Klassevirus 1, a previously undescribed member of the family Picornaviridae, is globally widespread

Abstract

Background Diarrhea is the third leading infectious cause of death worldwide and is estimated to be responsible for approximately 2 million deaths a year. While many infectious causes of diarrhea have been established, approximately 40% of all diarrhea cases are of unknown etiology. In an effort to identify novel viruses that may be causal agents of diarrhea, we used high throughput mass sequencing to analyze stool samples collected from patients with acute diarrhea. Results Sequences with limited similarity to known picornaviruses were detected in a stool sample collected in Australia from a child with acute diarrhea. Using a combination of mass sequencing, RT-PCR, 5' RACE and 3' RACE, a 6383 bp fragment of the viral genome was sequenced. Phylogenetic analysis demonstrated that this virus was highly divergent from, but most closely related to, members of the genus Kobuvirus . We have tentatively named this novel virus klassevirus 1. We also detected klassevirus 1 by RT-PCR in a diarrhea specimen collected from a patient in St. Louis, United States as well as in untreated sewage collected in Barcelona, Spain. Conclusion Klassevirus 1 is a previously undescribed picornavirus that is globally widespread and present on at least three continents. Further investigations to determine whether klassevirus 1 is a human pathogen are needed.

Non-Polio Enteroviruses, the Neglected and Emerging Human Pathogens:Are we Waiting for the Sizzling Enterovirus Volcano to Erupt?

“…In a few diarrheal patients, bocavirus, torovirus and picobirnavirus have been reported (Jamieson et al, 1998;Jin et al, 2011;Gallimore et al, 1995). A few picornaviruses including enteroviruses have been reported from a small number of sporadic diarrhoeal cases and as part of a few small-scale epidemiological studies (Harada et al, 2009;Harvala and Simmonds, 2009;Holtz et al, 2008Holtz et al, , 2009Nyangao et al, 2006;Kapoor et al, 2008;Patel et al, 1985;Phan et al, 2005;Patil et al, 2009;Yamashita et al, 1993;Rai et al, 2007;Scarcella et al, 2009, Silva et al, 2008, but their association with diarrhoea has not been seriously considered due C Durga Rao to lack of detailed investigations. Further, a great majority of epidemiological studies failed to include enterovirus in the investigations.…”

“…Every child suffers at least one episode of diarrhoea during the first few years of life. Although several infectious agents, viral, bacterial, protozoan, and non-infectious agents are associated with diarrhoea, about 40% of diarrhoeal cases are considered to be of unknown etiology (Denno et al, 2007;Greniger et al, 2009;Holtz et al, 2008;Holtz et al, 2009).…”

“…Hence majority of the epidemiological studies on diarrhoea failed to include NPEVs in their investigations. Further, the causative agents in about 30-40% of diarrheal cases are yet to be identified (Denno et al, 2007;Greniger et al, 2009;Holtz et al, 2008;Holtz et al, 2009).…”

Comparative analysis of six genome sequences of three novel picornaviruses, turdiviruses 1, 2 and 3, in dead wild birds, and proposal of two novel genera, Orthoturdivirus and Paraturdivirus, in the family Picornaviridae

“…1a). These novel picornaviruses seemed to be most closely related to Aichi virus and bovine kobuvirus of the genus Kobuvirus, as well as porcine kobuvirus and klassevirus, which were proposed to be members of the genus Kobuvirus, and salivirus, which was at the borderline between a new genus and a highly divergent species in the genus Kobuvirus (Holtz et al, 2009;Li et al, 2009;Reuter et al, 2009). Since these three clusters of novel picornaviruses were all found in birds of the genus Turdus in the family Turdidae, or Copsychus saularis (oriental magpie robin), which was previously also classified in the family Turdidae (del Hoyo et al, 2005), we propose the three viruses to be named turdiviruses 1, 2 and 3 (TV1, TV2 and TV3, respectively).…”

“…Genome sequencing and comparative analysis showed that the three viruses fell into two distinct clusters. They were most closely related to, but distinct from, members of the genus Kobuvirus in the family Picornaviridae (Holtz et al, 2009;Li et al, 2009;Reuter et al, 2009;Yamashita et al, 1998Yamashita et al, , 2003. Based on our results, we propose two novel genera, Orthoturdivirus and Paraturdivirus, in the family Picornaviridae.…”