Epidemiology and Clinical Associations of Human Parechovirus Respiratory Infections

Abstract

Infections with human parechoviruses (HPeVs) are prevalent in young children and have been associated with mild gastroenteritis and, less frequently, with meningitis and neonatal sepsis. To investigate the involvement of these viruses in respiratory disease, a highly sensitive nested PCR was used to screen a large archive of respiratory specimens, collected between January and December 2007. Respiratory samples had previously been tested for eight respiratory viruses, including respiratory syncytial virus and adenovirus, by PCR. HPeV was detected in 34 of 3,844 specimens, representing 27 of 2,220 study subjects (1.2%). HPeV types were identified by sequencing the VP3/VP1 junction amplified by PCR directly from clinical specimens. The assay could amplify all HPeV types examined with high sensitivity (types 1 and 3 to 6) and also identified HPeV types in all but one of the screen-positive study specimens (25 HPeV1 and eight HPeV6 specimens). Infections with both HPeV1 and HPeV6 were seasonal, with highest frequencies in July and August, and restricted to children aged between 6 months and 5 years. Other respiratory viruses were frequently codetected in HPeV-positive specimens, with significant overrepresentation of adenovirus coinfections (37%). Most HPeV-positive specimens were referred from emergency departments, although no association with specific respiratory symptoms or disease was found. In summary, the low frequency of detection and lack of clear disease associations indicate that HPeV1 and -6 are not major pathogens in individuals presenting with respiratory disease. However, the screening and typing methods developed will be of value in further HPeV testing, including testing for meningitis cases and other suspected HPeV-associated disease presentations.

Evolution and conservation in human parechovirus genomes

“…Several diagnostic laboratories now screen for HPeV infection and together with the retrospective analysis of archived material, a growing number of HPeV associations with disease have been reported recently (Baumgarte et al, 2008;Benschop et al, 2006aBenschop et al, , 2008bBoivin et al, 2005;De Souza Luna et al, 2008;De Vries et al, 2007;Drexler et al, 2009;Harvala et al, 2008Harvala et al, , 2009Li et al, 2009;Tauriainen et al, 2008;Wakatsuki et al, 2008;Wolthers et al, 2008). A greater understanding of the biology and molecular biology of these viruses is therefore required.…”

“…Currently, parechoviruses consist of two species: human parechovirus (HPeV) and Ljungan virus (LV) (Johansson et al, 2002;Joki-Korpela & Hyypiä, 2001;Stanway & Hyypiä, 1999;Stanway et al, 2000). HPeVs are frequent infectious agents and although they usually cause mild gastroenteritis and respiratory disease in young children, more serious cases, such as flaccid paralysis, encephalitis and myocarditis, have also been reported, particularly associated with HPeV3 infection (Baumgarte et al, 2008;Benschop et al, 2006a Benschop et al, , 2008bEhrnst & Eriksson, 1993;Figueroa et al, 1989;Harvala et al, 2008Harvala et al, , 2009Joki-Korpela & Hyypiä, 2001). Recently, HPeV1 has also been linked to otitis media (Tauriainen et al, 2008).…”

Human Parechoviruses, New Players in the Pathogenesis of Viral Meningitis

“…Similar data were found in studies on stool samples in other European countries (Baumgarte et al, 2008;Tapia et al, 2008), and Asia (Ito et al, 2010;Pham et al, 2010Pham et al, , 2011aWatanabe et al, 2007) where HPeV1 was identified as the most prevalent type, followed by HPeV3. HPeV4 is frequently found in stools as well (Benschop et al, 2008c(Benschop et al, , 2010aBoros et al, 2010;Pham et al, 2011b;Zhong et al, 2011), while HPeV6 seems to prevail as a secondary respiratory pathogen (Harvala et al, 2008). Infections with HPeV2 and 5 are reported sporadically (Benschop et al, 2010a;Ehrnst & Eriksson, 1996;van der Sanden et al, 2008).…”

“…The same is described for HPeV4 and 6 (Benschop et al, 2008c(Benschop et al, , 2010aHarvala et al, 2008;Pajkrt et al, 2009). Again, not only in clinical sense, but also from a epidemiological point of view, HPeV3 behaves different from other HPeV types.…”

“…HPeV1 is considered as the predominant strain mainly affecting young children (Baumgarte et al, 2008;Benschop et al, 2006aBenschop et al, , 2008cBenschop et al, , 2010aHarvala et al, 2008;Joki-Korpela & Hyypia, 1998;Stanway et al, 2000;Tapia et al, 2008;Watanabe et al, 2007). Epidemiological studies dating back over 30 year ago, showed HPeV1 to be widely spread (Ehrnst & Eriksson, 1993;Grist et al, 1978;Joki-Korpela & Hyypia, 1998;Khetsuriani et al, 2006b).…”