Honey bee viruses are highly prevalent but at low intensities in wild pollinators of cucurbit agroecosystems.

[Display omitted] • We quantified the prevalence and intensity of honey bee viruses in wild bees. • We tested if bee floral visitation predicts viral titers in managed and wild bees. • We detected three out of the five viruses tested in managed honey bees and wild bees. • DWV was the most common virus and had the highest titers in all bee species screened. • Floral bee visitation was not correlated with DWV intensity in bees. Managed and wild bee populations are in decline around the globe due to several biotic and abiotic stressors. Pathogenic viruses associated with the Western honey bee (Apis mellifera) have been identified as key contributors to losses of managed honey bee colonies, and are known to be transmitted to wild bee populations through shared floral resources. However, little is known about the prevalence and intensity of these viruses in wild bee populations, or how bee visitation to flowers impacts viral transmission in agroecosystems. This study surveyed honey bee, bumble bee (Bombus impatiens) and wild squash bee (Eucera (Peponapis) pruinosa) populations in Cucurbita agroecosystems across Pennsylvania (USA) for the prevalence and intensity of five honey bee viruses: acute bee paralysis virus (ABPV), deformed wing virus (DWV), Israeli acute paralysis virus (IAPV), Kashmir bee virus (KBV), and slow bee paralysis virus (SBPV). We investigated the potential role of bee visitation rate to flowers on DWV intensity among species in the pollinator community, with the expectation that increased bee visitation to flowers would increase the opportunity for transmission events between host species. We found that honey bee viruses are highly prevalent but in lower titers in wild E. pruinosa and B. impatiens than in A. mellifera populations throughout Pennsylvania (USA). DWV was detected in 88% of B. impatiens , 48% of E. pruinosa , and 95% of A. mellifera. IAPV was detected in 5% of B. impatiens and 4% of E. pruinosa , compared to 9% in A. mellifera. KBV was detected in 1% of B. impatiens and 5% of E. pruinosa , compared to 32% in A. mellifera. Our results indicate that DWV titers are not correlated with bee visitation in Cucurbita fields. The potential fitness impacts of these low viral titers detected in E. pruinosa remain to be investigated. [ABSTRACT FROM AUTHOR]