Colony collapse disorder (CCD) is a phenomenon caused by a variety of different causes. The list begins with parasitic diseases varroosis and nosemosis, which are the most widespread diseases among bees. They are followed by honeybee viruses such as the Israeli acute paralysis virus (IAPV) and the deformed wings virus (DWV). Both viruses can be carried by the varroa mite.
Next, we have climate change. To be more specific, two major weather changes are linked to bees. Drought stops flowers from producing nectar and pollen, so the bees are left without food. Also, winters are getting shorter. This is why bees work about one month more now, which means more stress for them. Other important factors are pesticides such as neonicotinoids, as well as electromagnetic fields and migratory beekeeping. This last one is very popular in America, where farmers need to pollinate trees and crops.
CCD is a very complex matter. It is difficult finding solutions that can solve it all in one blow.
News from the scientific community
Scientists identified a series of genes that could give bees more chances of survival.
The 15th February 2019 a team with more than ten biologists from York University carried out a study published on the journal Genome Biology and Evolution. They found the genes responsible for hygiene-related behaviours. Such genes might be used to enhance disease-resistant traits.
More specifically, the study describes how bees have two different kinds of immunity. The first one is the immune system, which is comprised of proteins that detect pathogens and start a series of reactions that aim to reduce or eliminate the threat. The second one is the social immunity, which is constituted by a series of prophylactic procedures.
Scientists include in this second category producing secretions that limit growth of bacteria and fungi, excluding of other bees as well as self-excluding from all or part of the colony, removing or cannibalising infected or deceased workers, grooming and removing dead or infected larvae. These responses prevent epizootics very effectively.
The findings in this study pave the way for new lines of scientific inquiry. This will let scientists take a break from field work and do more research inside the lab. Bee-genomics expert Amro Zayed foresees how fruitful working in this direction may be. More research could lead to generating healthy disease-resistant colonies, but most importantly, enhancing bees’ social immunity. This last trait will play a major role for beekeepers who will try selective breeding.