Fish & Wildlife Disease

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USGS is the lead Federal agency for wildlife disease research and surveillance. Our wildlife health capabilities provide research, information, and technical assistance needed to manage wildlife through disease events. Congress and our partners rely on our science to make informed decisions about fish and wildlife disease policy, planning and management.

AFWA/USGS Webinars

AFWA/USGS Webinars

USGS and the Association for Fish and Wildlife Agencies are co-hosting a webinar series on fish and wildlife disease to keep our partners informed about our current disease research and about how USGS science can support disease management efforts.

View the webinar

USGS Response to White-Nose Syndrome in Bats

USGS Response to White-Nose Syndrome in Bats

USGS science has been a critical part of understanding, and responding to, white-nose syndrome. Learn more about the USGS response in this new fact sheet.

Read it here

News

Date published: September 18, 2018

Science for a Risky World: A USGS Plan for Risk Research and Applications – USGS publishes strategic plan for examining risk

USGS explores opportunities to advance its capabilities in risk assessment, mitigation, and communication in new strategic plan.

Date published: July 5, 2017

Hot new imagery of wintering bats suggests a group behavior for battling white-nose syndrome

Hot new imagery from temperature-sensing cameras suggests that bats who warm up from hibernation together throughout the winter may be better at surviving white nose syndrome, a disease caused by a cold-loving fungus ravaging insect-eating bat populations in the United States and Canada.

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Date published: August 29, 2018
Status: Active

Molecular Characterization of Novel Fish Viruses from Technical Assistance Cases

Viruses occur in many cultured and wild stocks of fish. William Batts collaborates with many government, state, tribal, and private research and diagnostic laboratories to aid in identification of these unknown replicating agents of uncertain pathogenicity. Typically, viruses can be replicated in a variety of fish cell lines and investigated at several temperatures to see if the cytopathic...

Contacts: William N Batts
Date published: August 20, 2018
Status: Active

Investigation and Disease Prevention of Spring Viremia of Carp Virus (SVCV)

There has been long history of disease outbreaks and economic losses in wild and farmed carp species due to SVCV. Formerly thought to be restricted to Europe and Asia, SVCV was detected for the first time in North America from diseased koi at a North Carolina fish farm in 2002, and there were extensive eradication efforts with 135,000 fish euthanized in addition to the ~15,000 that died from...

Date published: July 24, 2018
Status: Active

Avian Influenza

Avian influenza is a viral disease caused by various strains of avian influenza viruses that can be classified as low pathogenic avian influenza (LPAI) or highly pathogenic avian influenza (HPAI).  It remains a global disease with potential high consequence with the potential to threaten wildlife, agriculture, and human health. 

Date published: July 24, 2018
Status: Active

Avian Influenza Surveillance

The USGS National Wildlife Health Center (NWHC) serves on the U.S. Interagency Steering Committee for Surveillance for Highly Pathogenic Avian Influenza in Wild Birds to standardize surveillance for this disease and is a leading partner in conducting morbidity and mortality investigations in support of the Interagency Strategic Plan for Early Detection and Monitoring for Avian Influenzas of...

Date published: July 23, 2018
Status: Active

Index of Wildlife Disease Information Resources

The USGS National Wildlife Health Center (NWHC) provides the following index of wildlife disease information resources as a starting point to learn about selected wildlife diseases. The index includes informational web pages and communications and outreach products from the NWHC. To search for scientific literature, please visit the USGS Publications...

Date published: June 1, 2018
Status: Active

Avian Botulism

Botulism is a natural toxin produced by a bacterium ( Clostridium botulinum ) commonly found in the soil. There are several types of botulism toxin some of which can affect humans who eat improperly canned foods. Birds get their own kind of botulism (Type C in Hawaii) that does not affect humans. Botulism type C is concentrated in aquatic invertebrates that filter feed sediments or...

Contacts: Thierry M Work
Date published: June 1, 2018
Status: Active

Toxoplasmosis

Toxoplasmosis is caused by a microscopic parasites called a protozoan. The specific name of the protozoan that causes toxoplasmosis is Toxoplasma gondiiT. gondii reproduces in the gut of cats (all members of the Felidae are susceptible). Cats shed the parasite in their feces, and the parasite is ingested by other animals (intermediate hosts) causing disease. Cats can...

