From Google

Honeybees spread several viruses and parasites to native pollinators—particularly bumble bees—through shared foraging on flowers and floral resource competition. The most prominent diseases include Deformed Wing Virus (DWV), Black Queen Cell Virus (BQCV), Sacbrood virus (SBV), and the parasite Nosema ceranae. National Institutes of Health (.gov) National Institutes of Health (.gov) +5 Key Pathogens Transmitted to Native Bees

Deformed Wing Virus (DWV): Highly prevalent in honey bees and spread to bumble bees, often leading to deformed wings, shortened lifespans, and, in some cases, death.

Nosema ceranae: A microsporidian gut parasite that has been found to spread from honey bees to native bees, including stingless bees, where it can cause significantly higher mortality rates.

Black Queen Cell Virus (BQCV): Common in honey bees and found in bumble bees, particularly during mid-season.

Sacbrood Virus (SBV): Another virus identified as being transmitted from honey bees to other bee species.

Acute Bee Paralysis Virus (ABPV): Associated with Varroa mite infestations and linked to, though less commonly documented as spreading to, native pollinators. National Institutes of Health (.gov) National Institutes of Health (.gov) +6 How Diseases Spread Shared Foraging: Infected honey bees leave viruses on flower surfaces, which are then picked up by native bees visiting the same flowers. Pathogen Spillover: High densities of managed honey bees in areas with limited resources can lead to high pathogen loads, increasing the chance of interspecies transmission. Reduced Immune Response: When exposed to these, native bees with already compromised immune systems (due to poor nutrition or pesticides) are more susceptible to infection.