## 4 Discussion
sculpturalis_ highlighted additional concerns, particularly regarding the interactions between native and exotic species, which may facilitate the cross-exchange of pathogens and exacerbate the existing challenges in pollinator health. We recorded significant differences in the overall presence of honeybee viruses between the two years and, certainly, our monitoring schedule partly justified this result. Our aim was to intercept the highest viral load for the majority of viruses, achieved by the 2020 records that perfectly aligned with the existing literature [81; 82; 83]. The extended monitoring in the second year likely captured a more comprehensive picture of viral prevalence across the different phases of the colony's life cycle. However, variability between the years can also be dependent upon fluctuating environmental conditions, colony health, and stressors that significantly impact viral dynamics in honeybee populations [83]. It has been previously shown that multiple RNA viruses associated with honeybees are frequently present in sympatric wild bumblebee populations [84] and that viruses initially thought to be specific to honeybees are much more widespread. Therefore, RNA virus transmission between the managed and wild bees should be considered a common phenomenon [85]. However, the directionality of virus transmission remains elusive in most cases [20]. Regardless of the origin and directionality of viral transmission and given the type and frequency of interactions observed (i.e., many interactions concentrated on a few floral taxa and thus convergence of many pollinator species on shared plant resources), it is highly probable that the conditions for an indirect transmission of pathogens via the fecal-oral route have been fulfilled. Concurrently, identifying individuals with elevated viral loads provided insights into the potential role of these individuals as 'eliminators' responsible for active contamination. Conversely, individuals with low or medium-low viral loads may indicate a 'latent' infection or passive contamination. Notably, viral loads exhibited substantial variation at the individual level and within population-level prevalence. The variation in viral load and prevalence among individuals within a population is a key finding of this study. Our data from comparing the two sampling years revealed that BPV was always the pathogen with the highest prevalence. The virus was identified in honeybees, _An. florentinum_ and both _B. terrestris_ and _B. pascuorum_ in 2020, and again in _A. mellifera_, _An. florentinum_, and _B. terrestris_, as well as in _O. cornuta_ and _M. sculpturalis_ in 2021. BPV was one of the first honeybee viruses proven to be transmissible to bumblebees [86]. Its pathogenic capacity was found to be evident in the presence of a varroa mite infestation [87], and it has therefore been associated as a co-factor in colony loss associated with varroa mites. In the study of [85], ABPV was found to be more prevalent in bumblebees than in honeybee foragers, and indeed, bumblebees were harboring a wide range of pathogen loads, including a substantial proportion of putatively high infections (>109 virus particles per individual). ABPV is a member of a complex of three closely related viruses, including the Kashmir Bee Virus (KBV) and the Israeli Acute Paralysis Virus (IAPV), which are collectively named the AKIcomplex [88]. The AKI complex of viruses has a broader host range, being detected and found to be actively replicating in different _Bombus_ species [42; 89] and thus impairing their fitness [24]. Furthermore, IAPV was detected in bumblebees, and there was evidence that its infection was spread from the infected honeybee colonies to the non-_Apis_ hypmenopteran pollinators [42]. Additionally, the AKI complex was detected in five other wild bee genera, including species within the Halictidae family [33]. Interestingly, our study did not detect the presence of both KBV and IAPV. DWV, one of the most prominent honeybee viruses, was identified as being exclusively associated with _A.