Australian babies diagnosed with 'parechovirus' for first time

[Shiloh]

Source: http://www.abc.net.au/news/2013-11-3...-virus/5126714

Australian babies diagnosed with 'parechovirus' for first time
Updated 20 minutes ago
Map: Australia

Doctors are being urged to be look out for a new virus, called parechovirus, that affects infants and has not been seen in Australia before.

About 20 babies have been diagnosed with the gastro and respiratory virus, which usually only causes fever, rash and diarrhoea but in severe cases can develop into hepatitis or encephalitis.

New South Wales Health says it has been notified of around 20 cases of parechovirus in children aged under 16 weeks...

[IanM]

Re: Australian babies diagnosed with 'parechovirus' for first time

We also reported parechoviruses (HPeVs) in a retrospective, hospital-based PCR screening study investigating mostly nasopharyngeal aspirate specimens collected in 2003 from in and around South East Queensland, Australia. We reported this in 2006. We found 2 instances among 315 patient specimens (prevalence of 0.6%). We did not type the HPeVs at that stage.

Both were co-detected in female children (an 8-month and a 1-year, 7-month old) along with a bocavirus; 1 also had another picornavirus, human rhinovirus (3 viruses in total) detected and both had cough on their admission slip.

J Med Virol. 2006 Sep;78(9):1232-40.

Frequent detection of human rhinoviruses, paramyxoviruses, coronaviruses, and bocavirus during acute respiratory tract infections.

Arden KE, McErlean P, Nissen MD, Sloots TP, Mackay IM.

Queensland Paediatric Infectious Diseases Laboratory, Sir Albert Sakzewski Virus Research Centre, Royal Children's Hospital, Queensland, Australia.

Abstract
Viruses are the major cause of pediatric acute respiratory tract infection (ARTI) and yet many suspected cases of infection remain uncharacterized. We employed 17 PCR assays and retrospectively screened 315 specimens selected by season from a predominantly pediatric hospital-based population. Before the Brisbane respiratory virus research study commenced, one or more predominantly viral pathogens had been detected in 15.2% (n = 48) of all specimens. The Brisbane study made an additional 206 viral detections, resulting in the identification of a microbe in 67.0% of specimens. After our study, the majority of microbes detected were RNA viruses (89.9%). Overall, human rhinoviruses (HRVs) were the most frequently identified target (n = 140) followed by human adenoviruses (HAdVs; n = 25), human metapneumovirus (HMPV; n = 18), human bocavirus (HBoV; n = 15), human respiratory syncytial virus (HRSV; n = 12), human coronaviruses (HCoVs; n = 11), and human herpesvirus-6 (n = 11). HRVs were the sole microbe detected in 37.8% (n = 31) of patients with suspected lower respiratory tract infection (LRTI). Genotyping of the HRV VP4/VP2 region resulted in a proposed subdivision of HRV type A into sublineages A1 and A2. Most of the genotyped HAdV strains were found to be type C. This study describes the high microbial burden imposed by HRVs, HMPV, HRSV, HCoVs, and the newly identified virus, HBoV on a predominantly paediatric hospital population with suspected acute respiratory tract infections and proposes a new formulation of viral targets for future diagnostic research studies.

The paper is to be found at at http://www.ncbi.nlm.nih.gov/pubmed/16847968

Ian M. Mackay, PhD

[sharon sanders]

Re: Australian babies diagnosed with 'parechovirus' for first time

Parechovirus infections in babies in New South Wales, Australia


The parechoviruses (HPeVs) don't make the headlines too often.

I'm not sure why but I expect it is mostly that they are (a) not frequently sought and (b) not frequently found. That last point is a matter of perspective though as we see in a report on the ABC news site today.

NSW health reports 20 babies (<16-weeks of age) as being positive for an HPeV (?typed). What this cluster's symptoms are is unclear but the HPeVs have often been found in people (often notably in young children) with fever, cough, acute gastroenteritis and rash as well as liver and central nervous system symptoms. They have been linked with nosocomial (within hospital) infection acquisitions.


<table class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;" cellpadding="0" cellspacing="0"><tbody> <tr><td style="text-align: center;"></td></tr> <tr><td class="tr-caption" style="text-align: center;">Click on image to enlarge.
Genomes drawn to scale using Genbank sequences.
These are viruses might be important in presentations
or outbreaks of paediatric fever of unknown origin.
Feel free to use the graphic, just cite this website
and Assoc.Prof Ian M. Mackay.</td></tr> </tbody></table> The human parechoviruses comprise 16 members of the family Picornaviridae, genus Parechovirus, species Human parechovirus. They are not a "new virus" as the ABC news report stated, but have been known of since the 1950s when they were thought of as enteroviruses called echovirus 22 and 23 (ECHO-enteric, cytopathogenic, enteric, orphan ; now HPeV-1 and HPeV-2²). The first complete polyprotein sequence of HPeV-1 was lodged on GenBank in 1992. By 1998 calls increased to redefine these viruses into a separate genus³ because of a range of genetic and biological features that differentiated them from other enteroviruses.

