scholarly journals Modelling the spread of infectious salmon anaemia among salmon farms based on seaway distances between farms and genetic relationships between infectious salmon anaemia virus isolates

2011 ◽  
Vol 8 (62) ◽  
pp. 1346-1356 ◽  
Author(s):  
M. Aldrin ◽  
T. M. Lyngstad ◽  
A. B. Kristoffersen ◽  
B. Storvik ◽  
Ø. Borgan ◽  
...  
Keyword(s):  
Genetic Relationships ◽  
Genetic Distances ◽  
Infectious Salmon Anaemia Virus ◽  
Time Data ◽  
Farmed Salmon ◽  
Source Of Infection ◽  
History Of ◽  
Isa Virus ◽  
Virus Isolates ◽  
Infectious Salmon Anaemia

Infectious salmon anaemia (ISA) is an important infectious disease in Atlantic salmon farming causing recurrent epidemic outbreaks worldwide. The focus of this paper is on tracing the spread of ISA among Norwegian salmon farms. To trace transmission pathways for the ISA virus (ISAV), we use phylogenetic relationships between virus isolates in combination with space–time data on disease occurrences. The rate of ISA infection of salmon farms is modelled stochastically, where seaway distances between farms and genetic distances between ISAV isolates from infected farms play prominent roles. The model was fitted to data covering all cohorts of farmed salmon and the history of all farms with ISA between 2003 and summer 2009. Both seaway and genetic distances were significantly associated with the rate of ISA infection. The fitted model predicts that the risk of infection from a neighbourhood infectious farm decreases with increasing seaway distance between the two farms. Furthermore, for a given infected farm with a given ISAV genotype, the source of infection is significantly more likely to be ISAV of a small genetic distance than of moderate or large genetic distances. Nearly half of the farms with ISA in the investigated period are predicted to have been infected by an infectious farm in their neighbourhood, whereas the remaining half of the infected farms had unknown sources. For many of the neighbourhood infected farms, it was possible to point out one or a few infectious farms as the most probable sources of infection. This makes it possible to map probable infection pathways.

scholarly journals Short communication: Evaluation of charged membrane filters and buffers for concentration and recovery of infectious salmon anaemia virus in seawater

PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0253297
Author(s):  
Simon Chioma Weli ◽  
Haitham Tartor ◽  
Bjørn Spilsberg ◽  
Ole Bendik Dale ◽  
Atle Lillehaug
Keyword(s):  
Membrane Filter ◽  
Natural Seawater ◽  
Infectious Salmon Anaemia Virus ◽  
Membrane Filters ◽  
Concentration Method ◽  
Subsequent Elution ◽  
Lysis Buffer ◽  
Farmed Atlantic Salmon ◽  
Isa Virus ◽  
Infectious Salmon Anaemia

Infectious salmon anaemia virus (ISAV) is the cause of an important waterborne disease of farmed Atlantic salmon. Detection of virus in water samples may constitute an alternative method to sacrificing fish for surveillance of fish populations for the presence of ISA-virus. We aimed to evaluate different membrane filters and buffers for concentration and recovery of ISAV in seawater, prior to molecular detection. One litre each of artificial and natural seawater was spiked with ISAV, followed by concentration with different filters and subsequent elution with different buffers. The negatively charged MF hydrophilic membrane filter, combined with NucliSENS® lysis buffer, presented the highest ISAV recovery percentages with 12.5 ± 1.3% by RT-qPCR and 31.7 ± 10.7% by RT-ddPCR. For the positively charged 1 MDS Zeta Plus® Virosorb® membrane filter, combined with NucliSENS® lysis buffer, the ISAV recovery percentages were 3.4 ± 0.1% by RT-qPCR and 10.8 ± 14.2% by RT-ddPCR. The limits of quantification (LOQ) were estimated to be 2.2 x 103 ISAV copies/L of natural seawater for both RT-qPCR and RT-ddPCR. The ISAV concentration method was more efficient in natural seawater.

Evolution of infectious salmon anaemia virus (ISA virus)

2012 ◽  
Vol 157 (12) ◽  
pp. 2309-2326 ◽  
Author(s):  
Heidrun Plarre ◽  
Are Nylund ◽  
Marius Karlsen ◽  
Øyvind Brevik ◽  
Per Anton Sæther ◽  
...  
Keyword(s):  
Infectious Salmon Anaemia Virus ◽  
Isa Virus ◽  
Infectious Salmon Anaemia

In vivo virulence and genomic comparison of infectious Salmon Anaemia Virus isolates from Atlantic Canada

2018 ◽  
Vol 41 (9) ◽  
pp. 1373-1384 ◽  
Author(s):  
Francis LeBlanc ◽  
Steven Leadbeater ◽  
Mark Laflamme ◽  
Nellie Gagné
Keyword(s):  
Atlantic Canada ◽  
Infectious Salmon Anaemia Virus ◽  
Genomic Comparison ◽  
Virus Isolates ◽  
Infectious Salmon Anaemia

Comparative virulence of Infectious salmon anaemia virus isolates in Atlantic salmon,Salmo salarL.

