Bee diseases

Like other organisms, the honeybee is susceptible to all kinds of diseases. Maintaining the health of bees is therefore an important aspect of beekeeping. Bees@wur works in an international framework on various bee diseases with the aim of maintaining a healthy bee population in the Netherlands.

Photo: Deformed Wing Virus infection of van bijen in the pupal stage, can lead tot deformed wings in adult bees. (Bram Cornelissen,

Honeybees are susceptible to many parasites and pathogens that can affect their health. In most bee colonies, diseases and parasites are latent, but occasionally they can resurface and cause serious damage to the health of honeybees. For example, an intestinal parasite such as Nosema spp. competes with bees for the food they have eaten. Serious infestations can lead to bee mortality.

The Varroa mite has been present in the Netherlands since 1983. This exotic pest is a major threat to bees world-wide. As a parasite, it not only reduces the life expectancy of winter bees, it also transmits viral diseases. Severe infestations can result in winter mortality of entire bee colonies. If this parasite is not controlled, there is little chance that the bee colonies will survive. Consequently, it is one of the most well-known examples of the negative consequences of exotic pests and diseases on Dutch fauna.

An important result of the research conducted by Bees@wur is the development of effective and sustainable ways to prevent and control parasites and diseases. This information is shared with beekeepers who are confronted with them. In addition, beekeepers can send samples for analysis if they are affected by bee mortality. These samples are analysed for the most prevalent parasites and diseases.

A number of parasites and diseases are notifiable. This means that legislation at the national and European level requires notification of the competent authority in case of infestation. This applies to American foulbrood disease, the exotic parasite Aethina tumida (small hive beetle) and the Asian bee mite Tropilaelaps spp.