Contacts: Thierry M Work
Date published: May 25, 2018
Status: Active

Disease Ecology and Modeling

The USGS National Wildlife Health Center (NWHC) provides quantitative support and technical assistance to state and federal wildlife managers and partners to better understand or predict the impact of disease on wildlife populations.

Date published: May 24, 2018
Status: Active

Vaccines

The USGS National Wildlife Health Center (NWHC) works on developing various disease management tools, including the development of vaccines. Our current work focuses on vaccines for sylvatic plague, white-nose syndrome, and rabies as disease control strategies.

Contacts: Tonie Rocke
Date published: May 23, 2018
Status: Active

Technology Development and Innovation

To provide the next generation of wildlife disease tools, that can move past detection and documentation and towards solutions for wildlife disease problems, the National Wildlife Health Center (NWHC) is developing a suite of new or adapted technology. Primarily, these technologies focus on three areas of improvement in the realm of wildlife disease: prediction and prevention, surveillance for...

Date published: May 18, 2018
Status: Active

Report Mortality Events and Submit Specimens

Find all required forms, instructions, and guidelines for submitting specimens to the USGS National Wildlife Health Center (NWHC).

Date published: April 10, 2018
Status: Active

Batrachochytrium salamandrivorans (Bsal) Surveillance

Scientists of the USGS National Wildlife Health Center (NWHC) in collaboration with partners have developed risk assessments for Batrachochytrium salamandrivorans (Bsal) in the United States and have begun sampling high-risk locations for the fungus.

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Date published: July 1, 2018

Wildlife Health Bulletins

Wildlife Health Bulletins are distributed to natural resource/conservation agencies to provide and promote information exchange about significant wildlife health threats. 

Date published: March 13, 2018

Wildlife Health Information Sharing Partnership – event reporting system (WHISPers)

The NWHC developed the Wildlife Health Information Sharing Partnership – event reporting system (WHISPers) to increase public awareness of wildlife disease events and promote collaboration and data sharing among wildlife professionals. It is a partner driven tool that provides a dynamic, timely, searchable web-based system for visualizing and accessing data on wildlife disease events...

Date published: March 6, 2018

Weighted Surveillance for Detection of Chronic Wasting Disease

This application provides an easy-to-use interface for conducting weighted surveillance for chronic wasting disease (CWD) in white-tailed deer populations. The first tool called 'Design' is used for planning weighted surveillance activities. The second tool called 'Estimation' is for use after sampling for CWD detection has occurred and no positive cases were found.

Date published: March 2, 2018

Field Manual of Wildlife Diseases

Access field manual resources from the National Wildlife Health Center.

Date published: March 1, 2018

Quarterly Mortality Reports

National Wildlife Health Center produces quarterly mortality reports, containing information about wildlife mortality events throughout the United States and on occasion across North America.

Date published: February 1, 2018

NWHC Reports to AFWA and WAFWA

Access NWHC reports to the Association of Fish and Wildlife Agencies and the Western Association of Fish and Wildlife Agencies.

Date published: January 15, 2018

Medical Wallet Card for Wildlife Professionals

Biologists working with wildlife may be exposed to a variety of disease agents. NWHC has developed a wallet card that wildlife professionals can carry with them to alert medical personnel about potential exposure to zoonotic diseases. Contact information is provided for the Centers for Disease Control for the occurrence of zoonotic diseases in humans.

Date published: January 1, 2018

List of Species Affected by H5N1 (Avian Influenza)

List of species affected by H5N1 avian influenza (excel file).

Date published: July 27, 2017

An Online Database for IHN Virus in Pacific Salmonid Fish: MEAP-IHNV

The Molecular Epidemiology of Aquatic Pathogens (MEAP)-IHNV Database

The MEAP-IHNV database provides access to detailed data for anyone interested in IHNV molecular epidemiology, such as fish health professionals, fish culture facility managers, and academic researchers.

Date published: July 6, 2017

Standardization and Application of an Index of Community Integrity for Waterbirds in the Chesapeake Bay

This data set is comprised of five files related to the modification and scoring of Index of Waterbird Community Integrity (IWCI) scores for all waterbirds of the Chesapeake Bay. One Excel file (A) contains a list of 100+ Chesapeake waterbird species and their species attribute and IWCI scores.

