Preliminary observations on possible pathogen spill-over from Apis mellifera to Apis cerana

Abstract

International audiencePopulations of Apis mellifera and Apis cerana in China and Vietnam were surveyed in order to study possible pathogen spill-over from European to Asian honeybees. This is the first survey of the prevalence of honeybee pathogens in apiaries in Vietnam, including pathogen prevalence in wild A. cerana colonies never in contact with A. mellifera. The bee samples were assayed for eight honeybee viruses: deformed wing virus (DWV); black queen cell virus (BQCV); sac brood virus (SBV); acute bee paralysis virus (ABPV); Kashmir bee virus (KBV); Israeli acute paralysis virus (IAPV); chronic bee paralysis virus (CBPV); and slow bee paralysis virus (SBPV), for two gut parasites (Nosema ssp.) and for the causative agent for European foulbrood (Melissococcus plutonius). The Vietnamese samples were assayed for Acarapis woodi infestation. No clear evidence of unique inter-specific transmission of virus infections between the two honeybee species was found. However, in wild A. cerana colonies, the only virus infection detected was DWV. With findings of IAPV infections in Chinese samples of A. cerana colonies in contact with A. mellifera, inter-specific transmission of IAPV cannot be ruled out. BQCV was the most prevalent virus in managed colonies irrespective of bee species. We did not detect the causative agent of European foulbrood, M. plutonius in wild or isolated colonies of A. cerana in Vietnam or China; however, low incidence of this pathogen was found in the Asian host species when in contact with its European sister species. No evidence for the presence of A. woodi was found in the Vietnamese samples

Comparative susceptibility and immune responses of Asian and European honey bees to the American foulbrood pathogen, Paenibacillus larvae

“…Currently, A. mellifera occurs throughout most of the natural distribution area of A. cerana in Asia (Yañez et al, 2015). This has led to interspecific pathogen transmission from A. mellifera to A. cerana (Forsgren et al, 2015;Lin et al, 2016) or vice versa some pathogens also can be spread from native A. cerana to A. mellifera (Rath, 1999;Paxton et al, 2007;Locke et al, 2012). However, little is known about P. larvae incidence in Asiatic cavity-nesting honey bees; Apis cerana (Chen et al, 2000).…”

“…Interspecific transmission of pathogens between different host systems is currently viewed as one of the most essential sources of biodiversity loss and honey bee colony losses in particular (Forsgren et al, 2015). Many studies have reported interspecific transmission of pathogens in different honey bees such as Nosema spp.…”

“…Many studies have reported interspecific transmission of pathogens in different honey bees such as Nosema spp. (Chaimanee & Chantawannakul, 2015), viruses (Li et al, 2012), V. destructor (Hamiduzzaman et al, 2015), and Melissococcus plutonius (Forsgren et al, 2015). Therefore, it could help to better understand how pathogens and parasites contribute within and between species.…”

Parasites, pathogens, and pests of honeybees in Asia

“…Among them, seven are common including BQCV, DWV, KBV, SBV, ABPV, Chronic bee paralysis virus (CBPV), and Israeli acute paralysis virus (IAPV) (Chen and Siede 2007). In Asia, these seven viruses have been reported to infect different honeybee species throughout the region (Sanpa and Chantawannakul 2009;Ai et al 2012;Forsgren et al 2015 Iflaviridae, whereas BQCV, ABPV, KBV, and IAPV belong to the Dicistroviridae.…”

“…In A. cerana , it was observed in India, Thailand, South Korea, Japan, Nepal, China, and Vietnam (Shah and Shah 1988;Allen and Ball 1996;Choi et al 2008;Kojima et al 2011;Grabensteiner et al 2007;Ai et al 2012;Forsgren et al 2015). SBV infection of A. mellifera colonies was detected in Thailand, South Korea, Jap a n , C h i n a , a n d Vi e t n a m ( S a n p a a n d Yoo et al 2009;Kojima et al 2011;Ai et al 2012;Forsgren et al 2015).…”