Disease associations between honeybees and bumblebees as a threat to wild pollinators
据本周《Nature》期刊发表的一份研究显示，导致蜜蜂大量死亡的病原体，原来亦可感染熊蜂和其他传粉昆虫。研究结果证明新发传染病有机会从人工养殖场溜出野外。
西方蜜蜂（Apis mellifera）是一种重要的传粉昆虫，可帮助人类采集花粉和花蜜，但新近出现的病原体，已令全球蜜蜂数目大副下降；养蜂业要在努力的管理下才能保持蜜蜂数目不变，而野生熊蜂（Bombus spp.）的数目更是令人担忧。英国伦敦大学皇家霍洛威学院的Matthias Fürst教授、Mark Brown教授与其科研团队怀疑从人工养殖场溜出的病原体是野蜂数目下降的元凶。
研究人员于是在实验室受控的环境下，进行了蜜蜂互传实验。他们发现两种常见和拥有高杀伤力的蜜蜂病原体——变形翼病毒（deformed wing virus ）和蜜蜂微孢子（Nosema ceranae）—— 能感染野生熊蜂，并缩短其寿命。研究小组随后进行了横跨英国和马恩岛的大规模实地研究，证明这两种病原体已在野外广泛传播。他们不但发现变形翼病毒曾在蜜蜂和熊蜂群中变种，更发现可利用患病蜜蜂数目来推测熊蜂的患病状态。病毒遗传变异分析表明，在同一地方捕捉到的蜜蜂，比在不同地方捕捉到的蜜蜂，拥有更密切相关的病毒株，这发现刚好证明疾病正在传播中。作者表示，数据不能显示出变形翼病毒在蜜蜂和熊蜂之间传染的方向性，但是蜜蜂群中的高发病率已足以证明病毒是感染传粉昆虫的主要元凶。
作者总结时说，要充分认识新发传染病对野生传粉昆虫的危害，我们必须深入认识这些病的流行病学、影响和风险。换句话说，若要减轻突发传染病的威胁，了解野生蜜蜂是重要的第一步。
来源：科学网
Abstract
Emerging infectious diseases (EIDs) pose a risk to human welfare, both directly and indirectly, by affecting managed livestock and wildlife that provide valuable resources and ecosystem services, such as the pollination of crops. Honeybees (Apis mellifera), the prevailing managed insect crop pollinator, suffer from a range of emerging and exotic high-impact pathogens, and population maintenance requires active management by beekeepers to control them. Wild pollinators such as bumblebees (Bombus spp.) are in global decline, one cause of which may be pathogen spillover from managed pollinators like honeybees or commercial colonies of bumblebees. Here we use a combination of infection experiments and landscape-scale field data to show that honeybee EIDs are indeed widespread infectious agents within the pollinator assemblage. The prevalence of deformed wing virus (DWV) and the exotic parasiteNosema ceranae in honeybees and bumblebees is linked; as honeybees have higher DWV prevalence, and sympatric bumblebees and honeybees are infected by the same DWV strains, Apis is the likely source of at least one major EID in wild pollinators. Lessons learned from vertebrates highlight the need for increased pathogen control in managed bee species to maintain wild pollinators, as declines in native pollinators may be caused by interspecies pathogen transmission originating from managed pollinators.
