Featured Research

from universities, journals, and other organizations

Salmon Virus With Potential For Change

Date:
April 28, 2009
Source:
Norwegian School of Veterinary Science
Summary:
Infectious salmon anaemia (ISA) is one of the most economically-damaging diseases in Norwegian fish farming industry. It is caused by a marine Orthomyxovirus, the same family that produces the influenza A virus that causes disease in birds and mammals. Researchers have looked at factors of the ISA virus genes that influence its ability to cause disease in salmon.

ISA virus association to cellular membrane.
Credit: Trygve Meum Eliassen

Infectious salmon anaemia (ISA) is one of the most economically-damaging diseases in Norwegian fish farming industry. It is caused by a marine Orthomyxovirus, the same family that produces the influenza A virus that causes disease in birds and mammals. For his doctorate, Turhan Markussen looked at factors of the ISA virus genes that influence its ability to cause disease in salmon.

Infectious salmon anaemia was first recorded in Norway in 1984 and has subsequently appeared in a series of countries around the north Atlantic. In 2008 it was officially confirmed that the disease had also spread to the southern hemisphere, after several large outbreaks in Chile. During the last 25 years, over 460 outbreaks of ISA have been recorded, all of them in farmed salmon.

Around 1990 there was a serious epidemic in Norway, with some 50 - 80 outbreaks annually. Comprehensive preventative measures were introduced and the number of outbreaks was greatly reduced. However, the disease has proven to be difficult to eradicate, and recent years have again seen an increase in the incidence of the disease.

Not all of the ISA virus variants appear to be virulent and the progression of the disease varies from outbreak to outbreak as both the virus and its salmon host fight a struggle to prevail. To be able to develop a vaccine or a treatment regime, it is decisively important to understand the dynamics of this struggle.

Small variations in the genetic material can be of great significance for virulence

One of the goals of Turhan Markussen's doctorate was to map the factors in the genes of the ISA virus that influence its ability to produce disease. Markussen and his colleagues found that even small variations in the genetic material can be of great significance for virulence. Variations in one of the virus's surface proteins, haemagglutinin esterase (HE), was previously been assumed to be an important factor, and the results of this doctorate support that assumption.

This doctorate also revealed that another of the virus's surface proteins, fusion protein (F), is of decisive importance for virulence. Exhaustive analyses of the gene sequence of a series of ISA viruses, isolated both from disease outbreaks and from fish without classical signs of ISA, found an important marker for the virus's virulence in precisely this protein. This result is similar to that found in virulent influenza A viruses.

Viral genes other than those coding for surface proteins were also shown to be significant for the virus's disease-causing abilities. It was shown for the first time that the ISA virus produces substances that inhibit the production of interferons, which are proteins the host uses in its first line of defence.

The results from this doctorate are an important contribution to the understanding of the interaction between the ISA virus and the salmon, and with that to efforts to develop combative measures against the disease.

Cand. Scient. Turhan Markussen defended his Ph. D. thesis, entitled "Molecular determinants of infectious salmon anaemia virus (ISAV) virulence", at the Norwegian School of Veterinary Science on March 19, 2009.


Story Source:

The above story is based on materials provided by Norwegian School of Veterinary Science. Note: Materials may be edited for content and length.


Cite This Page:

Norwegian School of Veterinary Science. "Salmon Virus With Potential For Change." ScienceDaily. ScienceDaily, 28 April 2009. <www.sciencedaily.com/releases/2009/04/090421091737.htm>.
Norwegian School of Veterinary Science. (2009, April 28). Salmon Virus With Potential For Change. ScienceDaily. Retrieved August 2, 2014 from www.sciencedaily.com/releases/2009/04/090421091737.htm
Norwegian School of Veterinary Science. "Salmon Virus With Potential For Change." ScienceDaily. www.sciencedaily.com/releases/2009/04/090421091737.htm (accessed August 2, 2014).

Share This




More Plants & Animals News

Saturday, August 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Pyrenees Orphan Bear Cub Gets Brand New Home

Pyrenees Orphan Bear Cub Gets Brand New Home

AFP (Aug. 1, 2014) The discovery of a bear cub in the Pyrenees mountains made headlines in April 2014. Despire several attempts to find the animal's mother, the cub remained alone. Now, the Pyrenees Conservation Foundation has constructed an enclosure. Duration: 00:31 Video provided by AFP
Powered by NewsLook.com
Ebola Vaccine Might Be Coming, But Where's It Been?

Ebola Vaccine Might Be Coming, But Where's It Been?

Newsy (Aug. 1, 2014) Health officials are working to fast-track a vaccine — the West-African Ebola outbreak has killed more than 700. But why didn't we already have one? Video provided by Newsy
Powered by NewsLook.com
Study Links Certain Birth Control Pills To Breast Cancer

Study Links Certain Birth Control Pills To Breast Cancer

Newsy (Aug. 1, 2014) Previous studies have made the link between birth control and breast cancer, but the latest makes the link to high-estrogen oral contraceptives. Video provided by Newsy
Powered by NewsLook.com
Rare Whale Fossil Pulled from Calif. Backyard

Rare Whale Fossil Pulled from Calif. Backyard

AP (Aug. 1, 2014) A rare whale fossil has been pulled from a Southern California backyard. The 16- to 17-million-year-old baleen whale fossil is one of about 20 baleen whale fossils known to exist. (Aug. 1) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins