Prevalence and Seasonal Variations of Six Bee Viruses in Apis mellifera L. and Varroa destructor Mite Populations in France

Abstract

A survey of six bee viruses on a large geographic scale was undertaken by using seemingly healthy bee colonies and the PCR technique. Samples of adult bees and pupae were collected from 36 apiaries in the spring, summer, and autumn during 2002. Varroa destructor samples were collected at the end of summer following acaricide treatment. In adult bees, during the year deformed wing virus (DWV) was found at least once in 97% of the apiaries, sacbrood virus (SBV) was found in 86% of the apiaries, chronic bee paralysis virus (CBPV) was found in 28% of the apiaries, acute bee paralysis virus (ABPV) was found in 58% of the apiaries, black queen cell virus (BQCV) was found in 86% of the apiaries, and Kashmir bee virus (KBV) was found in 17% of the apiaries. For pupae, the following frequencies were obtained: DWV, 94% of the apiaries; SBV, 80% of the apiaries; CBPV, none of the apiaries; ABPV, 23% of the apiaries; BQCV, 23% of the apiaries; and KBV, 6% of the apiaries. In Varroa samples, the following four viruses were identified: DWV (100% of the apiaries), SBV (45% of the apiaries), ABPV (36% of the apiaries), and KBV (5% of the apiaries). The latter findings support the putative role of mites in transmitting these viruses. Taken together, these data indicate that bee virus infections occur persistently in bee populations despite the lack of clinical signs, suggesting that colony disease outbreaks might result from environmental factors that lead to activation of viral replication in bees.

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

“…BQCV presence in honeybees only and not in Varroa mites is similar to results obtained in France (Tentcheva et al, 2004a) and Hungary (Forgach et al, 2008). Evidence from our and previous studies suggest that Varroa mites might not play a major role in transmitting this virus (Ball and Allen 1988;Carreck et al, 2002;Forgach et al, 2008;Locke et al, 2012;Ribière et al, 2008;Tentcheva et al, 2004a). However, BQCV was detected in Varroa mites from an apiary in Thailand (Chantawannakul et al, 2006) and it was found that Varroa mites can be vectors of BQCV (Ball, 1989;Johns, 2003).…”

“…In this study, a total of eight apiaries tested positive for BQCV of which two of these apiaries also tested positive for N. apis (25% cooccurrence), thus only partly supporting an association between these pathogens. BQCV presence in honeybees only and not in Varroa mites is similar to results obtained in France (Tentcheva et al, 2004a) and Hungary (Forgach et al, 2008). Evidence from our and previous studies suggest that Varroa mites might not play a major role in transmitting this virus (Ball and Allen 1988;Carreck et al, 2002;Forgach et al, 2008;Locke et al, 2012;Ribière et al, 2008;Tentcheva et al, 2004a).…”

“…The absence of DWV from the honeybee and Varroa mite samples collected during this study was unexpected given its high prevalence in apiaries around the world (Allen and Ball, 1996;Baker and Schroeder, 2008;Berényi et al, 2006;Chen and Siede, 2007;Ellis and Munn, 2005;Martin et al, 1998;Tentcheva et al, 2004a) and the close association of DWV with Varroa mites (Bailey and Ball, 1991;Bowen-Walker et al, 1999;Dainat et al, 2012a;Gisder et al, 2009;Martin et al, 2012;Yang and CoxFoster, 2005;Yue and Genersch, 2005). Recently, DWV was also found to be absent from wild A. m. scutellata drones collected in a South African Nature Reserve and honeybee samples from Uganda (Kajobe et al, 2010).…”

“…BQCV was also detected throughout the year in French apiaries (Tentcheva et al, 2004a). BQCV is closely associated with N. apis and the co-occurrence of these two pathogens can reduce the lifespan of infected adult honeybees (Allen and Ball, 1996;Bailey et al, 1983).…”

First detection of viruses in africanized honey bees from Peru

“…These viruses were detected in 70% and 40% of the colonies, respectively. Although our sample size is rather small, those viruses show similar infection rates with a large-scale survey made at same season in a template climatic region (Tentcheva D, et al, 2004). In contrast, virus surveys of Africanized honey bees performed at a different season in Brazil (Teixeira E W, et al, 2008;Teixeira E W, et al, 2012) showed similar rates for BQCV (37%), lower rates for DWV (20.3%) and the detection of ABPV (27%) and IAPV (25%).…”