Infectious bee diseases common and widespread in Finland
The virus studies are only at an early stage, but deformed wing virus, chronic bee paralysis virus, sacbrood virus and black queen cell virus have already been found. In the past, virus diseases in Finnish bees have only been studied from a few samples sent abroad. The Varroa destructor mite was identified in all surveillance areas with the exception of Åland; in Seinäjoki and Jokioinen about 90 per cent of the hives are infected. American foulbrood bacteria were found in all surveillance areas and 30 per cent of apiaries on average. Other diseases found in sick hives were European foulbrood and chalkbrood.
The future apiary inspections after wintering in the spring and during the honey production season in summer will reveal how the disease burden of hives affects their health.
No mass deaths of bee colonies in Finland
Up to now, no mass deaths of bee colonies have been found in Finland. Evira is developing its operation as the national reference laboratory for bee diseases and is also starting to collect information on hive deaths. The EU surveillance programme may possibly continue and also include other causes affecting mortality, such as plant protectants.
The surveillance study implemented in the production year 2012-2013 covers a total of 161 apiaries in different beekeeping areas: Åland, Jokioinen, Kajaani, Kitee and Seinäjoki. The apiaries are inspected three times: in July-August 2012 before wintering, spring 2013 after wintering, and summer 2013 during the honey production season. American foulbrood advisers from the Finnish Beekeepers’ Association have been appointed as inspectors. For laboratory analysis, samples of live bees and honey from all hives were taken during the first visit, and samples will be taken from sick hives during all visits.
The bees are checked for all the most important viruses causing bee diseases: acute bee paralysis virus (ABPV), deformed wing virus (DWV), chronic bee paralysis virus (CBPV), sacbrood virus (SBV), black queen cell virus (BQCV) and Kashmir bee virus (KBV). In addition, theVarroa mite numbers are assessed, as well as the Paenibacillus larvae bacterium in honey, which causes American foulbrood. As well as the above, sick hives are checked for European foulbrood ( Melissococcus plutonius bacterium), nosemosis (microsporidians Nosema apis and N. cerenae), chalkbrood ( Ascosphaera apis fungus), and parasites, such as the tracheal mite ( Acarapis woodi).
The survey is directed by the EU Reference Laboratory for honeybee health. The survey will obtain comparable and reliable information on bee mortality at EU level, as well as clarification on the contribution of infectious diseases to bee mortality.
Professor Sinikka Pelkonen, Head of Unit, Reference Laboratory for bee diseases, Veterinary Bacteriology Research Unit, Evira, t. +358 (0)400 287061.