Robin MacDiarmid | January 27, 2021 from GlobalHQ on Vimeo.
A single slice from any flora or fauna sample analysed in a lab may contain hundreds if not thousands of viruses and bacteria, but the number actually known, categorised and understood by scientists may well pale against the total there.
For Dr Robin MacDiarmid, identifying and categorising the viruses represents barely half the job at hand. In recent decades genomic sequencing has made that task simpler, quicker and more affordable for researchers.
“But once you have discovered and categorised a virus, you are really only at the ‘so what?’ stage. The big questions come after that, in terms of what is its cell biology, and what is the ecosystem it functions in?” MacDiarmid said.
“Typically, and particularly in 2020, people tend to think if something is a virus, then it must be bad, that’s the reputation they have.”
She compares this to their microscopic bedmates bacteria, where people are familiar not only with their negative impact, such as causing infection, but equally comfortable with their positive side. This includes creating fermented foods and in the human microbiome that assists us in nutrition and disease control.
So, MacDiarmid welcomes the timely discussions around the use of tools like attenuated viral vaccines in the war against covid if it helps increase knowledge and understanding of those potential positives.
Attenuated vaccines are created by reducing the strength of a viral pathogen, but keeping it viable or live. This stimulates a strong immune response from the host that tends to be long-lasting.
Attenuated vaccines, such as those being developed at the University of Melbourne, are one of six categories of vaccine being worked on for covid defences
The use of a virus as “mild strain cross-protection,” is a type of vaccination used to inoculate plants against viral diseases which can otherwise be hard to deal with. An example is potato viruses which can require treatment of soils with to eradicate them
While known for over 100 years, the past decade has seen a rise in interest in inoculants’ use as researchers seek alternative non-synthetic crop treatments. Such treatments have proven effective in trials on apple and tomato mosaic viruses.
Life and crop-saving vaccines aside, the positives viruses’ invisible presence may bring can be difficult for researchers to prove.
“We have been carrying on life not thinking about viruses, but have probably been propagating them,” she said.
“Many of our crops today are not raised from seed, but propagated through vegetative techniques like grafting, cuttings and tissue culture. This means any viruses from the original mother plant remain, and are passed on through those generations for many decades. What we have not done is ask ‘what are the viruses found in these plants conferring, possibly in a positive way?’”
It is a difficult question to answer, requiring researchers to tip the conventional research approaches on its head – that is one usually requiring them to look at unhealthy samples to find out why they are in malaise.
“It’s a steep research path, having to test for what the factors are that cause that virus to be present in a positive, healthy host, quite a contrast to identifying and treating harmful viruses,” she said.
New Zealand presents more challenge and opportunity in this area, given when the country was settled, edible plants were difficult to prepare.
“We have this very unique flora and fauna in NZ that has had exotic crops, pathogens and pests introduced to it. But there has been very little research on the impact of exotic viruses on our indigenous plants, or vice versa for that matter,” she said.
MacDiarmid sees plenty of opportunity over the next five years to examine viruses that may play a positive role in replacing synthetic sprays and offer a more socially acceptable means of protection.
There is also the potential for viruses to be used to attack the pathogenic bacteria that impact on our crops. Known as phages, work is going on here too, and could hold potential to deal with problematic bacterial diseases in a wide range of horticultural crops.
“We are hoping the concept of good viruses is one that becomes acceptable to growers and consumers. This is a great area of research – there is a mix here of science, philosophy, social and economic research,” she said.