2009 ◽  
Vol 32 (2) ◽  
pp. 157-171 ◽  
Author(s):  
R J Ritchie ◽  
J T McDonald ◽  
B Glebe ◽  
W Young-Lai ◽  
E Johnsen ◽  
...  
Keyword(s):  
Atlantic Salmon ◽  
Infectious Salmon Anaemia Virus ◽  
Virus Isolates ◽  
Infectious Salmon Anaemia

scholarly journals The evolution of hard tick-borne relapsing fever borreliae is correlated with vector species rather than geographical distance

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Ranna Nakao ◽  
Kentaro Kasama ◽  
Bazartseren Boldbaatar ◽  
Yoshitoshi Ogura ◽  
Hiroki Kawabata ◽  
...  
Keyword(s):  
Core Gene ◽  
Genetic Distances ◽  
Hard Tick ◽  
Vector Species ◽  
Relapsing Fever ◽  
Strain Isolation ◽  
Ecological Features ◽  
Geographical Distances ◽  
History Of ◽  
Hokkaido Island

Abstract Background Relapsing fever (RF) borreliae are arthropod-borne spirochetes and some of them cause human diseases, which are characterized by relapsing or recurring episodes of fever. Recently, it has been classified into two groups: soft tick-borne RF (STRF) borreliae and hard tick-borne RF (HTRF) borreliae. STRF borreliae include classical RF agents and HTRF borreliae, the latter of which include B. miyamotoi, a human pathogen recently identified in Eurasia and North America. Results In this study, we determined the genome sequences of 16 HTRF borreliae strains: 15 B. miyamotoi strains (9 from Hokkaido Island, Japan, 3 from Honshu Island, Japan, and 3 from Mongolia) and a Borrelia sp. tHM16w. Chromosomal gene synteny was highly conserved among the HTRF strains sequenced in this study, even though they were isolated from different geographic regions and different tick species. Phylogenetic analysis based on core gene sequences revealed that HTRF and STRF borreliae are clearly distinguishable, with each forming a monophyletic group in the RF borreliae lineage. Moreover, the evolutionary relationships of RF borreliae are consistent with the biological and ecological features of each RF borreliae sublineage and can explain the unique characteristics of Borrelia anserina. In addition, the pairwise genetic distances between HTRF borreliae strains were well correlated with those of vector species rather than with the geographical distances between strain isolation sites. This result suggests that the genetic diversification of HTRF borreliae is attributed to the speciation of vector ticks and that this relationship might be required for efficient transmission of HTRF borreliae within vector ticks. Conclusions The results of the present study, together with those from previous investigations, support the hypothesis that the common ancestor of borreliae was transmitted by hard-bodied ticks and that only STRF borreliae switched to using soft-bodied ticks as a vector, which was followed by the emergence of Borrelia recurrentis, lice-borne RF borreliae. Our study clarifies the phylogenetic relationships between RF borreliae, and the data obtained will contribute to a better understanding of the evolutionary history of RF borreliae.

scholarly journals Molecular and Biological Characterisation of Turnip mosaic virus Isolates Infecting Poppy (Papaver somniferum and P. rhoeas) in Slovakia

Viruses ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 430 ◽  
Author(s):  
Miroslav Glasa ◽  
Katarína Šoltys ◽  
Lukáš Predajňa ◽  
Nina Sihelská ◽  
Slavomíra Nováková ◽  
...  
Keyword(s):  
Mosaic Virus ◽  
Phylogenetic Analyses ◽  
Molecular Data ◽  
Turnip Mosaic Virus ◽  
Biological Assays ◽  
Genetic Complexity ◽  
The World ◽  
History Of ◽  
Virus Isolates

In recent years, the accumulated molecular data of Turnip mosaic virus (TuMV) isolates from various hosts originating from different parts of the world considerably helped to understand the genetic complexity and evolutionary history of the virus. In this work, four complete TuMV genomes (HC9, PK1, MS04, MS15) were characterised from naturally infected cultivated and wild-growing Papaver spp., hosts from which only very scarce data were available previously. Phylogenetic analyses showed the affiliation of Slovak Papaver isolates to the world-B and basal-B groups. The PK1 isolate showed a novel intra-lineage recombination pattern, further confirming the important role of recombination in the shaping of TuMV genetic diversity. Biological assays indicated that the intensity of symptoms in experimentally inoculated oilseed poppy are correlated to TuMV accumulation level in leaves. This is the first report of TuMV in poppy plants in Slovakia.

Sign in / Sign up

Export Citation Format

Share Document