Newly Discovered Virus Replicates in a Completely Unknown Way

A review of:

Saplakoglu, Yasemin. “This Newly Discovered Virus Replicates in a Completely Unknown Way.” LiveScience, Purch, 28 Oct. 2019, www.livescience.com/new-virus-discovered-lacking-important-proteins.html.

I chose to review the article “This Newly Discovered Virus Replicates in a Completely Unknown Way” by Yasemin Saplakoglu. This was a relatively short article which shared information about a newly discovered type of enterovirus G (EV-G). This new virus was the result of two other viruses that shared genetic material, an enterovirus G and a torovirus. What is so surprising about this new virus, is that is is able to thrive, even though it lacks the proteins necessary for replication. Enteroviruses are spread through infected organisms as well surfaces covered with the virus, and are transmittable through fecal matter, saliva, mucus and other bodily liquids. Researchers in Japan studying pig and cow poop discovered the virus, as “these dirty environments, where lots of animals constantly interact, are a good place for viruses to quickly evolve”(Yasemin). The new EV-G strain, named type 2 EV-G, lacks an important feature that is present in all other known viruses. It lacks “structural proteins,” as they are called, which allow microbes to attach to, enter, and replicate within host cells. The virus strain does not have the genes which code for these proteins, though the virus does contain “unknown” and not previously studied genes. “Without structural proteins, the virus shouldn't be able to infect other cells,” says Tetsuya Mizutani, the director at the Research and Education Center for Prevention of Global Infectious Disease of Animal (TUAT) in Japan. Despite this, the same virus was found on the same farm within the fecal matter of pigs over three years later, suggesting that the virus is somehow thriving and replicating within pigs. The researchers hypothesized that the type 2 EV-G virus borrowed structural proteins from other nearby viruses referred to as “helper viruses,” similar to how hepatitis D relies on hepatitis B for replication despite having its own structural proteins.

This discovery has implications for human society and possible developments in preventing and treating the viruses that plague humans. While the various strains of EV-G cannot currently infect humans, there is a distinct possibility that viruses that do have the ability to infect humans may evolve in a similar fashion. "Understanding how viral recombination occurs and how viruses develop dependencies on helper viruses is an important key to unlocking some of the mysteries of virus evolution," says Amesh Adalja, an infectious disease specialist. In 2013, the International Committee on Taxonomy of Viruses (ICTV) approved changes to EV and rhinovirus species names, and a later proposal was made to drop the designation of viruses as human, bovine, porcine, and simian^1 after studying the genetic similarity of the viruses and human enterovirus species were successfully isolated in non-human hosts. There is a high chance that many EVs that naturally exist and circulate through animal populations may also be infecting humans. For this reason, the study of viruses and viral evolution is key for keeping human populations protected, particularly the more susceptible infant population and children under the age of one. The study of these viruses and the environmental causes of their evolution serve as a reminder of the importance of maintaining hygienic conditions in areas with high human populations.

Yasemin’s article smartly condensed information and presented it in a way that would be easy to understand for anyone. The article introduced the discovery of the new enterovirus, and gave background information on who and how the discovery was made. The article also highlighted how this discovery prompted more research and the questions that it raised - and the desire of Mizutani and his team “to figure out which helper viruses enable 2 EV-G to survive, and exactly what the unknown genes do”(Yasemin). However, I found that the article was a bit lacking in information, and I had to do some outside research to answer some of the questions I developed while reading the article. I was glad to find that the author included a link to the original publication of this discovery. I think the article would have been much more credible and beneficial if it also contained additional references, citations, or links to other,related research.

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1.  Fieldhouse, Jane K, et al. “A Systematic Review of Evidence That Enteroviruses May Be Zoonotic.” National Center for Biotechnology Information , Nature Publishing Group UK, 26 Sept. 2018, www.ncbi.nlm.nih.gov/pmc/articles/PMC6158190/.