320,000 new viruses could be harbored by mammal hosts from all over the world, a new study suggests. The alarming figure was extrapolated from the 60 unknown pathogens recently identified in the flying fox, a tropical bat species. Although it would cost billions of dollars to establish a comprehensive blueprint of these foreign viral strains, researchers argue that the expenses would only amount to a fraction of those attending a pandemic.
According to Professor Ian Lipkin, director of the Center for Infection and Immunity at Columbia University’s Mailman School of Public Health, the exhaustive project will allow scientists to grasp the extent of our world’s pathogenic fauna. A firm understanding of viral and bacterial diversity will permit more accurate epidemiological predictions as well as more solid containment strategies. That said, the project would require about $6 billion in funding and a decade of research.
"What we're really talking about is defining the full range of diversity of viruses within mammals, and our intent is that as we get more information we will be able to understand the principles that underlie determinants of risks," Lipkin said, speaking to BBC. "Despite what looks like an extraordinary expense to pursue this kind of work, it really pales in comparison with what one might learn that could lead to very rapid recognition and intervention that could come to the fore with a pandemic risk.”
While almost 70% percent of all viruses that affect humans originate in wildlife, the extent of the problem has long been difficult to assess, and few rigorous estimates have been attempted. The new study investigated the issue by focusing on a single species – the flying fox bat. Extrapolating statistical data from 1,897 samples, they were able to derive a preliminary universal figure: 320,000.
"Obviously we cannot survey every animal on the planet, but we can try and map as best as we can using a concept referred to as hotspots,” Lipkin explained. "We look at areas where we know, based on previous experience, there is a high likelihood that new infectious agents will emerge or will pose considerable threat to human health."
Rather than a final assessment, the research effort is intended as a template for future inquiry. The strategy detailed in the paper will allow other groups to augment and reformulate the current estimates by identifying more viral agents in other mammals. This way, the project may approach its goal gradually, without massive, direct funding.
Source: Anthony SJ, Epstein JH, Murray KA, Navarrete-Macias I, Zambrana-Torrelio CM, Solovyov A, Ojeda-Flores R, Arrigo NC, Islam A, Ali Khan S, Hosseini P, Bogich TL, Olival KJ, Sanchez-Leon MD, Karesh WB, Goldstein T, Luby SP, Morse SS, Mazet JAK, Daszak P, Lipkin WI. 2013. A strategy to estimate unknown viral diversity in mammals. mBio 4(5):e00598-13. doi:10.1128/mBio.00598-13.