Hymenoptera stings: A practical guide to prevention and management

August 1, 2006

Summertime stings-which actually peak in incidence late in the season-can result in either a mild local reaction and a lesson learned, or a systemic allergic reaction with a devastating outcome. Here are strategies to help you and your patients prevent stings and their potentially devastating outcomes.

DR. KRAKOWSKI is a clinical research fellow in pediatric dermatology at the University of California, San Diego. He is also the founder and director of the Johns Hopkins School of Medicine's annual wilderness medicine course.

DR. GOLDEN is professor of allergy and immunology at Johns Hopkins Medical Institute, Baltimore.

Staff editors: JULIA RUSSELL, Managing Editor, and JOHN BARANOWSKI, Editor, Contemporary Pediatrics

The warm weather that lures children outdoors with bare arms, legs, and, sometimes, feet is also the time when insects are most active and insect populations highest. Insects are attracted to the same fruits and flowers that attract the curious child, and to that child's sweet summertime treats. A child's curiosity and naiveté may lead him to put his nose-and hands-in places that adults know by experience to avoid. He may step barefoot on a patch of clover visited by a honeybee, or may misinterpret nature's warning signs as an invitation to investigate or play. His small size and relative inability to escape his surroundings also leave him more vulnerable to a serious situation when stinging insects attack.

A child is less likely than an adult is to have a systemic reaction to a sting, or to have a repeat systemic reaction to re-stings. Not all children, however, outgrow insect sting allergy. 1-6 One study found that one in five patients who had a systemic allergic reaction to a sting as a child had a similar reaction to a sting even more than three decades later.6 This finding suggests that physicians and parents must pay close attention to preventive measures including weighing the risks and benefits of venom immunotherapy in high-risk patients.

The usual suspects

Most clinically significant reactions related to insects arise not from biting bugs but from the business end of stinging insects of the order Hymenoptera. The families Apidae (honeybees and bumblebees), Vespidae (yellow jackets, yellow hornets, white-faced hornets, paper wasps) and the formidable Formicidae (fire ants) are the major culprits in the United States.

The small, fuzzy honeybee (Apis mellifica) is not typically aggressive, but may sting a child if trapped underfoot, in the hair, or in loose clothing. It is attracted to flowers, sweat, and some sweet-smelling perfumes and syrups.

The africanized honeybee (also known as the "killer bee") first arrived in the Southwestern United States from Mexico in 1990, after traveling up from Brazil. Its nickname derives not from any greater venom potency or allergenicity, but rather from its tendency to attack in swarms after minimal provocation. Although even incidents of 50 to 100 stings are not usually fatal, 42 deaths were attributed to africanized honeybees between 1987 and 1991 in Mexico. In the United States, 13 deaths have been attributed to them by 2002.7,8

Compared with the smaller honeybee, the large, slow-moving bumblebee(Bombus spp) is fairly noisy (think, Bzzzzzzzz), and, typically, nonaggressive. Its sting accounts for only a small percentage of those to humans.

The yellow jacket (Vespula spp) is identified by the alternating black and yellow stripes on its body. It lives in fairly large colonies of at least 500 workers in ground nests or in the crevices of natural and residential structures and mainly scavenges for meat and sweet ripe fruit or fruit syrup). It becomes most aggressive during the decline of the colony's life cycle in late summer and autumn. The yellow hornet and white-faced hornet (both of them Dolichovespula spp) are closely related to the yellow jacket: Both live in colonies of at least 1,500 workers and build teardrop-shaped nests that hang from trees or bushes. Both are extremely sensitive to vibration, such as from lawn tractors and mowers and hedge trimmers. All are highly aggressive, particularly when defending the nest.

The paper wasp (Polistes spp) builds a papier-mâché-like nest in shade, often beneath eaves, gutters, or window frames. The colony is comparatively small, with 10 to 25 wasps. It is more prevalent in the Southern United States than in the Northeastern states.7