Genetic Analysis of Israel Acute Paralysis Virus: Distinct Clusters Are Circulating in the United States

Abstract

Israel acute paralysis virus (IAPV) is associated with colony collapse disorder of honey bees. Nonetheless, its role in the pathogenesis of the disorder and its geographic distribution are unclear. Here, we report phylogenetic analysis of IAPV obtained from bees in the United States, Canada, Australia, and Israel and the establishment of diagnostic real-time PCR assays for IAPV detection. Our data indicate the existence of at least three distinct IAPV lineages, two of them circulating in the United States. Analysis of representatives from each proposed lineage suggested the possibility of recombination events and revealed differences in coding sequences that may have implications for virulence.Over the winter of 2006 and 2007, an estimated 23% of all beekeeping operations in the United States experienced losses of hives attributed to colony collapse disorder (CCD) (30). More than 90 cultivated crops depend on the honey bee, Apis mellifera, for pollination; thus, CCD has profound implications for the food supply (23). We recently reported that the presence in hives of the dicistrovirus Israel acute paralysis virus (IAPV) was strongly correlated with the presence of CCD (8).IAPV was first described in 2004 in Israel (21), where infected bees presented with shivering wings, progressed to paralysis, and then died outside the hive. IAPV has features comparable to those of members of the family Dicistroviridae of the superfamily Picornaviridae. Unlike members of the Picornaviridae, which have a single open reading frame (ORF) encoding a single polyprotein, viruses in the family Dicistroviridae have two ORFs encoding two polyproteins. Dicistroviruses have two internal ribosomal entry sites (IRES), one found in the 5Ј untranslated region (UTR) and the other located in the intergenic region between ORF1 and ORF2. Other viruses known to infect honey bees, and related to picornaviruses, are sacbrood virus, deformed wing virus, acute bee paralysis virus (ABPV), Kashmir bee virus (KBV), and black queen cell virus (4, 7).Given the importance of honey bees as pollinators and the reported association between CCD and IAPV, we pursued phylogenetic analysis of geographically discrete IAPV isolates. We report the complete genome sequences of representatives from each of three lineages of IAPV and demonstrate through detailed analysis of four regions of the viral genome (the 5Ј UTR and 5Ј terminus of ORF1; the 3Ј terminus of ORF1, the intergenic region, and the 5Ј terminus of ORF2; ORF2; and the RNA-dependent RNA polymerase [RdRp]) the presence on three continents of at least three clusters of IAPV, two of them currently circulating in the United States. MATERIALS AND METHODSSample collection and RNA extraction. Adult bees were collected from migratory beekeeping operations in the United States with CCD. Diseased apiaries were identified based on evidence of recent collapse of colonies within the apiary and a lack of dead bees in the collapsed colonies. From each colony, 150 adult bees were collected and stored at Ϫ80°C until they w...

Seasonal prevalence of pathogens and parasites in the savannah honeybee (Apis mellifera scutellata)

“…This virus was first diagnosed in Israel, where it reportedly caused large scale honeybee mortality and symptoms included trembling wings and paralysis (Maori et al, 2007;Palacios et al, 2008). The detection of IAPV in Varroa mites sampled during this study is therefore of concern, especially since it was recently confirmed that Varroa mites are capable of transmitting IAPV to honeybees (Di Prisco et al, 2011).…”

Israeli acute paralysis virus associated paralysis symptoms, viral tissue distribution and Dicer-2 induction in bumblebee workers (Bombus terrestris)

“…IAPV is positive single-stranded RNA virus in the family Dicistroviridae with a global distribution range (de Miranda et al, 2010;Maori et al, 2007;Palacios et al, 2008). The nomenclature of this virus is largely based on its symptoms that are similar to ABPV.…”

“…DWV caused crippled wings in bumblebee (Bombus terrestris and Bombus pascuorum) workers even without Varroa (Fürst et al, 2014;Genersch et al, 2006). Interestingly, viral tissue tropism was different between DWV-infected (asymptomatic) and clinically diseased (symptomatic) honeybees and bumblebees, indicating that overt infection may also be associated with virus tissue spreading (Genersch et al, 2006).IAPV is positive single-stranded RNA virus in the family Dicistroviridae with a global distribution range (de Miranda et al, 2010;Maori et al, 2007;Palacios et al, 2008). The nomenclature of this virus is largely based on its symptoms that are similar to ABPV.…”

Short communication. Presence, quantification and phylogeny of Israeli acute paralysis virus of honeybees in Andalusia (Spain)

“…This virus gained prominence after a report in 2007 associated it with the colony collapse disorder (CCD) in the USA, where IAPV presence was considered a statistically significant marker of CCD (Cox-Foster et al, 2007). IAPV has since been described in numerous countries such as China (Xun et al, 2009), Canada and Australia (Palacios et al, 2008), or Argentina (Reynaldi et al, 2011). In Europe, IAPV has been found in France (Blanchard et al, 2008) and more recently in Spain (Kukielka & Sánchez-Vizcaíno, 2010) and Poland (Pohorecka et al, 2011).…”

“…One-step real-time reverse transcription polymerase chain reaction (RTqPCR) was carried out using SYBR-Green dye. Primers targeting a 220-bp region of the gene ORF-2 were used (Palacios et al, 2008), and amplification was done following the thermocycler protocol described by Palacios et al (2008).…”