■ SACBEOOD. 51 



That sacbrood is very frequently encountered; that it is infectious, 

 but that it is more benign in character than malignant; that it does 

 not spread rapidly from one colony to another; that colonies manifest 

 a strong tendency toward seK-recovery from the disease; that this 

 tendency is stronger after midsmnmer ; that the disease may so weaken 

 a colony during the early brood-rearing season that the profits from 

 it may be much reduced, or even rendered nil; and that the disease 

 may indeed destroy the colony are facts which must be considered in 

 devising logical methods for its treatment. 



That the virus of sacbrood remains virulent in larvae dead of the 

 disease for less than one month; that it remains virulent in honey 

 approximately one month; that when mixed with pollen it ceases to be 

 virulent after about one month; and that in drying no virulence is to 

 be expected after one month, are facts that apcoimt in a large measure 

 for the strong tendency to recover from the disease manifested by 

 the colony and that furnish information concerning the use of combs 

 from sacbrood colonies. From the results it may be concluded that 

 it is better, theoretically, to store combs from sacbrood colonies for 

 one or two months before they are again used, provided such storing 

 entails no particular inconvenience or financial loss to the beekeeper. 



Further experiments show that brood frames from badly-infected 

 colonies may be inserted into strong, healthy ones, and cause thereby 

 very little_infection and consequently only a slight loss. This is 

 especially true after the early brood-rearing season of the year is 

 past. Since this can be done, it is quite probable that the practical 

 beekeeper wiU find that this disposition of the combs will be the 

 preferable one to make. At any event, it is comforting to know that 

 it is never necessary to destroy the combs from sacbrood colonies on 

 account of the disease. 



The experimental results here given regarding the destruction of 

 the virus through heating, fermentation, putrefaction, drying, and 

 direct sunlight should assist materially in the solution of the problem 

 of the transmission of sacbrood, and. should be found helpful in de- 

 vising efficient methods for the treatment of the disease. 



Toward disinfecting agents it is shown that the virus of sacbrood 

 possesses, in some instances at least, marked resistance. These and 

 other experimental results thus far obtained indicate that the use 

 of any drug in the treatment of the disease should not be depended 

 upon imtil such a drug has been proved to be of value. 



No fear need be entertained in practical apiculture that the disease 

 wUlbe transmitted by thehands or clothing of the operator, by the tools 

 used about the apiary, through the medium of the wind, or by the 

 queen . It would seem at aJl times superfluous in the case of sacbrood 

 to flame or bum the inside of the hive or to treat the ground about a 

 hive containing an infected colony. 