Date published: March 28, 2017

Low-pathogenic avian influenza viruses in wild migratory waterfowl in a region of high poultry production, Delmarva, Maryland

This data set is comprised of four files related to the biosurveillance of low pathogenic avian influenza viruses (LPAIV) in migratory waterfowl at 22 locations in the Maryland portion of the Delmarva Peninsula in fall/winter of 2013-2014. 

Date published: January 1, 2011

Lake Michigan Volunteer AMBLE – Avian Monitoring for Botulism Lakeshore Events

The National Wildlife Health Center, with help from partners and support from the Great Lakes Restoration Initiative, organized “Lake Michigan Volunteer AMBLE – Avian Monitoring for Botulism Lakeshore Events” in 2011. The goal of AMBLE was to empower concerned citizens to monitor bird health and beach conditions along the Lake Michigan shoreline, thus increasing knowledge of avian botulism...

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Date published: July 5, 2018

Wildlife Health Information Sharing Partnership – event reporting system (WHISPers)

The NWHC developed the Wildlife Health Information Sharing Partnership – event reporting system (WHISPers) to increase public awareness of wildlife disease events and promote collaboration and data sharing among wildlife professionals. It is a partner driven tool that provides a dynamic, timely, searchable web-based system for visualizing and accessing data on wildlife disease events nationwide.

Date published: July 2, 2018

White-Nose Syndrome Occurrence Map

View current and archived maps of white-nose syndrome occurrence by county/district.

Date published: May 1, 2018

Chronic Wasting Disease Map

Reported distribution of chronic wasting disease (CWD) in North America. 

Date published: April 3, 2018

Sea Star Wasting Syndrome Map

The map includes information from Pacific Rocky Intertidal Monitoring surveys as well as information from logs submitted by other researchers, divers, and the general public.

Date published: February 17, 2016

Bsal Risk by County

Heat map of the United States showing the total relative risk of Bsal to native US salamanders based on the introduction and consequences assessment (Richgels et. al. 2016).

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Year Published: 2018

A snapshot of women of the U.S. Geological Survey in STEM and related careers

IntroductionThe term “STEM” has been used to group together the fields of science, technology, engineering, and mathematics and to describe education and professions related to these fields. The professional fields connected to STEM education are thought of as engineering, medicine, and computer technology. Yet these professional fields are merely...

Aragon-Long, Susan C.; Burkett, Virginia R.; Weyers, Holly S.; Haig, Susan M.; Davenport, Marjorie S.; Warner, Kelly L.
Aragon-Long, S.C., Burkett, V.R., Weyers, H.S., Haig, S.M., Davenport, M.S., and Warner, K.L., 2018, A snapshot of women of the U.S. Geological Survey in STEM and related careers: U.S. Geological Survey Circular 1443, 100 p., https://doi.org/10.3133/cir1443.

Year Published: 2018

U.S. Geological Survey response to white-nose syndrome in bats

OverviewSince its discovery in 2007, the fungal disease known as white-nose syndrome (WNS) has killed more than six million bats. Ten of 47 bat species have been affected by WNS across 32 States and 5 Canadian Provinces. The cold-growing fungus (Pseudogymnoascus destructans) that causes WNS infects skin covering the muzzle, ears, and wings of...

Hopkins, M. Camille ; Soileau, Suzanna C.
Hopkins, M.C., and Soileau, S.C., 2018, U.S. Geological Survey response to white-nose syndrome in bats: U.S. Geological Survey Fact Sheet 2018–3020, 4 p., https://doi.org/10.3133/fs20183020.

Year Published: 2018

Infection by Nanophyetus salmincola and toxic contaminant exposure in out‐migrating steelhead from Puget Sound, Washington: Implications for early marine survival

Out‐migrating steelhead Oncorhynchus mykiss from four Puget Sound rivers and associated marine basins of Puget Sound in Washington State were examined for the parasite, Nanophyetus salmincola in 2014 to determine whether recent trends in reduced marine survival are associated with the presence of this pathogen. A subset of...

