32
Short Report
34A large variety of viruses multiply in the honey bee Apis mellifera L. (Allen & Ball, 1996).
35Knowledge of the spreading mechanism of honey bee pathogens within the hive and 36 apiary is essential to our understanding of bee disease dynamics. Among the viruses 37 infecting honey bees, Chronic bee paralysis virus (CBPV) is the causal agent of chronic 38 paralysis known to induce significant losses in honey bee colonies (Ball & Bailey, 1997).
39The pathology is characterized by clusters of trembling, flightless, crawling bees and by 40 individual bees, sometimes hairless, standing at the hive entrance (Bailey et al., 1983). A 41 correlation between chronic paralysis and high viral loads of CBPV was demonstrated 42 particularly in symptomatic bees (Blanchard et al., 2007a). Moderate viral loads were also 43 demonstrated in colonies without symptoms (Blanchard et al., 2007a). To date, CBPV 44 has been detected only in A. mellifera (Allen & Ball, 1996) and the presence of this virus 45 has been observed on every continent (Bailey, 1967 destructor (Ball & Allen, 1988;Tentcheva et al., 2004;Yue & Genersch, 2005). In addition,
50DWV replicative RNA was detected in V. destructor (Yue & Genersch, 2005
63secondly to determine whether the CBPV was able to replicate in these hosts, and thirdly
64to evaluate the genome variability of a partial sequence of CBPV between them.
66Sample collection and preparation, RNA extraction and cDNA synthesis.
67In this study, the honey bees, ants and mites were collected from three apiaries where Five microliters of the cDNA were then used as template for the CBPV TaqMan PCR, or 78 the minus-strand RNA detection.
80Upgrading the CBPV real-time two-step RT-PCR assay.
81A real-time two-step TaqMan RT-PCR assay has recently been developed to quantify the 82 CBPV genomic load in bee samples (Blanchard et al., 2007a). This assay was adapted to
109Unexpectedly, a CBPV genomic load was detected in the mite sample from apiary 1 but
123Given that CBPV is a positive-strand RNA virus, the synthesis of minus-strand CBPV
124RNA is carried out during viral replication. Hence, detection of the minus-strand RNA is 125 indicative of virus replication (Craggs et al., 2001;Yue & Genersch, 2005). A specific RT-
126PCR was developed to assess the presence or absence of minus-strand CBPV RNA in 127 different samples. First strand cDNA was synthesized from the extracted RNA described 128 above, using a minus-strand specific primer. This primer consisted of a tag unrelated to 129 CBPV (lower-case) coupled to a specific primer of CBPV (upper-case) (RT ms CBPV = 130 5'-atcggaatcgcctagcttGCTTGATCTCCTCCTGCTTG-3'). The reverse transcription was
148
Sequence analysis
149The PCR products obtained from the different samples (bees, ants, varroas) were
156
Discussion
157These data show for the first time the presence of CBPV in hosts other than A. mellifera.
158In this study we demonstrated the presence of CBPV in two species of carnivore ants (C.
180This is the first discovery of a bee virus a...