Ebola and other viral haemorrhagic fevers

A lateral flow biosensor based on gold nanoparticles detects four hemorrhagic fever viruses

The pathogen of viral hemorrhagic fever (VHF), which is harmful to human health, is a hemorrhagic fever virus. Clinicians have long needed convenient and sensitive point-of-care rapid diagnostic tests (RDTs) for hemorrhagic fever viruses. Commonly used methods for pathogen detection rely on conventional culture-based tests, antibody-based assays and polymerase chain reaction (PCR)-based techniques. However, these methods are costly, laborious and time-consuming. Herein, we present a simple and sensitive biosensor for the rapid detection of hemorrhagic fever viruses. For this assay, we develop lateral flow biosensors (LFBs) based on magnetic beads and nicking enzyme-assisted isothermal strand-displacement amplification (SDA) for the detection of hemorrhagic fever viruses. The detection limit of this assay is 10 fM.

Correlation between thrombocytopenia and host response in severe fever with thrombocytopenia syndrome

Severe Fever with Thrombocytopenia Syndrome (SFTS) is an emerging infectious disease caused by a novel bunyavirus, SFTS virus (SFTSV), with fatal outcome developed in approximately 17% of the cases. Thrombocytopenia is a hallmark feature of SFTS, and associated with a higher risk of fatal outcome, however, the pathophysiological involvement of platelet in the clinical outcome of SFTS remained under-investigated. In the current study, by retrospectively analyzing 1538 confirmed SFTS patients, we observed that thrombocytopenia was associated with enhanced activation of the cytokine network and the vascular endothelium, also with a disturbed coagulation response. The platelet phenotypes were also extensively altered in the process of thrombocytopenia development of SFTS patients. More importantly, all these disturbed host responses were related to the severity of thrombocytopenia, thus were considered to play in a synergistic way to influence the disease outcome. Moreover, the clinical effect of platelet transfusion was assessed by comparing two groups of patients with or without receiving this therapy. As a result, we observed no therapy effect in altering frequencies of fatal outcome, clinical bleeding development, or dynamic change of platelet count during the hospitalization. It’s suggested that platelet supplementation alone acted a minor role in improving disease outcome, therefore new therapeutic intervention to regulate host response should be proposed. The current results revealed some evidence of interrelationship between platelet count and clinical outcome of SFTS disease from the perspective of activation of the cytokine network, the vascular endothelium, and the coagulation/fibrinolysis system. These evaluations might help to attain a better understanding of the pathogenesis and therapy choice in SFTS.

Thrombocytopenia in SFTSV is a multifactor-process involving a combination of platelet size or morphology alterations, fibrinolysis activation and coagulation abnormalities, increased inflammatory response and endothelial injury. Platelet supplementation alone shows minor role in improving disease, therefore new therapeutic intervention to regulate host response should be proposed.

Ebola virus disease: Essential clinical knowledge

Since its initial outbreak in 1976, Ebola virus disease (EVD) has affected thousands of people, causing severe illness with high mortality rates. In the absence of a vaccine or effective specific treatment, as well as the lack of early diagnostic and detective methods, the EVD outbreak has generated a significant worldwide health concern. Insufficient health-care system resources, deficient infection control measures, and the shortage of appropriate personal protective equipment acted as amplifiers of the outbreak extension, especially in poorly resourced and unprepared communities. Operating on the frontlines, health-care workers must be familiar, not only with the identification of the disease, but also with the ability to protect themselves and initiate the appropriate response. This review seeks to provide essential information required to identify and manage the disease, with an emphasis on pathogenesis, transmission, diagnosis, treatment, and prevention. We conducted a literature search in MEDLINE/PubMed and Google Scholar using the following keywords: "Ebola, Ebola virus disease, Hemorrhagic Fever, Outbreak." We included all types of publications. To augment our study, we searched the reference lists of identified reviews.

Emerging Zoonotic and Vector-Borne Viral Diseases

Many vector-borne and zoonotic diseases are considered to be emerging; since they are either newly reported to cause human disease, or are causing disease in geographical locations or species not previously documented. In the past 15 years, significant outbreaks of Severe Acute Respiratory Syndrome (or SARS) and Middle Eastern Respiratory Syndrome (or MERS), Nipah and Hendra, Ebola virus disease and Zika fever and others have been reported. In this chapter the clinical characteristics, epidemiological aspects, treatment and prevention and information related to the laboratory investigation of important zoonotic and vector-borne diseases that have emerged in the past 10 years, and how this affects children, will be discussed. Furthermore rabies, considered a neglected viral disease with the majority of victims in Africa being children, will also be addressed.