Chen, M.F.; O'Neill, S. M.; Carey, A. J.; Conrad, R. H.; Stewart, B. A.; Snekvik, K. R.; Ylitalo, G. M.; Hershberger, Paul
Chen, M.F., S.M. O’Neill, A.J. Carey, R.H. Conrad, B.A. Stewart, K.R. Snekvik, G.M. Ylitalo, and P.K. Hershberger. 2018. Infection by Nanophyetus salmincola and toxic contaminant exposure in out‐migrating steelhead from Puget Sound, Washington: Implications for early marine survival. J. Aquat Anim Health 30(2): 103-118.

Year Published: 2018

An epidemiological model of virus transmission in salmonid fishes of the Columbia River Basin

We have developed a dynamic epidemiological model informed by records of viral presence and genotypes to evaluate potential transmission routes maintaining a viral pathogen in economically and culturally important anadromous fish populations. In the Columbia River Basin, infectious hematopoietic necrosis virus (IHNV) causes severe disease,...

Ferguson, Paige F. B.; Breyta, Rachel; Brito, Ilana L.; Kurath, Gael; LaDeau, Shannon L.
Ferguson, P.F.B., R. Breyta, I. Brito, G. Kurath, and S.L. LaDeau. 2018. An epidemiological model of virus transmission in salmonid fishes of the Columbia River Basin. Ecol. Model. 377: 1-15.

Year Published: 2018

High‐prevalence and low‐intensity Ichthyophonus infections in Pacific Halibut

Ichthyophonus occurred at high prevalence but low intensity in Pacific Halibut Hippoglossus stenolepis throughout the West Coast of North America, ranging from coastal Oregon to the Bering Sea. Infection prevalence in adults was variable on spatial and temporal scales, with the lowest prevalence typically occurring on the edges of...

Hershberger, Paul; Gregg, Jacob L.; Dykstra, Claude L.
Hershberger, P.K. J.L. Gregg and C.L. Dykstra. High-prevalence and low-intensity Ichthyophonus infections in Pacific Halibut. J. Aquat. Anim. Health 30(1): 13-19

Year Published: 2018

Imperfect pathogen detection from non-invasive skin swabs biases disease inference

1. Conservation managers rely on accurate estimates of disease parameters, such as pathogen prevalence and infection intensity, to assess disease status of a host population. However, these disease metrics may be biased if low-level infection intensities are missed by sampling methods or laboratory diagnostic tests. These false negatives...

DiRenzo, Graziella V.; Grant, Evan H. Campbell; Longo, Ana; Che-Castaldo, Christian; Zamudio, Kelly R.; Lips, Karen
DiRenzo, G. V., Grant, E. H. C., Longo, A. V., Che-Castaldo, C., Zamudio, K. R., and Lips, K. R., 2018, Imperfect pathogen detection from non-invasive skin swabs biases disease inference: Methods in Ecology and Evolution, v. 9, no. 2, p. 380-389. https://doi.org/10.1111/2041-210X.12868

Year Published: 2018

Molecular testing of adult Pacific salmon and trout (Oncorhynchus spp.) for several RNA viruses demonstrates widespread distribution of piscine orthoreovirus in Alaska and Washington

This research was initiated in conjunction with a systematic, multiagency surveillance effort in the United States (U.S.) in response to reported findings of infectious salmon anaemia virus (ISAV) RNA in British Columbia, Canada. In the systematic surveillance study reported in a companion paper, tissues from various salmonids taken from...

Purcell, Maureen; Thompson, Rachel L.; Evered, Joy; Kerwin, John; Meyers, Ted R.; Stewart, Bruce; Winton, James
Purcell, M.K., R.L. Powers, J. Evered, J. Kerwin, T.R. Meyers, B. Stewart, and J.R. Winton. 2017. Molecular testing of adult Pacific salmon and trout (Oncorhynchus spp.) for several RNA viruses demonstrates widespread distribution of piscine orthoreovirus in Alaska and Washington. J. Fish Dis. 41(2): 347-355. DOI: 10.1111/jfd.12740.

Year Published: 2018

Virulence of a chimeric recombinant infectious haematopoietic necrosis virus expressing the spring viraemia of carp virus glycoprotein in salmonid and cyprinid fish

Infectious haematopoietic necrosis virus (IHNV) and spring viraemia of carp virus (SVCV) are both rhabdoviruses of fish, listed as notifiable disease agents by the World Organization for Animal Health. Recombinant rhabdoviruses with heterologous gene substitutions have been engineered to study genetic determinants and assess the potential of these...

