Robert Brenchley wrote:

> Thanks for the answers to my query. The only thing is, both the main
> factors mentioned so far - cell size and colony density - also applied in the
> UK, and we didn't have an epidemic. It's possible, of course, that acarine
> disease may have reduced colony density here before another factor - such as
> cell size increases - came into play. ..

I'm rather slow to respond to this post, but it may be worth mentioning
that AFB was also a big problem in the UK in the first half of the last
century. From memory, I think that it was estimated that 8% of colonies
were infected with AFB prior to the introduction of official controls on
the early 1940s - a policy of compulsory destruction of all AFB infected
colonies and no antibiotic use.  Since then AFB has been a diminishing
problem in the UK. Currently it is found in around 0.5% of colonies
inspected. Probably the actual incidence is somewhat lower.

James

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___________________________________________________________________________
James Morton
South-Eastern Regional Bee Inspector
Central Science Laboratory
National Bee Unit
CSL website: http://www.csl.gov.uk
National Bee Unit website: http://www.csl.gov.uk/prodserv/cons/bee/