Bee Diseases

It is the responsibility of every beekeeper to protect our honeybee - an essential pollinator of crops and wild plants. Bees are subject to certain diseases, both of the brood and of the adult and the beekeeper should be very vigilant to ensure that hygiene standards and good apiary management are maintained. There is the satisfaction of good animal husbandry knowing the bees are well fed, healthy and housed in dry hives safe from pests.

Hindering the spread of Disease:

• Never feed bees honey from another source.
• Arrange hives to reduce drifting and robbing.
• Never leave supers open or frames out for bees to clean out. If you wish to dry combs return them to their own colony.
• Routinely sterilise brood combs not in use with 80% acetic acid when the temperature exceeds 15 C.
• Do not overstock an area - be content with 2/3 hives in an area with little forage as in so doing you are lessening stress, whereas in a good area up to 10 hives may be kept on one site.
• During manipulation take care not to crush the bees, as this is one means by which nosema spores are spread as the house bees clean up the mess.
• Do not exchange frames of brood or honey between colonies unless you are sure they are disease free.
• Rear replacement queens from strong colonies, as in this way you are selecting for disease resistance.
• Know the signs of foul brood and other diseases. It is good practice to devote at least one examination each year to look at the brood for any signs of abnormality. A good time to do this is when the colony is queenless or has a virgin queen. You will have to remove the bees from each comb as you look at it by shaking over the open hive.

Sampling for Disease:

The beekeeper should send samples of bees - in the case of adult diseases, and comb - in the case of brood diseases, for disease diagnosis. This is the only reliable method of disease detection. Currently there is a five Euro fee (per sample) for this service. Cheques or postal order must be made payable to Teagasc. Send the samples to:

Mr. Pat Maloney
Bee Diagnostic Service
Teagasc
Malahide Road
Dublin 17

In order to test for adult bee diseases, a sample of 30 bees is required. The sample can be collected in a match box by partly protruding the tray, holding it nearly flat over the bees, on the crown board or at the front entrance, and drawing it back with a sweeping movement. Bees can be killed by placing them in the freezer for 24 hours before posting. Label each sample showing apiary, hive number together with your name and address. On no account should plastic containers be used as the bees decompose rapidly in these containers.

If the beekeeper suspects any of the brood diseases are present in the hives then, the full frame containing suspect brood from the hives should be sent also in a paper container. The sample should contain sealed, dead and/or discoloured brood if possible. It would assist diagnosis if the cappings were not damaged (ie squashed in the post).

To conclude, the beekeeper should keep up to date with new developments especially in the control of varroa and when necessary treat with an approved product at the proper rate and for the appropriate time.

Beekeepers should familiarise themselves with FIBKA Policy on Foul Brood Disease and FIBKA Guidelines on Varroa Destructor.

Dennis Ryan