Emmenegger, Eveline; Biacchesi, Stéphane; Mérour, Emilie; Glenn, Jolene. A; Palmer, Alexander D.; Brémont, Michel; Kurath, Gael
Emmenegger, E.J., S. Biacchesi, E. Mérour, J.A. Glenn, A.D. Palmer, M. Brémont, and G. Kurath. 2017. Virulence of a chimeric recombinant infectious haematopoietic necrosis virus expressing the spring viraemia of carp virus glycoprotein in salmonid and cyprinid fish. J. Fish Dis. 41(1): 67-78. DOI: 10.1111/jfd.12678.

Year Published: 2018

Land use diversification and intensification on elk winter range in Greater Yellowstone: A framework and agenda for social-ecological research

Amenity migration describes the movement of peoples to rural landscapes and the transition toward tourism and recreation and away from production-oriented land uses (ranching, timber harvesting). The resulting mosaic of land uses and community structures has important consequences for wildlife and their management. This research note examines...

Haggerty, Julia Hobson; Epstein, Kathleen; Stone, Michael; Cross, Paul

Year Published: 2017

Observations and first reports of saprolegniosis in Aanaakłiq, broad whitefish (Coregonus nasus), from the Colville River near Nuiqsut, Alaska

We report the first confirmed cases (2013–2016) of saprolegniosis caused by water mold from the genus Saprolegnia in Aanaakłiq, broad whitefish (Coregonus nasus), from the Colville River near Nuiqsut, Alaska. While this mold is known to be worldwide, these instances represent the first cases in Nuiqsut and only the second instance on a...

Sformo, Todd L.; Adams, Billy; Seigle, John C.; Ferguson, Jayde A.; Purcell, Maureen; Stimmelmayr, Raphaela; Welch, Joseph H.; Ellis, Leah M.; Leppi, Jason C.; George, John C.
Sformo, T.L., B. Adams, J.C. Seigle, J.A. Ferguson, M.K. Purcell, R. Stimmelmayr, J.H. Welch, L.M. Ellis, J.C. Leppi, and J.C. George. 2017. Observations and first reports of saprolegniosis in Aanaakłiq, broad whitefish (Coregonus nasus), from the Colville River near Nuiqsut, Alaska. Polar Sci. 14: 78-82. DOI: 10.1016/j.polar.2017.07.002.

Year Published: 2017

Vaccine effects on heterogeneity in susceptibility and implications for population health management

Heterogeneity in host susceptibility is a key determinant of infectious disease dynamics but is rarely accounted for in assessment of disease control measures. Understanding how susceptibility is distributed in populations, and how control measures change this distribution, is integral to predicting the course of epidemics with and without...

Bansal, Shweta; Pettigrew, Melinda M.; Langwig, Kate E.; Wargo, Andrew R.; Jones, Darbi R.; Viss, Jessie R.; Rutan, Barbara J.; Egan, Nicholas A.; Sá-Guimarães, Pedro; Min Sun Kim; Kurath, Gael; Gomes, M. Gabriela M.; Lipsitch, Marc
Langwig, K.E., A.R. Wargo, D.R. Jones, J.R. Viss, B.J. Rutan, N.A. Egan, P. Sá-Guimarães, M. S. Kim, G. Kurath, M.G.M. Gomes, and M. Lipsitch. 2017. Vaccine effects on heterogeneity in susceptibility and implications for population health management. mBio 8(6):e00796-17. DOI: 10.1128/mBio.00796-17.

Year Published: 2017

Complete sequences of 4 viral hemorrhagic septicemia virus IVb isolates and their virulence in northern pike fry

Four viral hemorrhagic septicemia virus (VHSV) genotype IVb isolates were sequenced, their genetic variation explored, and comparative virulence assayed with experimental infections of northern pike Esox lucius fry. In addition to the type strain MI03, the complete 11183 bp genome of the first round goby Neogobius melanostomus ...

Getchell, Rodman G.; Cornwell, Emily R.; Bogdanowicz, Steven; Andres, Jose; Batts, William N.; Kurath, Gael; Breyta, Rachel; Choi, Joanna G.; Farrell, John M.; Bowser, Paul R.
Getchell, R.G., E.R. Cornwell, S. Bogdanowicz, J. Andrés, W.N. Batts, G. Kurath, R. Breyta, J.G. Choi, J.M. Farrell, and P.R. Bowser. 2017. Complete sequences of 4 viral hemorrhagic septicemia virus IVb isolates and their virulence in northern pike fry. Diseases of Aquatic Organisms 126(3): 211-227. DOI: 10.3354/dao03171.

