Fire Ants – Wasp – Bees, OH MY!
Spring in Texas brings to our minds beautiful bluebonnets and wildflowers. But spring also brings fire ants, wasp, hornets, and bees, which are not only annoying at picnics but also can be dangerous for venom allergic people. The wingless member of Hymenoptera Order is the Fire Ant, Solenopsis invicta. The Winged members are in two families, Apidae (bees) and Vespidae (hornets, wasp, and yellow jacket). Interestingly, only the female’s sting.
Fire Ants accidentally entered the US between 1918-the 1930s carried on a cargo ship from South America to a port in Mobile, Alabama. They have spread across the southeast and are further migrating.
Although they prefer warmer climates, they are migrating north following the warmer areas next to highways and roads. Also, they are mating with native ants, which has made them more cold-tolerant. Global warming will likely allow their migration even further north. They build their mounds in the warm moist soil preferring open, sunny areas, such as pastures, parks, lawns, playgrounds, golf courses and be seen in any green space such as at shopping areas or gas stations. Commonly children can inadvertently step on a mound each summer/spring.
The fire ant uses its mandible to grasp its victim, then arches its body and drives its stinger into the skin to release venom. It then pivots around its mandibles and inflicts further stings in a circular pattern.
Classically a sterile pustule form 24 hours later.
BEES, YELLOW JACKET, WASP, AND HORNETS
Flying insects in the order Hymenoptera includes bees, yellow jackets, wasps, and hornets.
Honeybees, the Apidae family, live in colonies with up to 65,000 members. They build their nests inside hollow trees or logs. When it stings, it leaves a barbed stinger attached to a venom sac in the victim’s skin, resulting in the bee’s evisceration and death. Most bee stings occur while people are walking barefoot or handling flowers. Honeybees are docile and only sting when provoked or protecting their nest. However, Africanized bees came to the US in 1990 and are a major stinging threat in southern Texas. Africanized bees are more aggressive and sting in larger numbers. Interestingly, they were brought to Brazil from Africa in 1956 to replace European honeybees with a more productive tropical climate honeybee.
Vespidae family includes yellow jackets, hornets, and wasp. Yellow Jackets cause most of the stings in this family. They build their nest underground or in human structures low to the ground and are attracted to picnic and trash containers. They are aggressive and can sting numerous times. Yellow-faced and white-faced hornets are aerial yellow jackets and build a nest in trees and shrubs. Wasp are more common in southern states and make their homes under eves and on porches and below deck railings.
TYPES OF REACTIONS-small local, large local, and systemic
Most stings cause small local reactions. Large local reactions affect 20% of kids and 10% of adults. They occur at the sting site and may extend to include the entire extremity peaking at 48-72 hours and resolve 5-10 days.
Most people will have a similar reaction to future stings. There is only a low risk of having a systemic reaction with future stings when the initial reaction was large local. Therefore, allergy testing is not needed when the reaction was limited to the area of the sting.
Systemic reactions to Hymenoptera stings are approximately 3% of adults and 1% of kids. At least 50 deaths per year occur from allergic reactions. A systemic or anaphylactic reaction occurs quickly after the sting and involves two or more organ systems. Common examples of symptoms include hives and swelling of the skin, itching and watery eyes and nose, throat itching and tightness, coughing, chest tightness, wheezing and shortness of breath, nausea and vomiting, and diarrhea sense of impending doom and cardiovascular involvement causing lightheadedness and passing out. Hives occur in at least 80% of systemic sting reactions. 60% of adults and 40% of kids with systemic reactions are likely to have another systemic reaction with future stings.
Diagnosis is made by a history of systemic symptoms after a sting and a positive skin test or blood test to Hymenoptera. Skin testing is a safely done procedure at an allergist’s office that takes a couple of hours.
TREATMENT OF IMMEDIATE REACTION
Treatment of reactions to a local area includes antihistamines, ice packs, analgesics, and topical steroids. Consider systemic steroids for a large local reaction.
Treatment of systemic reaction is quick administration of epinephrine autoinjector. Then seek medical care to monitor for a return of the symptoms. Delay in the use of epinephrine has contributed to deaths, and time delays can cause resistance to epinephrine.
AVOIDANCE OF STINGS
Avoidance includes minimizing high-risk exposure such as lawn and garden work and being near trash bins, and eating and drinking sugary items outdoors. Stings to the mouth and tongue can occur from ingesting food that is scavenged by yellow jackets. One should wear closed-toe shoes with socks and long sleeve pants and shirts. Avoid perfume and bright-colored clothing.
CAN VENOM ALLERGY BE CURED?
Patients should be able to live a normal life outside and participate in many activities such as sports and not fear an allergic reaction to an inadvertent sting. Allergy shots, immunotherapy, to Hymenoptera venom is a lifesaving procure that can cure a person of their insect allergy.