Resistant varroa mites in the UK

The eventual emergence of pyrethroid-resistant varroa mites in the UK was
inevitable; which is why we at Vita have been promoting product rotation and
IPM systems in beekeeping for many years. How the resistance was caused is
really academic but that does not mean legitimate product labels should not
be adhered to. These documents after all are derived through years of trials
and final approval by the country authorities.

Here in the UK two closely-related varroacide treatments are approved [by
the Veterinary Medicines Directorate], Apistan and Bayvarol. Where there is
resistance to pyrethroids, the efficacy of both products will be

Besides Apistan, Vita is researching into several new treatments for
honeybee health. Our thymol gel product Apiguard is undergoing pan-European
registration at present (as well as in other continents). It is unusual in
already being available to beekeepers in the UK under the label of a
"non-medicinal curative substance" but should be a veterinary medicine here
as in most of the EU by early 2002).

We developed this product with beekeepers, bee institutes and Universities
in mainland Europe - trials notably in Italy, France and Germany in
pyrethroid-resistant mite areas. Apiguard works very well against varroa
mite as well as other pests. Average efficacy is 95%, higher in warmer
climes, sometimes lower in colder areas. Even with our specially developed
slow-release gel system there is some temperature dependence but we believe
that this can be overcome in cooler areas by extending the treatment period
slightly and by spreading the gel out. Noone is claiming that by using
Apiguard 99% of mites are going to be controlled every time - sometimes
maybe but probably not every time. Thymol works in a completely different
way to pyrethroids, so unlike with some other substances, such as
organophosphates there is little risk of cross-resistance occuring. Apiguard
treatment will control pyrethroid-resistant mites.

In the UK summer seems to pass us by so quickly. When the sun appears in a
blue sky for more than three hours at a time, the use of hose pipes is
immediately banned and women and young children start fainting in the street
with heat exhaustion.
Despite the British weather, Apiguard has been used pretty successfully by
many beekeepers even here. It may not be the perfect solution but with some
modification to treatment duration and method it should serve as a useful
tool, as an alternative to or in rotation with other treatment methods. And
it is legal!

We are working on other natural control agents for varroa (including a
pheromone blend; NB this will unfortunately not be ready for at least
another 18 months) as well as natural agents for the control of foulbroods
and chalkbrood. Any profit made goes back into R&D for new products for
honeybee health.

Yes, there are the first signs of pyrethroid-resistant varroa in the UK but
if beekeepers start doing something about it now - ie by using a multiple
attack and/or product rotation system the resistant mites can be limited and
it will prolong the lifespan of all existing and future treatment regimes.
This is no time for thunder clouds of despair and doom, there is much to be
positive about, providing beekeepers will accept Integrated Pest Management
principles and use additional or rather alternative tools.

Dr Max Watkins
Vita (Europe) Limited
21/23 Wote Street
Basingstoke, Hants RG21 7NE UK

Tel. +44 (0) 1256 473177
Fax +44 (0) 1256 473179