Herpesvirus May Play Role in Central Nervous System Diseases
Scientists have discovered evidence suggesting a herpesvirus may be responsible for some cases of meningitis and encephalitis. Researchers from the New York State Department of Public Health, Albany and SUNY, Albany report their findings in the December 2007 issue of the Journal of Clinical Microbiology.
Human herpesvirus 6 (HHV-6) is one of the most prevalent in humans. There are two variants of HHV-6, HHV-6A and HHV-6B which is attributed to a common childhood disease characterized by a high fever and rash. Studies indicate that by age 3 the majority of children have been infected by HHV-6, after which the virus persists in the salivary glands into adulthood. The virus may remain dormant or reactivate in immunocompetent or immunocompromised individuals.
Over a span of four years, researchers collected specimens from patients hospitalized with symptoms of encephalitis and meningitis, and tested them for the presence of HHV-6. The majority of the specimens were taken from cerebrospinal fluid and some of the symptoms exhibited by the patients include fever, altered mental status, and abnormal CSF profile, as well as seizures in those ages 3 and under. Results showed that 26 specimens from 24 patients were positive for HHV-6, of which 20 were identified as the HHV-6B strain. Forty-two percent of the patients were age 3 or under, possibly indicating primary infection, while the remaining patients ranging from 4 to 81 years old were probably experiencing viral reactivation.
"The detection of HHV-6 in specimens from patients diagnosed with encephalitis or meningitis, in the absence of a positive PCR result for other agents, strongly suggests a role for HHV-6 in the pathogenesis of these central system diseases," say the researchers.
(N.P. Tavakoli, S. Nattanmai, R. Hull, H. Fusco, L. Dzigua, H. Wang, M. Dupuis. 2007. Detection and typing of human herpesvirus 6 by molecular methods in specimens from patients diagnosed with encephalitis or meningitis. Journal of Clinical Microbiology, 45. 12: 3972-3978.)
Novel Virus Identified in Endangered Species May Represent Evolution of Two Major Virus Families
The near extinction of the western barred bandicoot has led to the identification of a novel virus exhibiting characteristics of two ancient virus families. The researchers from Murdoch University, Perth, Western Australia, and the University of Leuven, Belgium report their findings in the December 2007 issue of the Journal of Virology.
The western barred bandicoot (WWB), an Australian marsupial once commonly found across western and southern Australia, is now endangered throughout parts of the country and already extinct on the mainland. While promoting conservation efforts, researchers discovered a debilitating disease affecting the species causing full body lesions.
Papillomaviruses (PVs) and polyomaviruses (PyVs) are known to infect human, mammalian, and avian species. They were previously considered subunits of the Papovaviridae family, however they are currently recognized as two separate virus families due to significantly different genome sizes and organizations. In the study researchers analyzed skin swabs taken from the lesions of infected WWBs and identified a novel virus exhibiting properties of both the Papillomaviridae and Polyomaviridae family. They have designated this new prototype the bandicoot papillomatosis carcinomatosis virus type 1 (BPCV1).
"BPCV1 may represent the first member of a novel virus family, descended from a common ancestor of the papillomaviruses and polyomaviruses recognized today," say the researchers. "The discovery of the virus could have implications for the current taxonomic classification of Papillomaviridae and Polyomaviridae and can provide further insight into the evolution of these ancient virus families."
L. Woolford, A. Rector, M.V. Ranst, A. Ducki, M.D. Bennett, P.K. Nicholls, K.S. Warren, R.A. Swan, G.E. Wilcox, A.J. O'Hara. 2007. A novel virus detected in papillomavirus and carcinomas of the endangered western barred bandicoot (Perameles bougainville) exhibits genomic features of both the Papillomaviridae and Polyomaviridae. Journal of Virology, 81. 24: 13280-13290.)