Do high mite numbers increase the risk of nosema in a bee colony?

High mite numbers do indeed increase the risk of Nosema infections in bee colonies. Varroa mites weaken honey bee colonies primarily by feeding on their blood, which disrupts their immune systems and overall health. When bees are infested with a significant number of Varroa mites, their stress levels increase, making them more susceptible to various pathogens, including Nosema, a microsporidian parasite that affects the digestive system of bees.

Healthy bees with a strong immune response can manage and overcome some level of pathogen exposure, but when combined with the stress and damage caused by mite infestations, their ability to combat Nosema declines. This compromised health can lead to a higher prevalence of Nosema disease within the colony, further contributing to declines in bee population and productivity. Thus, the relationship between high mite numbers and increased risk of Nosema is well-documented in beekeeping science.