 25 and 40 years, with no education, who were confirmed in the RT-PCR test after surgical management. To fight Ebola virus transmission, traditional protection protocols must be strengthened. Training, supervision and monitoring of providers are key elements for the protection of staff in the event of an EVD outbreak. Improving working conditions and strengthening hand washing, usage of PPE/EPP, decontamination of equipment with 0.5% chlorine solution, hygiene of premises, immunization of personnel involved, are effective measures to combat EVD.

Knowledge, Attitudes and Preventive Practices on Ebola Virus Disease in the Kintampo Districts of Ghana

This study describes community members’ knowledge of Ebola Virus Disease (EVD), their attitudes and preventive practices. A mixed methods approach was used. A random sample of 1028 community members aged 15 - 65 years was interviewed in a quantitative survey. This was complemented with a qualitative study involving 24 opinion leaders who were carefully selected. The study was conducted in Kintampo North and South districts of Ghana from August 2014 to October 2014. 83% of respondents had heard of EVD, but 62.5% did not know the duration between the time of infection and onset of clinical symptoms. The most popular symptom mentioned spontaneously was bleeding through body orifices (48.6%). Majority of respondents mentioned handshake or skin contact as a mode of transmission (57.3%) and reduced contact with bats as a means to prevent the spread of EVD (58.1%). Knowledge of transmission of body fluids such as faeces, blood or urine was low (<10%), though this varied significantly by socio-demographic group. Majority (94%) of respondents acknowledged that EVD was a serious disease, however, only 58% saw themselves at risk. Current preventive behaviours included: improved hand hygiene (83%) and avoidance of handshakes and physical contact with people (81%). Community members in the Kintampo districts have high level of awareness of EVD, but important gaps in knowledge of EVD still exist, especially concerning body fluids as a mode of transmission. There is the need to intensify educational messages as part of Ghana’s preparedness towards a potential EVD outbreak.

Identification of active pocket and protein druggability within envelope glycoprotein GP2 from Ebola virus

The drug searching for combating the present outbreak of Ebola virus infection is the urgent activity at present.Finding the new effective drug at present must base on the molecular analysis of the pathogenic virus.The in-depth analysis of the viral protein to find the binding site,active pocket is needed.Here,the authors analyzed the envelope glycoprotein GP2 from Ebola virus.Identification of active pocket and protein draggability within envelope glycoprotein GP2 from Ebola virus was done.According to this assessment,7 active pockets with varied draggability could be identified.

A Case Report of Pediatric Epstein Barr Virus (EBV) Related Cholestasis from Al-Adan Hospital, Kuwait

Infectious mononucleosis is an acute illness due to Epstein Barr virus infection, which occurs commonly in young adults. Liver involvement in acute EBV infection occurs in up to 95% of patients between the 6th and 15th day of illness and is usually mild [1]. Here we report on a 7-year-old girl treated by Gastroenterology, Hepatology, and Nutrition Unit of Al-Adan Hospital pediatric Department, presented with prolonged fever, lymphadenopathy, generalized edema, hyperbilurubi- nemia and elevated liver enzymes secondary to EBV infection. This case represents a rare presentation of common viral infection in pediatric population.

Synthetic Biology Construct of Ebola Virus in Bacteria Surrogate Is Stable and Safe for Rapid Detection Studies in a BSL-2 Laboratory Setting

Rapid detection of virulent pathogens during an outbreak is critical for public health advisories and control of the disease in a population. While many molecular techniques for point of care and clinical diagnosis abound, the US experience with the COVID-19 testing in the early stages of the pandemic underscores the critical importance of determining the appropriate target gene(s) with in-built controls that reliably detect pathogens with high sensitivity and specificity. Assays and research for diagnostics and therapy could be slowed during an epidemic because access to the required BSL-3 and BSL-4 laboratories are limited. So, during the 2014 West Africa Ebola outbreak, we tested the hypothesis that using synthetic cDNA of Ebolavirus in a bacteria surrogate (fit for all lab settings), would remain unmutated and safe after several generations, serving as an effective positive control in research settings, self test and point-of-care detection platforms. Primers were designed for the detection and quantification of the nucleoprotein (NP) gene of the 2014 Makona Ebola strain (KR781608.1, 733 - 1332 bp). To test the stability of artificially inserted translation arrest in the Orf of the model gene, it was edited to include three STOP codons in the RNA transcript using SNAP GENE. The segment was then spliced into a high copy number plasmid, cloned into One ShotTM TOP10 Escherichia coli (Invitrogen), and tested for stability and safety by periodic subculture, extraction and sequencing. Unlike COVID-19, rapid detection of blood-borne etiologies like Ebola requires optimized protocols for blood matrix. Using real-time PCR and newly designed primer pairs, the EBOV surrogate was detected and enumerated in human blood and regular broth and buffers. Based on aligned sequence analysis, the EBOV synthetic NP gene was stable (>99.9999% similarity coefficient) for at least 3 months. Detection sensitivity in broth and blood was at least 100 cells/ml or about 5.8 × 103 to 7.3 × 103 virion equivalents per ml. While the developments of transcription-and-replication-competent virus like particles (trVLP) have made it possible to study the infection and replication cycles of virulent pathogens in BSL-2 laboratories, the simplicity of our model and the reproducibility of detection and enumeration show the utility of synthetic bio-components as positive controls for point of care diagnostic tools. The inserted stop codons remained intact after many generations, suggesting that expressed virulent proteins can be easily silenced in synthetic biology models for research in BSL-1 and 2 and a wide range of pathogens. Synthetic bio-components can thereby aid further research by reducing costs and improving safety for workers and stakeholders.