Virulence of Infectious hematopoietic necrosis virus and Infectious pancreatic necrosis virus coinfection in rainbow trout ( Oncorhynchus mykiss ) and nucleotide sequence analysis of the IHNV glycoprotein gene

Abstract

The outcomes of a coinfection of rainbow trout ( Oncorhynchus mykiss) with Infectious hematopoietic necrosis virus (IHNV) strain S46 and Infectious pancreatic necrosis virus (IPNV) strain S46 was determined after waterborne infection. Trout infected with the IHNV/IPNV.S46 sample, (a mixed sample containing equal infectious titers of the viruses) showed 50% less mortality than fish infected with either of the reference viruses alone. Forty-five days after the coinfection, IPNV antigens were detected by flow cytometry in 49 to 63% of the leukocytes from the surviving trout; whereas, only 9-15.6% of the leukocytes expressed IHNV viral antigens. IPNV was easily detected by reverse transcription-polymerase chain reaction (RT-PCR), whereas, for IHNV, a second step of amplification of a 753 bp fragment corresponding to the internal sequences of the IHNV G gene was necessary to optimize viral detection. The sequence of the IHNV gene involved in virulence, the glycoprotein (G) gene, was determined for the IHNV.S46 and compared with other sequences available in the GenBank. Changes found were not located in the antigenic domains of the glycoprotein and were considered not significant.

Isolation and characterization of a rhabdovirus from co-infection of two viruses in mandarin fish

“…In comparison with the co-infection of IPNV and IHNV in rainbow trout, IPNV and IHNV had been identified and characterized before the co-infection was observed (Alonso et al, 2003), whereas the two viruses coinfected in mandarin fish have not been characterized. In this study, we developed an isolation method by serial dilution of the original viral isolate and single plaque selection, and successfully isolated the rhabdovirus.…”

“…The phenomenon of viral growth inhibition in co-infection of two viruses has been described in the case for IPNV-IHNV co-infection. For example, Alonso et al (1999Alonso et al ( , 2003 demonstrated that IPNV interferes with the replication of IHNV in coinfection experiments of BF2 cells. Chinchar et al (1998) observed that channel catfish reovirus inhibits replication of channel catfish herpesvirus, and proposed possible mechanisms for both interference and induction of interferon-like factors.…”

“…In fish, co-infection cases of two viruses, such as coinfection of infectious pancreatic necrosis virus (IPNV) and infectious hematopoietic necrosis virus (IHNV), and co-infection of infectious salmon anaemia (ISA) virus and a novel togavirus-like virus, were also reported in rainbow trout (LaPatra et al, 1993;Vilas et al, 1994;Alonso et al, 1999Alonso et al, , 2003 and in Atlantic salmon (Kibenge et al, 2000), and most of the studies were focused on the interactions between viruses during double or simultaneous in vitro infection (Alonso et al, 2003;Rodriguez et al, 2005).…”

“Mid-G” Region Sequences of the Glycoprotein Gene of Austrian Infectious Hematopoietic Necrosis Virus Isolates Form Two Lineages within European Isolates and Are Distinct from American and Asian Lineages

“…Coinfections with other rhabdoviruses, e.g., viral hemorrhagic septicemia virus (VHSV), or with viruses of the family Birnaviridae such as infectious pancreatic necrosis virus (IPNV), were observed frequently (1,2,3,10,49).…”

Role of infectious pancreatic necrosis virus (IPNV) infection in co-infections with other viruses

“…Ich badania są zgodne z badaniami Alonso i wsp. (2), którzy stwierdzili aktywną rolę wirusa IPN w obniżeniu namnażania wirusa IHN w liniach komórkowych. W większości badań nad koinfekcją mechanizm wywoływania odporności nie jest zrozumiały i różne czynniki są brane pod uwagę, np.…”