Transmission Pathways of the VNN Introduced in Croatian Marine Aquaculture

Due to the insufficient capacity of Croatian hatcheries, marine aquaculture depends on the importation of fry from different countries in the Mediterranean basin. Importation enables a risk of spreading pathogenic agents. Viral nervous necrosis (VNN), caused by betanodavirus is devastating for the farming of European sea bass. We described a VNN outbreak that occurred in Croatia in 2014. After the diagnosis of VNN in sea bass fry introduced from the same hatchery to five unconnected marine farms at the Adriatic Coast, we performed surveillance within one of the affected farms. It resulted in proven horizontal spreading of the virus within the farm and to feral fish around farm cages. Real-time RT-PCR tested samples showed the dependence of the virus' proliferation to the water temperature and the fish age. The highest mortality rates were noted during higher sea temperatures. Phylogenetic analysis of partial sequences of RNA1 and RNA2 supported the hypothesis that the virus was introduced to all studied farms from the same hatchery. Moreover, phylogenetic analysis of the whole genome sequences of infected farmed sea bass and thicklip mullet showed high similarity and it is unlikely that infection in Croatian sea bass farms has originated from wild reservoirs, as the first positive record in wild mullet was recorded after the disease outbreak.

Medienart:

E-Artikel

Erscheinungsjahr:

2022

Erschienen:

2022

Enthalten in:

Zur Gesamtaufnahme - volume:11

Enthalten in:

Pathogens (Basel, Switzerland) - 11(2022), 4 vom: 30. März

Sprache:

Englisch

Beteiligte Personen:

Zrnčić, Snježana [VerfasserIn]
Brnić, Dragan [VerfasserIn]
Panzarin, Valentina [VerfasserIn]
Abbadi, Miriam [VerfasserIn]
Lojkić, Ivana [VerfasserIn]
Zupičić, Ivana Giovanna [VerfasserIn]
Oraić, Dražen [VerfasserIn]

Links:

Volltext

Themen:

Epidemiology
European sea bass
Feral fish
Journal Article
Phylogenetic analysis
Surveillance
VNN

Anmerkungen:

Date Revised 16.07.2022

published: Electronic

Citation Status PubMed-not-MEDLINE

doi:

10.3390/pathogens11040418

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM339852658