The idea that varroa is not a problem for the majority of beekeepers is false. Some claim that it is not a problem, but self-reporting is unreliable at best. These data reflect the actual picture in the USA

> Varroa mite prevalence for 2011 is similar to that observed in 2010 (92.4%) and 2009 (87.1%) and indicates that almost 91.8% of all 781 alcohol samples had at least one Varroa mite. While prevalence did not change over the tree years of survey, the overall mite load in infested apiaries has increased steadily since 2009. 

> While the economic threshold for Varroa mites is seasonally and regionally specific, generally an average load of over 3 mites per 100 bees is of concern. Worryingly in 2011, 62.9% of the samples that tested positive for Varroa (450 out of 716) exceeded the lower threshold for possible damage to a colony from Varroa. ... 100% of the samples received in May 2012 had Varroa mites.

> The survey in 2009 reported the highest incidence of IAPV but 2010 saw the highest incidence of DWV and ABPV. In this survey year, DWV and BQCV, the two most ubiquitous viruses among honey bees, were detected in every state sampled.

> The most prevalent pesticides include Coumaphos and its metabolites (detected in 39.4% of the samples), Fluvalinate (detected in 38.4% of the samples), Thymol, and 2, 4 Dimethylphenyl (a metabolite of Amitraz), both detected in 27.3% of the samples and Chlorpyrifos (detected in 20.2% of the samples).

> Varroa mite loads were seen to increase over the 3 years of the survey and it is unknown what this cause may be but possible explanations include fewer beekeepers treating, mites becoming resistant to available treatments or an improved snapshot of the actual mite infestation across the country.

> 2011-2012 National Honey Bee Pests and Diseases Survey Report.  KAREN RENNICH, et al

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