DIAGNOSING BEE DISEASES IN THE APIABY 27 



ACARINE DISEASE 

 CAUSE 



Acarine disease of adult honej^bees is caused by a very small mite, 

 Acarapis woodi Remiie. This mite lives as a parasite in the anterior 

 thoracic tracheae (breathing organs), where it feeds directly upon 

 the tissues of the bees. Bees are not noticeably injured by one or a 

 few mites, but the mites breed and multiply within the trachea until 

 they become very numerous. Heavily infested bees are unable to fly 

 and soon die. 



DISTRIBUTION ^ 



This disease of adult bees is not present in North America, but 

 serious losses occur from it in Europe. Queens imported from 

 Europe are sent directly upon arrival in the United States to the 

 Government Bee Culture Laboratory at Washington. The attendant 

 bees are examined for mites and other bee diseases. The imported 



?ueens are placed in new cages with young worker bees from the 

 rovernment apiary before they are sent to the beekeeper who pur- 

 chased them, in accordance with an act of Congress of 1922.^ The 

 rules and regulations and special rules incident to this act can be 

 obtained by writing to the Bee Culture Laboratory, Bureau of En- 

 tomology and Plant Quarantine, National Agricultural Research 

 Center, Beltsville, Md. 



TRANSMISSION 



The mites enter the tracheae at their openings (spiracles). When 

 a few bees, or even one, of a colony become infested with fertile 

 female mites, acarine disease may be transmitted to other bees within 

 the colony. The mites mate within the tracheae, and later some of the 

 females crawl out and enter the tracheae of other bees within the 

 hive, thereby transmitting the disease. Acarine disease is thought 

 to be transmitted from diseased to healthy colonies by the drifting 

 of infested workers, or drones, or by robber bees. This disease may 

 also be transmitted by requeening a colony with an infested queen. 



SYMPTOMS 



Infested bees are unable to breathe normally, and the walls of the 

 tracheae and other tissues are injured. Bees that contain large 

 numbers of mites are unable to fly and are known as crawlers. 

 Crawlers usually leave the hive, when the weather is favorable, and 



iThe act of Aug. 31, 1922 (Public, No. 293 — 67th Cong.), entitled "An Act To regulate 

 foreign commerce in the importation into the United States of the adult honeybee (Apis 

 mellifica)," provides as follows : 



"• * • That, in order to prevent the introduction and spread of diseases dangerous 

 to the adult honeybee, the importation into the United States of the honeybee (Apis melli- 

 fica) in its adult stage is hereby prohibited, and all adult honeybees offered for import into 

 the United States shall be destroyed if not immediately exported : Provided, That such 

 adult honeybees may be imported into the United States for experimental or scientific 

 purposes by the United States Department of Agriculture : And provided further. That 

 such adult honeybees may be imported into the United States from countries in which the 

 Secretary of Agriculture shall determine that no diseases dangerous to adult honeybees 

 exist, under rules and regulations prescribed by the Secretary of the Treasury and the Sec- 

 retary of Agriculture. 



"Sec. 2. That any person who shall violate any of the provisions of this Act shall be 

 deemed guilty of a misdemeanor and shall, upon conviction thereof, be punished by a line 

 not exceeding S500 or by imprisonment not exceeding one year, or both such fine and Im- 

 prisonment in the discretion of the court." 



