Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UT professor uncovers clues into how viruses jump from hosts

06.08.2010
Researcher finds that cross-species transmission may have less to do with virus mutation and contact rates and more to do with host similarity

HIV-AIDS. SARS. Ebola. Bird Flu. Swine Flu. Rabies. These are emerging infectious diseases where the viruses have jumped from one animal species into another and now infect humans. This is a phenomenon known as cross-species transmission (CST) and scientists are working to determine what drives it. Gary McCracken, a professor at the University of Tennessee, Knoxville, and department head in Ecology and Evolutionary Biology, is one of those scientists and has made a groundbreaking discovery into how viruses jump from host to host.

His article, "Host Phylogeny Constrains Cross-Species Emergence and Establishments of Rabies Virus in Bats," will appear in the Aug. 6 edition of Science and will be featured on the issue's cover.

It has been a long-held belief that rapid mutation is the main factor that allows viruses to overcome host-specific barriers in cellular, molecular or immunological defenses. Therefore, it has been argued that viruses emerge primarily between species with high contact rates.

McCracken and his colleagues now report that CST may have less to do with virus mutation and contact rates and more to do with host similarity.

"That innate similarity in the defenses of closely related species may favor virus exchange by making it easier for natural selection to favor a virus' ability to infect new hosts," McCracken explained.

McCracken performed his research with former UT Knoxville Ph.D. student Amy Turmelle who now works with the Centers for Disease Control (CDC) and Maarten J. Vonhof, a former post-doctoral scholar at UT Knoxville, who is now with Western Michigan University. Other colleagues include CDC Rabies Team Members Ivan Kuzmin, Charles Rupprecht and Daniel Streicker, who is also with the University of Georgia.

The team made their discovery by analyzing hundreds of rabies viruses in 23 species of bats. In the United States, there are at least 45 different species of bats and many different strains of rabies. Not coincidentally, the CDC collects rabid bats after humans or their pets or livestock may have been exposed to the virus -- adding nearly 2,000 bats annually to its database. McCracken and his colleagues used this database to document the cases in which a rabies virus jumped from one species of bat to another. They verified the cases by genotyping both the viruses and the bats.

The researchers documented over 200 examples of CSTs and analyzed the best explanations for CSTs, such as geographic range, behavior, ecology and genetic relatedness. The study found that the majority of viruses from cross-species infections were tightly nested among genetically similar bat species.

"It turns out, the most important factor in cross-species transmission is how closely related the bat species are," McCracken said. "Our study demonstrates that rapid evolution can be insufficient to overcome phylogenetic barriers at two crucial stages of viral emergence: initial infection and sustained transmission."

This discovery may have significant implications for public health authorities as they try to track where the next infectious disease will emerge. The team's research provides a model for how such diseases transfer from host to host.

"Although CST events are the source of infectious diseases that kill millions of people each year, the natural reservoirs of viruses in wild animals and how they cross species barriers are poorly known and difficult to observe. In this study, rabies in bats serves as a model to understand events that are critical to public health concerns worldwide," McCracken said.

Whitney Holmes | EurekAlert!
Further information:
http://www.utk.edu

Further reports about: CDC CST Ebola Flu Outbreak HIV-AIDS SARS Swine flu evolutionary biology infectious disease rabies

More articles from Life Sciences:

nachricht Rutgers scientists discover 'Legos of life'
23.01.2018 | Rutgers University

nachricht Researchers identify a protein that keeps metastatic breast cancer cells dormant
23.01.2018 | Institute for Research in Biomedicine (IRB Barcelona)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Optical Nanoscope Allows Imaging of Quantum Dots

Physicists have developed a technique based on optical microscopy that can be used to create images of atoms on the nanoscale. In particular, the new method allows the imaging of quantum dots in a semiconductor chip. Together with colleagues from the University of Bochum, scientists from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute reported the findings in the journal Nature Photonics.

Microscopes allow us to see structures that are otherwise invisible to the human eye. However, conventional optical microscopes cannot be used to image...

Im Focus: Artificial agent designs quantum experiments

On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.

We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Rutgers scientists discover 'Legos of life'

23.01.2018 | Life Sciences

Seabed mining could destroy ecosystems

23.01.2018 | Earth Sciences

Transportable laser

23.01.2018 | Physics and Astronomy

VideoLinks Science & Research
Overview of more VideoLinks >>>