Human Parechovirus Type 3 (HPeV3): The cause of severe emerging infection in young children

What is Parechovirus?

Parechovirus is similar to the better known enteroviruses – viruses that cause common infectious diseases such as hand, foot and mouth diseases in children. According to research published in the Medical Journal of Australia, epidemics of human parechovirus (HPeV) causing severe disease in young children have occurred every 2 years in Australia since 2013.

There are 17 genotypes of parechovirus, three of which – 1, 3 and 6 – are associated with disease in humans. Genotype 3 (HPeV3) has now been identified as the strain that has been associated with causing serious illnesses specifically central nervous system infection and a sepsis-like syndrome in children less than 3 months of age. Additionally, neurological problems and developmental delay have also been observed in up to 50% of children in the 12-18 months after an HPeV3 infection requiring hospitalization.

Collaborative Research

The project that unlocked the genetic code of the parechovirus was funded by the National Health and Medical Research Council (NHMRC) of Australia and led by infectious disease specialists nationwide – including senior author, Professor Soren Alexandersen, Director of the Geelong Centre for Emerging Infectious Diseases (GCEID, a partnership between Barwon Health, CSIRO and Deakin University) and APPRISE researcher and Professor Kristine Macartney, Director of the National Centre for Immunisation Research and Surveillance (NCIRS) and leader of the Paediatric Active Enhanced Disease Surveillance (PAEDS) network.

PAEDS have been tracking the frequency of HPeV cases since August 2017, and recorded over 200 cases of infants hospitalised in 2017-2018, which is the largest HPeV epidemic to date.

“Although this more severe strain of parechovirus has not been reported anywhere else in the world, the genetic changes suggest the virus is also circulating and evolving outside of Australia in between our outbreaks,” Professor Alexandersen said.

Co-author of the study - Dr Philip Britton, Paediatric Infectious Diseases Physician, researcher at The Children’s Hospital at Westmead and senior lecturer of Child and Adolescent Health at The University of Sydney said the study not only managed to genetically characterize the human parechoviruses involved in the outbreak in 2017-2018 but also enabled researchers to design a single database for harmonised collection of information, in preparation for any future outbreaks.

“We can’t predict the future, but if we were to have another epidemic over the 2019–2020 season, our ability to undertake real-time data collection will allow us to compare the features of a future epidemic with past epidemics to better understand the evolution of this virus that is of clinical and public health significance to Australia.”

“The databases will also allow researchers to better answer important public health questions such as how does the parechovirus spread through communities and what are the major locations and risk factors for transmission.”

Please refer to the full article here, you can also listen to Dr Philip Britton discuss the emerging epidemic in detail in this podcast with the Medical Journal of Australia.