Of related interest,  see this 2010 peer reviewed article re. honey bee viruses particularly section 6.2 "Emerging diseases of bees and the international trade." http://nlbeekeeping.ca/data/documents/generschaubert2010.pdf This speaks to the problem of pathogen spread and spillover and deficiencies in statutory disease control through the regulations and processes of the World Organization for Animal health (OIE) Terrestrial Animal Health Code. This is the regulatory framework that the Canadian Food Inspection Agency (CFIA) and our provincial government is obliged to work with. With respect to imports from Western Australia, the CFIA screens for Africanized genetics, Varroosis (all Varroa spp.), Tropilaelaps spp., Small Hive Beetle, Apis cerana, American Foulbrood, and European Foulbrood. Our provincial Animal Health Regulations under the Animal Health Protection Act mention Trachael mite, Varroa (only V. destructor), Greater Wax Moth, and Small Hive Beetle. Neither the feds not the province require screening for viruses. The Genersch and Aubert article explains why.

6.2. Emerging diseases of bees and the international trade

Due to the lack of practical control measures, honey bee viruses do not currently form part of any statutory disease control programme anywhere and no virus disease of the honey bee is mentioned in the World Organization for Animal health (OIE) Terrestrial Animal Health Code. The second reason for the restraint of the OIE in this matter is that the information on the geographical distribution of honey bee viruses and their respective impact is only emerging. Moreover, there is a postulate never mentioned but tacitly accepted by all: when the honey bee was introduced in geographical areas where it had never existed before, it carried with it all its viruses. As an example, the controversy on the native geographical origin of KBV illustrates that this postulate cannot be easily denied [33, 106]. Therefore, since all regions of the world are implicitly considered to be infected with all the major bee viruses – and because no country has demonstrated by appropriate techniques and surveillance that it is free of any particular bee virus, no import limitation (such as quarantine measures) for hive products or bees aimed at preventing any undefined virus invasion would be legitimate. In reality, even in the limited scope of apoideae, there are many examples of unforeseeable transmissions of pathogens between introduced and native species: New Zealand native bumblebees are now hosts to a parasitic nematode and three mite species, all of which are thought to have come from the UK with the original introduction of bees [54] (see also the review by [73]). Conversely, in some parts of the world where the European honey bee is an introduced livestock, a still unknown or a benign pathogen of a native species may switch the host and invade the honey bee population with unforeseeable consequences. International regulation (reviewed by [33]) does not take into account and, therefore, is not suited to prevent this possibility, although this scenario was precisely the first step of the invasion of V. destructor from Asia into all continents (except Australia until now). The well-known consequences of this invasion were and still are huge losses of honey bee colonies due to mite infestation and associated health problems including emerging virus infections.

The small hive beetle (Aethina tumida), another major invasive pest, was first confirmed outside its sub-Saharan native range [76] in the eastern USA in 1996, then in Egypt in 2000 and Australia in 2002 [98]. Now it has been recorded in over 30 USA States demonstrating
its potential to spread rapidly [77, 98]. Within its new range, it has caused considerable damages to colonies and honey-extracting facilities [108]. There are no control methods yet available except emergency short-term treatments of limited efficacy. The small hive beetle may also be a threat to biodiversity by attacking the nests of bumble bees and solitary bees [119]. It is noteworthy to recall that the invasion of an exotic species in an ecosystem is currently viewed as one of the most important causes of biodiversity loss and may lead to host eradication [53].

In the context of the BRAVE project (2005), worldwide specialists in bee pathology and virology observed that: ‘‘Many thought that Varroa was the last great threat to world apiculture but then Aethina came to dinner. We must not take our eyes off the ball. The huge level of colony
losses in Spain reportedly caused by Nosema ceranae is another example. Who would have predicted these?’’ No doubt now that the risk of moving still unknown pests and diseases around the globe with potential disastrous consequences is serious. The most recent example might be the occurrence of severe colony losses in the USA due to CCD with IAPV as a marker and loosely linked to imported bees [45]. Unfortunately, the threat to bee health and bee survival imposed by the global trade of bees and hive products is not recognized as a legitimate reason for limiting the international trade of bees. Pathogens must be identified and described beforehand, their impact on the honey-bee well established, the free status of the country must be proven and continuously monitored. We are far from this level of knowledge and technical competence, thus we must live with an increasing global trade in bees whether we distrust it or not. Obviously, we must be prepared for more emerging bee pathogens including viruses.

             ***********************************************
The BEE-L mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software.  For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html