Researchers say there is no need for alarm after 83 endemic novel viruses were recently discovered in New Zealand.
Viruses are known to cause disease outbreaks or pandemics such as Covid-19, but the vast majority just seem to infect hosts without causing overt signs of disease.
Dr Rebecca Grimwood was inspired to study New Zealand’s virosphere as part of her PhD in genetics at the University of Otago because the country’s isolation from the rest of the world meant it was possible there were undiscovered viruses that were unique to New Zealand and its indigenous species.
Her research looked at the virome (the collection of all viruses found in an organism) of 24 hosts, including some native species of birds and fish.
As a result, she discovered 83 endemic novel viruses, which has produced previously unknown data on the natural environment, for New Zealand’s farming and fishing practices.
One of her studies was in collaboration with the Ministry for Primary Industries about a disease causing diarrhoea and oral lesions in the mouths of calves on a cattle farm.
She was able to identify some of the viruses that may be causing the disease.
She also found a virus that was potentially causing tail fan necrosis in spiny red rock lobsters, but said more research needed to be done to confirm it.
The shell disease affects its health and economic viability.
She said her study demonstrated how important it was to integrate genomics into wildlife surveillance and disease investigations, particularly in understudied animals, birds and fish.
“Genomic sequencing tools are giving us new opportunities to understand what’s around us — in particular, pathogens that pose a threat to agriculture and wildlife.”
Her PhD supervisor, University of Otago microbiologist and immunologist Prof Jemma Geoghegan, said viruses were all over the planet, but were often overlooked essential players in the formation, turnover and maintenance of life on Earth.
“We want to understand what changes in the virus or the host or the environment that then can lead to disease outbreaks.
“So what makes a virus become more severe to cause disease?”
It usually happened when the virus jumped to a new host species, she said.
“So it’s happily hanging out in one host species and then it merges into another one that might be a human or it might be a different animal and then sometimes that causes disease.
“So we wanted to better understand that process. But to do that, we needed to understand what is out there in the first place as well.
“The aim of the study was to understand the true diversity of viruses that exist in New Zealand.
“We did find lots of very interesting viruses here that really expand our knowledge of virus diversity and understanding of what viruses make up the normal ecosystem without necessarily causing disease.”
However, on a global scale, she said scientists had only scratched the surface of identifying viruses and knowing their purpose.
“In fact, science has probably only discovered 1% of what’s out there.”