Good timing Matt,
here is another one.
http://onlinelibrary.wiley.com/doi/10.1111/eva.12169/abstract
david
>>> "Gray, Matt" <[log in to unmask]> 10/07/14 16:45 >>>
GRC:
A new publication and press release below on ranaviruses.
Also, a reminder that the GRC Board attempts to maintain a current list
of ranavirus publications on the GRC website; here is the current list
for 2014:
http://fwf.ag.utk.edu/mgray/ranavirus/2014Publications.htm
As you publish papers, please send an email to Amanda or me so we can
add it to the website.
As promised, our website will be updated soon. Jesse is working with
our website designer (Dr. Peter Bouwma), and hope to have it live in
August. As mentioned previously, we plan to offer membership to the GRC
once it is live, and those that join in 2014 will be deemed “charter
members.”
Also, Tom Waltzek and Jim Wellehan at University of Florida are
beginning the initial planning phases of the 2015 International
Symposium on Ranaviruses. If you would like to be involved in planning
or help with activities during the symposium, please contact Tom or
Jim.
All the Best,
Matt
______________________________________________________________
Matthew J. Gray, Ph.D., Professor
Director, Global Ranavirus Consortium
Associate Director, Center for Wildlife Health
University of Tennessee
274 Ellington Plant Sciences Building
Knoxville, TN 37996-4563
865.974.2740 [ofc] [log in to unmask]
865.974.4714 [fax]
http://fwf.ag.utk.edu/personnel/mgray.htm
For more information about Forestry, Wildlife and Fisheries at UTK,
Please visit http://fwf.ag.utk.edu/ or call 865.974.7126
_____________________________________________________________
From: UT News
Sent: Wednesday, July 09, 2014 1:48 PM
Subject: Study Predicts Ranavirus as Potential New Culprit in Amphibian
Extinctions
July 9, 2014
Study Predicts Ranavirus as Potential New Culprit in Amphibian
Extinctions
KNOXVILLE—Amphibian declines and extinctions around the world have
been linked to an emerging fungal disease called chytridiomycosis, but
new research from the National Institute for Mathematical and
Biological Synthesis (NIMBioS) and the Center for Wildlife Health at the
University of Tennessee, Knoxville, shows that another pathogen,
ranavirus, may also contribute.
In a series of mathematical models, researchers showed that ranavirus,
which causes severe hemorrhage of internal organs in frogs, could cause
extinction of isolated populations of wood frogs if they are exposed to
the virus every few years, a scenario that has been documented in wild
populations.
The most widely distributed amphibian species in North America, wood
frogs have been shown to be highly susceptible to ranavirus infection,
particularly as tadpoles. But little research has been done into how
ranavirus affects frogs at all stages of their life cycle–from egg to
hatchling to tadpole to metamorph, the stage when they emerge as frogs.
Little is also known about how the infection could hasten extinction in
entire populations.
The study, published in the journal EcoHealth, investigates the effect
of ranavirus on the entire life cycle of wood frogs in demographically
isolated populations, where there is no movement of frogs into the
population from surrounding areas. The study can be found by visiting
http://bit.ly/1r8ivPF.
The study used mathematical simulations based on long-term data sets
from wild populations of wood frogs in the eastern United States and
laboratory data on the effects of ranavirus. It determined that the
life stage during which frogs were exposed to ranavirus was one of the
most important factors in predicting extinction and declines.
Extinction was most likely to occur when tadpoles or metamorphs were
exposed to ranaviruyears with exposure every year and 25-44 years with exposure every two
years.
The egg stage had a 57 percent survival rate when exposed to
ranavirus, which was high enough to prevent extinction. Scientists
speculate that eggs have a greater survival rate than other stages
because they are protected by a thick gelatinous membrane that may serve
as a structural barrier or contain antiviral properties.
"Just as the chytrid fungus has decimated frog populations, the
results of our study suggest that ranavirus infection, too, could
contribute to extinction of amphibian populations that are
demographically isolated," said lead author and NIMBioS postdoctoral
fellow Julia Earl.
Amphibians are already considered the most imperiled of vertebrates,
and a third of amphibians are threatened or endangered, according to the
International Union for Conservation of Nature, the main international
body that assesses the conservation status of species.
Disease also may be playing a role in amphibians' extinction. Since
the 1990s, chytridiomycosis, which has been called the worst disease
affecting vertebrate animals in recorded history, has caused massive
die-offs and species extinctions around the world, particularly in
Australia; the Caribbean; and North, Central and South America.
"Ranavirus infections in amphibians have been known since the 1960s,
but it wasn't until the 1980s when we started to see large-scale
die-offs," said collaborating UT scientist and director of the Global
Ranavirus Consortium, Matthew Gray, "Hypothesized mechanisms for
emergence include global transport of novel virus strains during the
commercial trade of cold-blooded animals and an increase in
anthropogenic stressors, such as pesticides, on the landscape."
Once exposed to ranavirus, in susceptible species like wood frogs,
mortality can be as quick as three days. Transmission can occur through
water, direct contact and tadpoles scavenging other dead and infected
frogs. There is no cure or treatment for the disease.
The National Institute for Mathematical and Biological Synthesis is an
NSF-supported center that brings together researchers from around the
world to collaborate across disciplinary boundaries to investigate
solutions to basic and applied problems in the life sciences.
To learn more, visit http://www.nimbios.org. To learn more about this
research, visit http://www.nimbios.org/press/FS_frogs.
---
CUTLINE: Wood frog tadpole hemorrhage from a die-off in Brunswick,
Maine, in which it is estimated more than 200,000 tadpoles died in less
than 24 hours due to ranavirus. Photo credit: Nathaniel Wheelwright.
---
C O N T A C T:
Catherine Crawley (865-974-9350, [log in to unmask])
Whitney Heins (865-974-5460, [log in to unmask])
For more UT news, visit http://tntoday.utk.edu.
See UT faculty, staff and students making news at
http://tntoday.utk.edu/category/in-the-news.
