The Invisible World of Viruses
Viruses are the most common organisms on our planet. They’re also invisible to the human eye — and largely ignored. Out of sight equals out of mind for most people. But just because they can be seen doesn’t mean they’re not out there. Check the papers and there’s always a story about some virus. Influenza, Zika. Ebola. Virus outbreaks, big and small, are happening all the time.
Viruses also cost society a lot of money. The World Bank recently estimated that the cost of Zika alone will be about $3.5 billion in Latin America and the Caribbean in 2016, a sum they considered “modest”. Other countries could see much economic impact, they warned. Meanwhile, the annual cost of the flu in the US has been estimated at $87 billion, and colds, less serious, at about $40 billion. HIV research and treatment costs the US another $25 billion. There’s no reliable figure for the annual global economic cost of viruses, let alone the cost of human suffering.
But for all the money we’ve spent and continue spending on viruses, we still know relatively little about them. As of March 2016, only 5511 complete virus genomes have been published, despite their small genome size. We don’t have any idea of the total number of virus species. Millions? Billions? What even distinguishes one virus species from another? There are currently no rapid diagnostic kits available to doctors for identifying any viruses outside of a very select few. Worse, aside from flu and HIV, there are few antivirus treatments. When the first Ebola case was diagnosed in the US in 2014, it sent shudders through the healthcare system. Not only were vaccines or treatments not readily available, but few hospitals or staff were prepared to deal with patients with Ebola.
Viruses are truly the dark matter of biology. Too small to be seen with light microscopes, they’ve been invisible and unexplored for too long. But there is change on the horizon. The appearance of low-cost DNA sequencing is proving to be a game-changer. It’s now easier than ever to sequence a virus genome. This code can generate an incredibly detailed profile of a virus, even if the physical form of agent cannot be directly imaged. Because of sequencing, viral discovery and analysis has been accelerating. Soon, just as the human microbiome has been mapped, and personal microbiome information is revealing surprising and actionable data, the human virome — the catalog of all viral species that commonly affect humans — may soon be complete.
What will this catalog mean for medicine? In the short term, it’s hard to say. But faster, cheaper, and more comprehensive detection of the viruses in and around us can only be a good thing. Collecting this information is long overdue — we’ve got to close this gap in our understanding of the world around us. It could immediately benefit disease research given there’s growing evidence that viruses are involved in Multiple Sclerosis (MS) and perhaps even Alzheimer’s. Better information gathering — for example, automatic contact tracing from cell phone location data — combined with cheap screening tests could also make public health more efficient and cost-effective. And the use of fast, inexpensive nanopore sequencers could revolutionize point-of-care diagnosis and treatment of acute viral diseases like meningitis.
The human virome could shift public perception about viruses. Since their discovery in the late 1800’s, viruses have mostly been associated with human disease and disease outbreaks. There’s almost an automatic fear of them. But the vast majority of viruses are completely harmless to humans. Chances are good that viruses have many positive roles in ecosystems, and that are a major force in the evolution of new species. In fact, between 5 and 8 percent of our genome is viral in origin.
“[virus’] primary role is essentially to be a biological flash drive. This makes them amenable to engineering, which looks a lot like software engineering.”
A better view into the world of viruses should lead to a more nuanced view of their roles in nature. This view could even help us domesticate these remarkable agents. Their primary role is essentially to be a biological flash drive. This makes them amenable to engineering, which looks a lot like software engineering. Over the decades, viruses have played an essential role in biological R&D, helping scientists understand molecular mechanisms, and developers create everything from new vaccines, to gene therapies and cancer treatments.
More recently, DNA synthesis technologies have improved to the point where the complete synthesis of any viral genome is within technical reach. With further advances in design software and robotic manufacturing systems, near real-time prototyping of these powerful agents will be achievable. When it is, we may find that rather than cause human disease, viruses could usher in an age of truly personalized medicines.
Andrew Hessel is a Distinguished Research Scientist at Autodesk