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

• Published in: PloS one Vol. 16; no. 6; p. e0253297
• Main Authors: Weli, Simon Chioma, Tartor, Haitham, Spilsberg, Bjørn, Dale, Ole Bendik, Lillehaug, Atle
• Format: Journal Article
• Language: English
• Published: San Francisco Public Library of Science 16.06.2021; Public Library of Science (PLoS)
• Subjects: Anemia; Aquatic animals; Artificial seawater; Astacus astacus; Biology and Life Sciences; Chemical analysis; Clinical trials; Control methods; Crayfish; Diagnosis; Dilution; Droplets; Earth Sciences; Ecology and Environmental Sciences; Environmental DNA; Epidemics; Farms; Filters; Health aspects; Horizontal transfer; Laboratories; Laboratory experiments; Lakes; Medicine and Health Sciences; Membrane filters; Membranes; Plague; Polymerase chain reaction; Properties; Recovery (Medical); Research and Analysis Methods; RNA-directed DNA polymerase; Salmo salar; Salmon; Salts; Sea-water; Seawater; Surveillance; Viruses; Water analysis; Water sampling; Waterborne infections; Norway; United Kingdom > UK; France; United States > US
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0253297

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 10 3 ISAV copies/L of natural seawater for both RT-qPCR and RT-ddPCR. The ISAV concentration method was more efficient in natural seawater.