Comparative analysis of disease pathogenesis and molecular mechanisms of New World and Old World arenavirus infections

University of Minnesota.
Journal of General Virology (Impact Factor: 3.18). 09/2013; 95(Pt_1). DOI: 10.1099/vir.0.057000-0
Source: PubMed


Arenaviruses can cause fatal human haemorrhagic fever (HF) diseases for which vaccines and therapies are extremely limited. Both the New World (NW) and Old World (OW) groups of arenaviruses contain HF-causing pathogens. Although these two groups share many similarities, important differences with regards to pathogenicity and molecular mechanisms of virus infection exist. These closely related pathogens share many characteristics, including genome structure, viral assembly, natural host selection, and the ability to interfere with innate immune signalling. However, members of the NW and OW viruses appear to use different receptors for cellular entry as well as different mechanisms of virus internalization. General differences in disease signs and symptoms and pathological lesions in patients infected with either the NW or OW arenaviruses are also noted and discussed herein. While both the OW Lassa virus (LASV) and the NW Junin (JUNV) can cause disruption of the vascular endothelium, which is an important pathological feature of HF, the immune responses to these related pathogens seem to be quite distinct. Whereas LASV infection results in an overall generalized immune suppression, patients infected with JUNV seem to develop a cytokine storm. Additionally, the type of immune response required for recovery and clearance of the virus is different between the NW and OW infections. These differences may be important to allow the viruses to evade host immune detection. Understanding these differences will aid the development of new vaccines and treatment strategies against deadly haemorrhagic fever viral infections.

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    • "tavirus - infected patients in the Old and New World include high fever , hemorrhages , thrombocytopenia , abdominal pain , flu - like symptoms , and finally organ failure – symptoms known to be also caused by many other hemorrhagic fever viruses including arena - , filo - , and flaviviruses ( Kortepeter et al . , 2011 ; Heinz and Stiasny , 2012 ; McLay et al . , 2014 ) . Recent outbreaks of zoonotic diseases , like MERS coronavirus on the Arabian Peninsula ( de Groot et al . , 2013 ) or Ebola virus in West Africa ( Baize et al . , 2014 ) , demonstrate a high necessity for intensive studies of highly pathogenic zoonotic viruses in order to be prepared for their emergence and major outbreaks . Here we"
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