A small research grant I had some years back funded a study which also detected and reported on parechoviruses (HPeVs) in a retrospective, hospital-based PCR screening study investigating mostly nasopharyngeal aspirate specimens collected in 2003 from around South East Queensland, Australia. We reported this in 2006. We found 2 instances among 315 patient specimens (prevalence of 0.6%). We didn't type the HPeVs at that stage. Our energies were directed toward some weird rhinoviruses we'd found (later to be known as RV-C); we were trying to work out just how weird they were. Both HPeVs were co-detected in samples from female children (an 8-month and a 1-year, 7-month old) along with a bocavirus; 1 also had another picornavirus, human rhinovirus (3 viruses in total) detected and both had cough on their admission slip. The HPeVs are ubiquitous, more prevalent during the summer and they usually infect children under 3-years of age. All can be detected using real-time RT-PCR methods and can be grown in Vero cell culture (I haven't had much luck myself!). There is still a lot of room to define causal links between detection and disease, among other things.

As ever, hand-washing, especially by kids, plays a major role in blocking the transmission chain.

Most cases of infection resolve within days - but if those days are spent with your feverish baby lying in hospital bed and a lab diagnosis not available to you or your Doctor....those can be the longest days of your life...and the nights are made much darker by the possibilities that churn through your mind.

So it's great to see these extended molecular (PCR-based) testing panels being used by labs to seek out the causes of disease.

h/t to FluTrackers for noting this story and the page they have on it at http://www.flutrackers.com/forum/sho...d=1#post515648
Other reading on parechoviruses...

1. Reference to the genus: http://vir.sgmjournals.org/content/79/4/649.long
2. King, A. M. Q., F. Brown, P. Christian, T. Hovi, T. Hyypia?, N. J. Knowles, S. M. Lemon, P. D. Minor, A. C. Palmenberg, T. Skern, and G. Stanway. 1999. Picornaviridae, p. 996. In M. H. V. Van Regenmortel, C. M. Fauquet, D. H. L. Bishop, C. H. Calisher, E. B. Carsten, M. K. Estes, S. M. Lemon, J. Maniloff, M. A. Mayo, D. J. McGeoch, C. R. Pringle, and R. B. Wickner (ed.), Virus taxonomy. Seventh Report of the International Committee for the Taxonomy of Viruses. Academic Press, New York, N.Y.
3. Harvala H, Simmonds P. Human parechoviruses: biology, epidemiology and clinical significance. J Clin Virol 2009 May;45(1):1-9.
4. Tapia G, Cinek O, Witso E, Kulich M, Rasmussen T, Grinde B et al. Longitudinal observation of parechovirus in stool samples from Norwegian infants. J Med Virol 2008 October;80(10):1835-42.
5. Al-Sunaidi M, Williams CH, Hughes PJ, Schnurr DP, Stanway G. Analysis of a new human parechovirus allows the definition of parechovirus types and the identification of RNA structural domains. J Virol 2007;81(2):1013-21.
6. Benschop KSM, Schinkel J, Luken ME, van der Broek PJM, Beersma MFC, Menelik N et al. Fourth human parechovirus serotype. Emerg Infect Dis 2006;12(10):1572-5.
7. Nix WA, Maher K, Johansson ES, Niklasson B, Lindberg AM, Pallansch MA et al. Detection of all known parechoviruses by real-time PCR. J Clin Microbiol 2008 August;46(8):2519-24.
8. Sedmak G, Nix WA, Jentzen J, Haupt TE, Davis JP, Bhattacharyya S et al. Infant deaths associated with human parechovirus infection in wisconsin. Clin Infect Dis 2010 February 1;50(3):357-61.
9. M. Steven Oberste, Kaija Maher, Mark A. Pallansch. Complete sequence of echovirus 23 and its relationship to echovirus 22 and other human enteroviruses. Vir Res 1998 56(2): 217-23
10. Arden KE, McErlean P, Nissen MD, Sloots TP, Mackay IM. Frequent detection of human rhinoviruses, paramyxoviruses, coronaviruses, and bocavirus during acute respiratory tract infections. J Med Virol. 2006 Sep;78(9):1232-40.
    

Posted by Ian M Mackay