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Viruses have brought humanity many challenges: respiratory infection, cancer, neurological impairment and immunosuppression to name a few. Virology research over the last 60+ years has responded to reduce this disease burden with vaccines and antivirals.

A two-year study was conducted in Maine wild blueberry fields (Vaccinium angustifolium Aiton) on the health of migratory honey bee colonies in 2014 and 2015. In each year, three or five colonies were monitored at each of nine wild blueberry field locations during bloom (mid-May until mid-June). Colony health was measured by assessing colony strength during wild blueberry bloom. Potential factors that might affect colony health were queen failure or supersedure, pesticide residues on trapped pollen, wax comb, and bee bread, and parasites and pathogens. We found that Varroa mite and pesticide residues on trapped pollen were significant predictors of colony health measured as the rate of change in the amount of sealed brood during bloom. These two factors explained 71% of the variance in colony health over the two years. Pesticide exposure was different in each year as were pathogen prevalence and incidence. We detected high prevalence and abundance of two recently discovered pathogens and one recently discovered parasite, the trypanosome Lotmaria passim Schwartz, the Sinai virus, and the phorid fly, Apocephalus borealis Brues.

Studies on the outcomes of pesticide exposure on bumble bees have traditionally evaluated the pesticides individually. Poorly known is the effect of simultaneous exposure to multiple pesticides, which has high likelihood in agricultural landscapes. Four experiments were conducted to determine if simultaneous exposure to sub-lethal doses of the insecticide Assail® (30% acetamiprid) and the fungicide Orbit® or Tilt® (41.8% propiconazole) would cause detrimental effects on survival and colony productivity of the common eastern bumble bee, Bombus impatiens (Cresson) (Hymenoptera: Apidae). Survival of workers exposed to propiconazole was marginally reduced (Experiment 1), whereas gyne production increased in colonies exposed to acetamiprid (Experiment 2). There was a trend for fewer larvae and workers in colonies exposed to acetamiprid and a mixture of acetamiprid and propiconazole (Experiment 3). Higher wax moth infestations and densities were observed in colonies exposed to the mixture of acetamiprid and propiconazole (Experiment 4). In conclusion, exposure to the two pesticides resulted in variable outcomes in B. impatiens. Synergy between acetamiprid and propiconazole was explained as an indirect effect of enhanced wax worm infestation. We found an increased level of wax worm infestation in colonies exposed to a mixture of Assail and Tilt compared to colonies not exposed to Assail or Tilt (control) or exposed only to Assail. While this study does not provide evidence that B. impatiens are at high risk when simultaneously exposed to field rates of these two pesticides, we suggest that wild blueberry growers practice integrated pest management as a means of reducing any amount of risk to these important bumble bees.

Twenty isolates of four species of entomopathogenic hypocrealean fungi (Beauveria bassiana, Beauveria brongniartii, Isaria farinosa, and Metarhizium anisopliae) were found to be pathogenic to adults of the Asian longhorned beetle, Anoplophora glabripennis. Survival times for 50% of the beetles tested (ST50) ranged from 5.0 (M. anisopliae ARSEF 7234 and B. brongniartii ARSEF 6827) to 24.5 (I. farinosa ARSEF 8411) days. Screening studies initially included strains of B. brongniartii, which is registered as a microbial control agent in Europe, Asia and South America but not in North America. At that time, we could not confirm that this fungal species is native to North America which added uncertainty regarding future registration of this species for pest control in the USA. Therefore, subsequent bioassays documented median survival times for three M. anisopliae isolates (5-6 days to death) and two of these isolates are suggested for further development because they are already registered for pest control in the USA.