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chronic wasting disease map Jan 2018
January 1, 2018

Chronic Wasting Disease map Jan 2018

Reported distribution of chronic wasting disease (CWD) in North America in 2017: 24 States and 2 Canadian Provinces have reported the disease in free-ranging and captive cervids.

Hibernating little brown bat
December 31, 2017

Hibernating little brown bat

little brown bat (Myotis lucifugus) with white-nose syndrome hibernating in a Virginia cave during late spring of 2016. Patches of the fungus that causes white-nose syndrome can be seen growing out of the skin (white areas) near the nose and across the folded wing skin of this bat.  Spherical drops of water condensation coat the bat's outer fur, a

...
bat with left wing spread open
May 31, 2017

Examining a bat's wing for white-nose syndrome in Washington

Researchers examine a bat (Myotis sp.) to test for the fungus that causes white-nose syndrome.

August 21, 2015

A2 East Transect – 2015

Permanent Site: A2 East Transect; Depth: 12.4 Meters (Feet 40.8); Distance from river mouth: Kilometers 1.8 (1.1 Miles); Pre/Post Dam Removal: 4 years post-dam removal; Lat/Long: 48.14130295, -123.58766124; Site Description: One of our deeper sites at over 40 feet. Sediment is primarily sand/sandy mud. Seaweeds have returned, mainly bull kelp Nereocystis luetkeana (0:14, 0

...
December 31, 2014

Bat Thermal Video

Imagery from temperature-sensing cameras showing bats in hibernation. This new footage suggests that bats who warm up from hibernation together throughout the winter may be better at surviving white nose syndrome, a disease caused by a cold-loving fungus ravaging insect-eating bat populations in the United States and Canada. Locations: Gap Cave,125 Cumberland Gap National

...
Scientist taking enivornmental swab from the side of a cave.
August 3, 2012

Scientist taking environmental sample during WNS surveillance

Scientist taking environmental samples during white-nose syndrome surveillance activities. Lawrence County, OH. August 2012.

Scientist taking sample from the ground with a spoon.
July 24, 2012

Scientist taking environmental samples during WNS surveillance

Scientist taking environmental samples during white-nose syndrome surveillance activities. Breckinridge County, IN. July 2012.

Scientist holding bat while swab is taken from the wing of the bat.
July 18, 2012

Scientist taking a skin swab sample to test for presence of Pd

Scientist taking a skin swab sample to test for presence of Pd.  Monroe County, IN. July 18, 2012.

Bats affected with white-nose syndrome on cave wall.
April 2, 2008

Affected WNS bats in MA mine

Affected WNS bats in MA mine 2008.

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Date published: September 18, 2018

Science for a Risky World: A USGS Plan for Risk Research and Applications – USGS publishes strategic plan for examining risk

USGS explores opportunities to advance its capabilities in risk assessment, mitigation, and communication in new strategic plan.

Date published: July 5, 2017

Hot new imagery of wintering bats suggests a group behavior for battling white-nose syndrome

Hot new imagery from temperature-sensing cameras suggests that bats who warm up from hibernation together throughout the winter may be better at surviving white nose syndrome, a disease caused by a cold-loving fungus ravaging insect-eating bat populations in the United States and Canada.

Date published: July 11, 2016

EarthWord–Morbidity

When you’re not dead yet, but aren’t feeling well either, there’s an EarthWord for that...

Date published: January 5, 2016

Western Fisheries Science News, December 2015 | Issue 3.12

How Infectious Hematopoietic Necrosis (IHN) Got its Name

Date published: September 15, 2015

Science Confirms Successful Strategy to Protect Threatened Steelhead from Virus

A new and highly effective approach to control a viral pathogen that affects threatened steelhead trout in an Idaho hatchery is documented in a new paper.

Date published: July 6, 2015

Western Fisheries Science News, June 2015 | Issue 3.6

Genetic Analysis Finds that Erythrocytic Necrosis Virus (ENV) of Pacific Herring is an Iridovirus That May be Closely Related to Erythrocytic Viruses of Reptiles