Diseases & Pests of Apis Mellifera

Parasitic Mite Syndrome (PMS)

Bee Parasitic Mite Syndrome (BPMS)

Bee Parasitic Mite Syndrome was first named by The Beltsville Bee Lab to explain why colonies infested with both varroa mites and tracheal mites were not thriving. BPMS was first reported by European beekeepers whose colonies were already stressed by varroa mites. Colonies that are apparently very healthy and productive suddenly experience a sudden decrease in adult population often resulting in the total loss of the colony. Plenty of food stores are often present, but very spotty and unhealthy brood are observed. This phenomenon can occur at any time during the bee year, but is most often experienced in the autumn. To prevent the typical autumn die-off associated with BPMS, it is critical to control the varroa mite infestations earlier in the beekeeping year. In a survey conducted at Beltsville Bee Lab, it was reported that 28% of the colonies diagnosed with BPMS contained both varroa mites and tracheal mites. However, it is believed that varroa mites are the principle mite species associated with syndrome. No specific pathogen has yet been identified. BPMS mimics other diseases. It may be connected with the vectoring of one or more viruses by both mites, such as acute bee paralysis virus or Kashmir virus. It has been shown that varroa mites transmit viruses that can be more devastating than their own feeding activities.

Symptoms of BPMS found in brood:

1. Varroa mites are present.

2. Tracheal mites may be present.

3. Spotty brood pattern. (one reason may be that hygienic bees removed the cappings and removed the dead larva)

4. Dead brood may been seen anywhere on the comb, in all stages of development, with a mixture of symptoms present that may suggest one of several diseases depending which individual larva is inspected. (AFB, EFB, sac brood)

a. Typical of EFB: young dead brood appear twisted and brownish in color and look deflated

b. Typical of AFB: older dead brood not ropey, but may have scale that is not brittle and is easier to remove than typical AFB scale.

c. BPMS specific: Dead larvae that were originally a dull white color may eventually develop gray or brownish spots.

5. Dead brood lacks the distinctive odors of either AFB or EFB.

Symptoms of BPMS found in adult bees:

1. Varroa mites are present.

2. Tracheal mites may or may not be present.

3. Reduction in adult population.

4. Queen superseded more than normal.

5. Crawling, unhealthy adult bees with deformed wings in hive and at the entrance.(Deformed Wing Virus)

6. No predominant disease bacteria present.

The following treatments have been effective:

1. Feed colonies with Terramycin® in 1:1 sugar syrup.

2. Feed colonies with fumagillin.

3. Feed colonies pollen substitutes.

4. Treat for tracheal mites with vegetable oil patties.

5. Treat colonies with Apistan Strips®.

6. Use resistant bee stock (e.g. Buckfast, Hygienic)

7. Breed queens from colonies that appear to have some resistance to mites.

One confusing issue is that feeding Terramycin® in sugar syrup is not known to be an effective treatment against viruses, nor is it the industry approved method of dispensing Terramycin®. Further research does show that Terramycin® in sugar syrup is a much more effective method to feed the bees, but only in small one-day dosage size amounts. After one day the effectiveness of the medication in solution is seriously degraded and of much less benefit than the more traditional powdered sugar feeding method. However, in this case, it assists in making symptoms disappear, as does the use of Apistan Strips® (fluvalinate).

Integrated Pest Management (IPM) will definitely be a key to defeating this disease.

Not a lot has been published concerning BPMS up to date, but for a layman’s non-academic synopsis I recommend Dr. Caron’s book Honey Bee Biology and Beekeeping, chapter 20 Box 45. It is written in a style that is easy for the hobby beekeeper to read and understand.

Primary Reference:

Caron, Dewey M. 1999. Honey Bee Biology and Beekeeping. Wicwas Press Cheshire, CT

References:

Delaplane, Keith S. 1996. Honey Bees & Beekeeping A Year In The Life Of An Apiary. University of Georgia Cooperative Extension Service

Collison, Clarence. 2003 What Do You Know? The A. I. Root Co. Medina, OH

Sammataro and Avitable. 1998. The Beekeeper’s Handbook. Cornell University Press. Ithaca, NY.

Penn State College of Agricultural Sciences.1999. Honey Bee Parasites, Pests, Predators and Diseases

Information compiled by Beekeeper Lonnie E. Campbell of The Loudoun Beekeepers Association.