In general, we approach beekeeping from the positive sides: techniques, beehive products, biology ... There are unfortunately also health problems of our colonies that the beekeeper may be confronted with. These are diseases and parasites. This subject is obviously less encouraging, but must be addressed.
How does the bee defend itself?
For years we keeping bees in hives. The colonies, despite some winter losses, are resisting relatively well.
When I was taking lessons, I remember a lecturer who expressed that the bee's main enemy was most often the beekeeper himself either that he had done something that was not suitable for the bees, or that he hadn't done what he should have.
Today while browsing the beekeeping forums, I have the impression that this remark is still relevant and should sometimes be repeated.
Yet the bee has an important defense capacity.
Physical defenses
The bee is covered with a hard shell called the cuticle which is actually an outer skeleton. This shell serves as a natural defense against invasions of bacteria or viruses.
Cleaning behavior
Naturally the bee exhibits a cleaning behavior adopted by an age caste. This cleaning consists of cleaning the cells and carrying out any debris encountered in the hive.
The use of propolis, an antiseptic product, to seal the openings and orifices will prevent the proliferation of bacteria and other parasites in the colony.
Delousing
This other characteristic of bees to cleanse each other also helps to bring down parasites attached to the bee's body, especially varroa. As long as the hive is equipped with a mesh drawer, these parasites are thus evacuated.
Anti-septic medium
The hive itself is also an environment that does not promote disease. Honey and propolis have anti-infectious properties which are likely to stop the proliferation of infectious agents, at least as long as they remain at an acceptable level.
Diseases:
causes
There are four causes of disease:
Bacterial diseases: American Foulbrood (AFB)
Diseases caused by viruses: black disease, sacbrood, cryptogamic diseases
Parasitic diseases: varroasis, acarapisosis, nosemosis
Diseases can attack bees or brood, and sometimes both at the same time.
Diseases
Diseases of adult bees
Acariosis
Acariosis is caused by a mite Acarapis Woodi. This pathogen lives on the bee and reproduces in the tracheae. It is able to pass from one bee to another and is therefore contagious.
Symptoms appear mostly in the spring with bees unable to fly. The disease is not transmissible to humans. There is no treatment. It is therefore necessary to eliminate the affected colonies with a sulfur wick.
Nosemosis
The disease is internal to the bee. It is caused by a protozoan that lives in the bee's intestine.
The symptom is yellow or brown diarrhea. It manifests itself especially in spring and in mild forms, it heals with the supply of fresh pollen.
Amoebiasis
This disease is caused by a protozoan in the Malpighian tubes which is the bee's excretory organ. The disease causes cysts that can block the tubes. The diarrhea is slightly sweet which favors its absorption by the bee.
We note that the disease is often present at the same time as nosemosis.
No known treatment.
Septicemia
This disease is caused by the presence of a bacillus in the hemolymph of the bee.
Bees have spread wings and are unable to fly.