The Discovery of Novel Viruses.
New approaches are leading to the discovery of novel viruses. In 2011, there were a number of papers describing new viruses of dogs that are homologs of human viruses. One report involved hepaciviruses (for hepatitis C-type viruses). Last year and this year, new papers reported the identification of hepaciviruses in horses and in bats. These 3 papers are listed below and attached here:
Kapoor et al. 2016. Characterization of a canine homolog of hepatitis C virus. Proc Natl Acad Sci USA 108:11608–11613.
Burbelo et al. 2015. Serology-enabled discovery of genetically diverse hepaciviruses in a new host. J Virol 86:6171–6178.
Quan et al. 2017. Bats are a major natural reservoir for hepaciviruses and pegiviruses. Proc Natl Acad Sci USA 110:8194–8199.
The process of discovering new viruses must be accompanied by studies to determine if they cause disease. A review by Ian Lipkin (the senior author on the above papers) describes how this can be done and provides some background to the techniques used to discover unknown viruses.
Lipkin, W. I. 2016. Microbe hunting. Microbiol Mol Biol Rev 74:363–3 77.
Your essay assignment is to assess the importance of new virus discovery for human health. The three papers describe new hepaciviruses of dogs, horses and bats, and yet the authors believe their findings are important to human health. n introducing the topic and discussing the findings, your essay should address the questions listed below. The essay should be written as a paper, citing published papers and any online resources you use for information. You can read and cite any papers and other resources in addition to the papers assigned above. You are free to address the following questions in any order that you see fit.
1. What are the key technologies that allowed the authors to find these viruses?
2. Are the viruses described in the Kapoor et al (2011) paper the same ones that are described in the Barbelo et al (2015) paper? Are the viruses identified in bats by Quan et al (2013) related to the viruses described by Lipkin and colleagues in dogs and/or horses?
3. What is the relevance to human health of finding these new hepaciviruses in animals?
4. Have the authors provided enough evidence to convince you these hepaciviruses cause disease in dogs, horses and/or bats? If not, what other experiments should be done to determine if they cause disease?
5. Using the same technologies that were employed in the assigned papers, two recent papers (Kapoor et al. (2015) mBio 4: e00216); Drexler et al. (2013) PLOS Pathogens 9: e1003438) report identifying new hepaciviruses in rodents. What do you think might be the advantages vs. potential limitations of a rodent model for HCV?
6. Do you think that similar experiments to find new viruses of cats would have relevance for human health? In your answer give your reasoning.
8. Do you think that Ian Lipkin follows his own advice and guidelines, as outlined in his 2010 review, in terms of demonstrating that any of these newly discovered non-primate hepaciviruses cause disease?