Removing Bee Stings

Conventional advice on immediate treatment of honey bee stings has emphasized that the sting should be scraped off, never pinched. The morphology of the sting suggested no basis for this, and such advice is likely to slow down removal of the sting.

Bee stings are a common, painful, and rarely deadly injury. Most literature regarding the immediate treatment of bee stings states that the sting should be scraped off, perhaps with a knife blade, credit card, or fingernail, and never plucked out by pinching with forceps or one's fingers. An examination of the structure of the bee sting made us doubt the soundness of this advice, particularly since scraping off a sting with a tool involves a delay relative to simply brushing or pinching it off. We tested the relative envenomization resulting from these two means of removing stings, and the effect of short delays in sting removal.

The sting detaches from the body of a honey bee (Apis mellifera) after stinging, in contrast to other stinging insects . It takes with it the entire distal segment of the bee's abdomen, along with a nerve ganglion, various muscles, a venom sac, and the end of the bees digestive tract. The sting itself consists of two lancets with recurved barbs on the outer aspect of their distal end, held in grooves on the stylet.

Muscular movements of the detached sting, coordinated by the attached nerve ganglion, move the stylets alternately. The barbs provide one way traction, so that the sting continues to work itself deeper into the flesh. A valve and piston on the proximal ends of the moving lancets (like an old-fashioned water pump) pumps venom from the venom sac between the stylet and the lancets, and through an opening near the tip into the wound.

To determine the amount of venom injected by a bee sting, we measured the area of the weal raised on our own forearms after stinging. In preliminary observations, the raised, relatively white weal achieved its maximum size approximately 10 minutes after stinging. Measurements were blind: the observer was unaware of the treatment being measured. Ten minutes after each sting was administered, this observer measured the maximum and minimum diameters of the raised portion of the weal, using a digital caliper.

To determine if weal size was a valid assay of envenomization, we measured the size of weals resulting from an intracutaneous injection of 5µl of water solution containing doses of 1, 3, 10, 30, or 100 µg of dried bee venom. (Bee stings contain about 150µg dry weight of venom, of which only a small fraction is typically injected).

All stings were self-administered. The area to be stung was cleaned with alcohol. We collected a worker honey bee as she flew from her hive, grasped her by her wings, and pressed her against the skin of the inside of the subject's forearm until she stung.

We marked five numbered sites on each forearm of the subject and assigned five treatments to the sites on each arm in a randomized-block design. Each treatment consisted of leaving the sting in the arm a variable number of seconds, and then scraping it out with the edge of a credit card. We employed treatments of 0.5 sec, 1 sec, 2 sec, 4 sec and 8 sec. The observer, unaware of which treatment corresponded to each site, measured the sting weal for each sting 10 min after it was administered. We collected data on 5 five-sting series on each arm of one subject .

After 2 seconds the sting was removed either by scraping it off with the edge of a credit card, or by pinching the sting between his thumb and forefinger and pulling it out. This process was then repeated on the subject's other arm, with the other treatment.

We calculated the area of the usually elliptical weals and correlated the size of the weal with the method of removal and the delay before removal. The increase in the weal area with increasing time between sting and removal reflects continuing pumping of venom into the flesh of the subject by the detached sting, and it illustrates the significance of even short delays in removing the sting.

The method of removal does not affect the quantity of venom received by the subject. This result contrasts sharply with conventional advice regarding the immediate treatment of bee stings. Probably this advice derives from a misunderstanding of the structure and function of honey bee stings. The sting continues to inject venom, but it is a valve system, not contraction or compression of the venom sac (whose wall contains no muscle) which pumps the venom.

The best defence is to AVOID BEE STINGS


Canadian Honey Home Kids & Honey Resources Contact

Removing Bee Stings Conventional advice on immediate treatment of honey bee stings has emphasized that the sting should be scraped off, never pinched. The morphology of the sting suggested no basis for this, and such advice is likely to slow down removal of the sting. Bee stings are a common, painful, and rarely deadly injury. Most literature regarding the immediate treatment of bee stings states that the sting should be scraped off, perhaps with a knife blade, credit card, or fingernail, and never plucked out by pinching with forceps or one's fingers. An examination of the structure of the bee sting made us doubt the soundness of this advice, particularly since scraping off a sting with a tool involves a delay relative to simply brushing or pinching it off. We tested the relative envenomization resulting from these two means of removing stings, and the effect of short delays in sting removal. The sting detaches from the body of a honey bee (Apis mellifera) after stinging, in contrast to other stinging insects . It takes with it the entire distal segment of the bee's abdomen, along with a nerve ganglion, various muscles, a venom sac, and the end of the bees digestive tract. The sting itself consists of two lancets with recurved barbs on the outer aspect of their distal end, held in grooves on the stylet. Muscular movements of the detached sting, coordinated by the attached nerve ganglion, move the stylets alternately. The barbs provide one way traction, so that the sting continues to work itself deeper into the flesh. A valve and piston on the proximal ends of the moving lancets (like an old-fashioned water pump) pumps venom from the venom sac between the stylet and the lancets, and through an opening near the tip into the wound. To determine the amount of venom injected by a bee sting, we measured the area of the weal raised on our own forearms after stinging. In preliminary observations, the raised, relatively white weal achieved its maximum size approximately 10 minutes after stinging. Measurements were blind: the observer was unaware of the treatment being measured. Ten minutes after each sting was administered, this observer measured the maximum and minimum diameters of the raised portion of the weal, using a digital caliper. To determine if weal size was a valid assay of envenomization, we measured the size of weals resulting from an intracutaneous injection of 5µl of water solution containing doses of 1, 3, 10, 30, or 100 µg of dried bee venom. (Bee stings contain about 150µg dry weight of venom, of which only a small fraction is typically injected). All stings were self-administered. The area to be stung was cleaned with alcohol. We collected a worker honey bee as she flew from her hive, grasped her by her wings, and pressed her against the skin of the inside of the subject's forearm until she stung. We marked five numbered sites on each forearm of the subject and assigned five treatments to the sites on each arm in a randomized-block design. Each treatment consisted of leaving the sting in the arm a variable number of seconds, and then scraping it out with the edge of a credit card. We employed treatments of 0.5 sec, 1 sec, 2 sec, 4 sec and 8 sec. The observer, unaware of which treatment corresponded to each site, measured the sting weal for each sting 10 min after it was administered. We collected data on 5 five-sting series on each arm of one subject . After 2 seconds the sting was removed either by scraping it off with the edge of a credit card, or by pinching the sting between his thumb and forefinger and pulling it out. This process was then repeated on the subject's other arm, with the other treatment. We calculated the area of the usually elliptical weals and correlated the size of the weal with the method of removal and the delay before removal. The increase in the weal area with increasing time between sting and removal reflects continuing pumping of venom into the flesh of the subject by the detached sting, and it illustrates the significance of even short delays in removing the sting. The method of removal does not affect the quantity of venom received by the subject. This result contrasts sharply with conventional advice regarding the immediate treatment of bee stings. Probably this advice derives from a misunderstanding of the structure and function of honey bee stings. The sting continues to inject venom, but it is a valve system, not contraction or compression of the venom sac (whose wall contains no muscle) which pumps the venom. The best defence is to AVOID BEE STINGS