Basic Clinical and Laboratory Features of Filoviral Hemorrhagic Fever
ABSTRACT The filoviruses Marburg and Ebola cause severe hemorrhagic fever (HF) in humans. Beginning with the 1967 Marburg outbreak, 30 epidemics, isolated cases, and accidental laboratory infections have been described in the medical literature. We reviewed those reports to determine the basic clinical and laboratory features of filoviral HF. The most detailed information was found in descriptions of patients treated in industrialized countries; except for the 2000 outbreak of Ebola Sudan HF in Uganda, reports of epidemics in central Africa provided little controlled or objective clinical data. Other than the case fatality rate, there were no clear differences in the features of the various filovirus infections. This compilation will be of value to medical workers responding to epidemics and to investigators attempting to develop animal models of filoviral HF. By identifying key unanswered questions and gaps in clinical data, it will help guide clinical research in future outbreaks.
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ABSTRACT: Hantaviruses are members of the Bunyaviridae family carried by small mammals and causing human hemorrhagic fevers worldwide. In Western Africa, where a variety of hemorrhagic fever viruses occurs, indigenous hantaviruses have been molecularly found in animal reservoirs such as rodents, shrews, and bats since 2006. To investigate the human contact to hantaviruses carried by these hosts and to assess the public health relevance of hantaviruses for humans living in the tropical rainforest regions of Western and Central Africa, we performed a cross-sectional seroprevalence study in the region of Taï National Park in Côte d´Ivoire and the Bandundu region near the Salonga National Park in the Democratic Republic of Congo. Serum samples were initially screened with enzyme-linked immunosorbent assays using nucleoproteins of several hantaviruses as diagnostic antigens. Positive results were confirmed by Western blotting and immunofluorescence testing. Seroprevalence rates of 3.9% (27/687) and 2.4% (7/295), respectively, were found in the investigated regions in Côte d´Ivoire and the Democratic Republic of Congo. In Côte d´Ivoire, this value was significantly higher than the seroprevalence rates previously reported from the neighboring country Guinea as well as from South Africa. Our study indicates an exposure of humans to hantaviruses in West and Central African tropical rainforest areas. In order to pinpoint the possible existence and frequency of clinical disease caused by hantaviruses in this region of the world, systematic investigations of patients with fever and renal or respiratory symptoms are required.Frontiers in Microbiology 05/2015; 6. DOI:10.3389/fmicb.2015.00518 · 3.94 Impact Factor
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ABSTRACT: Viral infections are associated with coagulation disorders. All aspects of the coagulation cascade, primary hemostasis, coagulation, and fibrinolysis, can be affected. As a consequence, thrombosis and disseminated intravascular coagulation, hemorrhage, or both, may occur. Investigation of coagulation disorders as a consequence of different viral infections have not been performed uniformly. Common pathways are therefore not fully elucidated. In many severe viral infections there is no treatment other than supportive measures. A better understanding of the pathophysiology behind the association of viral infections and coagulation disorders is crucial for developing therapeutic strategies. This is of special importance in case of severe complications, such as those seen in hemorrhagic viral infections, the incidence of which is increasing worldwide. To date, only a few promising targets have been discovered, meaning the implementation in a clinical context is still hampered. This review discusses non-hemorrhagic and hemorrhagic viruses for which sufficient data on the association with hemostasis and related clinical features is available. This will enable clinicians to interpret research data and place them into a perspective.Journal of Medical Virology 10/2012; 84(10):1680-96. DOI:10.1002/jmv.23354 · 2.22 Impact Factor
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ABSTRACT: The filoviruses, Ebola virus (EBOV) and Marburg virus (MARV), are highly lethal zoonotic agents of concern as emerging pathogens and potential bioweapons. Antigen-presenting cells (APCs), particularly macrophages and dendritic cells, are targets of filovirus infection in vivo. Infection of these cell types has been proposed to contribute to the inflammation, activation of coagulation cascades and ineffective immune responses characteristic of filovirus hemorrhagic fever. However, many aspects of filovirus-APC interactions remain to be clarified. Among the unanswered questions: What determines the ability of filoviruses to replicate in different APC subsets? What are the cellular signaling pathways that sense infection and lead to production of copious quantities of cytokines, chemokines and tissue factor? What are the mechanisms by which innate antiviral responses are disabled by these viruses, and how may these mechanisms contribute to inadequate adaptive immunity? A better understanding of these issues will clarify the pathogenesis of filoviral hemorrhagic fever and provide new avenues for development of therapeutics.Antiviral research 02/2012; 93(3):416-28. DOI:10.1016/j.antiviral.2012.01.011 · 3.43 Impact Factor