Crimean-Congo haemorrhagic fever in travellers: A systematic review

Background

The recent Ebola epidemic has increased public awareness of the risk of travel associated viral haemorrhagic fever (VHF). International preparedness to manage imported cases Ebola virus infection was inadequate, highlighted by cases of nosocomial transmission. Crimean-Congo haemorrhagic fever (CCHF) is a re-emerging tick-borne VHF centred in the Eurasian region, affecting a large geographical area and with human-to-human transmission reported, especially in the healthcare setting.

Objectives

To systematically review the characteristics of travel associated Crimean-Congo haemorrhagic fever.

Methods

A systematic review of travel-associated cases of CCHF was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement protocol. PubMed, SCOPUS, Science Citation Index (SCI) and ProMED databases were searched for reports published between January 1960 and January 2016. Three independent reviewers selected and reviewed studies and extracted data.

Results

21 cases of travel associated CCHF were identified, of which 12 died (3 outcome unknown) and 4 secondary (nosocomial) infections were reported. Risk occupations or activities for CCHF infection were reported in 8/12 cases when data were available. Travel from Asia to Asia occurred in 9 cases, Africa to Africa occurred in 5 cases, Africa to Europe in 3 cases, Asia to Europe in 2 cases and Europe to Europe in 2 cases.

Conclusion

CCHF related to travel is rare, is generally associated with at risk activities/occupation and is frequently fatal. Key to early diagnosis and prevention of nosocomial transmission is an understanding of CCHF risk factors and the geographical distribution of CCHF. International travel to CCHF endemic areas is increasing and clinicians and laboratory personnel managing returning travellers should maintain a high index of suspicion.

How can health systems be strengthened to control and prevent an Ebola outbreak? A narrative review

The emergence and re-emergence of infectious diseases are now more than ever considered threats to public health systems. There have been over 20 outbreaks of Ebola in the past 40 years. Only recently, the World Health Organization has declared a public health emergency of international concern (PHEIC) in West Africa, with a projected estimate of 1.2 million deaths expected in the next 6 months. Ebola virus is a highly virulent pathogen, often fatal in humans and non-human primates. Ebola is now a great priority for global health security and often becomes fatal if left untreated. This study employed a narrative review. Three major databases - MEDLINE, EMBASE, and Global Health - were searched using both 'text-words' and 'thesaurus terms'. Evidence shows that low- and middle-income countries (LMICs) are not coping well with the current challenges of Ebola, not only because they have poor and fragile systems but also because there are poor infectious disease surveillance and response systems in place. The identification of potential cases is problematic, particularly in the aspects of contact tracing, infection control, and prevention, prior to the diagnosis of the case. This review therefore aims to examine whether LMICs' health systems would be able to control and manage Ebola in future and identifies two key elements of health systems strengthening that are needed to ensure the robustness of the health system to respond effectively.

Ebola: werknemers in de frontlijn

Ebola is de zoveelste zoönose die de Nederlandse samenleving treft binnen een paar jaar tijd. Denk maar aan de Mexicaanse griep, het Schmallenbergvirus, H5N8 aviaire influenza, MERS-CoV16, Q-koorts en de ziekte van Lyme. De schaal waarop Nederlandse UMC’s en andere ketenpartners zich voorbereiden op een mogelijke introductie van ebola is ongeëvenaard. Sinds augustus 2014 houden vele duizenden professionals, beleidsmakers, et cetera, zich intensief bezig met de voorbereidingen. Uniek bij deze ebola-uitbraak is de grote aandacht voor de bedrijfsgeneeskunde. Was er bij eerdere zoönosen minimaal aandacht voor bedrijfsgeneeskundige aspecten, bij ebola zijn veilige arbeidsomstandigheden een centraal thema – terecht, want werknemers staan hier in de frontlijn. Never waste a good crisis . Wellicht is dit een uitgelezen kans om het thema veilige arbeidsomstandigheden en biologische agentia weer eens bij klanten op de agenda te zetten, ook in andere sectoren.