An outbreak of severe infections among Australian infants caused by a novel recombinant strain of human parechovirus type 3

Abstract

Human parechovirus types 1–16 (HPeV1–16) are positive strand RNA viruses in the family Picornaviridae. We investigated a 2015 outbreak of HPeV3 causing illness in infants in Victoria, Australia. Virus genome was extracted from clinical material and isolates and sequenced using a combination of next generation and Sanger sequencing. The HPeV3 outbreak genome was 98.7% similar to the HPeV3 Yamagata 2011 lineage for the region encoding the structural proteins up to nucleotide position 3115, but downstream of that the genome varied from known HPeV sequences with a similarity of 85% or less. Analysis indicated that recombination had occurred, may have involved multiple types of HPeV and that the recombination event/s occurred between March 2012 and November 2013. However the origin of the genome downstream of the recombination site is unknown. Overall, the capsid of this virus is highly conserved, but recombination provided a different non-structural protein coding region that may convey an evolutionary advantage. The indication that the capsid encoding region is highly conserved at the amino acid level may be helpful in directing energy towards the development of a preventive vaccine for expecting mothers or antibody treatment of young infants with severe disease.

Evolutionary and network analysis of virus sequences from infants infected with an Australian recombinant strain of human parechovirus type 3

“…1 to design a custom Ion AmpliSeq Panel (here referred to as panel 1) for use with Ion Torrent S5 System (Thermo Fisher Scientific, Vic. Australia).…”

Parechovirus: an important emerging infection in young infants

“…However, in contrast to other countries, epidemics in Australia have been larger and associated with more severe disease (and poorer clinical outcomes) 14 , 15 . Recently, whole genome sequencing has shown that the first Australian epidemic was likely caused by a novel recombinant HPeV3 16 …”

Strain-dependent neutralization reveals antigenic variation of human parechovirus 3

“…While most HPeVs cause mild disease in children between 1 to 5 years of age, HPeV3 infection more often leads to severe illness in infants under 3 months of age 3 – 5 . HPeV3 is prevalent worldwide and outbreaks have been reported in the Netherlands, Japan and Australia 1 , 6 – 11 . Despite the large clinical impact of these viruses, no vaccines or targeted antiviral therapies are available against HPeVs.…”