Yellow Jacket Stings


Why They Sting

Stinging insects such as bees, wasps, yellow jackets and hornets use their stings to subdue prey (primarily insects and spiders) and to defend themselves or their colony. While various species display different degrees of aggressiveness, the same basic reasons for attacking and stinging are the instinctive desire to feed themselves or their colony members and to protect and defend their colony.

General Appearance and Nest Location

Yellow jacket workers are about ½ inch long, typically have yellow and black stripes, while some species are also marked with red. These stinging insects have far fewer body hairs than honey bees and there is a noticeable narrowed segment between the yellow jacket’s thorax and abdomen (thread-waist). Yellow jackets build their nests with a paper-maché material, their nests are usually located underground, but can sometimes be found in sheltered above-ground sites such as wall voids of buildings, cracks in masonry work or woodpiles.

Categories of Sting Reactions and Symptoms

Typical symptoms and reactions to stings by yellowjackets do not differ to a large extent except when a victim is stung multiple times by many individual insects and the victim is highly allergic to the insect’s venom. Generally, stings produce the following reactions and symptoms:

  1. Localized reactions. These are the most common types of reaction to a bee or wasp sting. Symptoms include pain, swelling, warmth, redness at the site of the sting and itching. These symptoms arise soon after stings and take several hours to subside. Large localized reactions may result in pronounced swelling, as well as fatigue and nausea, and take a week to clear up. These symptoms do not cause major medical problems and are usually limited to or are very near the sting site.
  2. Secondary bacterial infections. This type of skin infection develops if the sting site is frequently scratched and bacteria are given a suitable condition in which to develop. Failure to adequately clean, disinfect and medicate sting sites enable infections to occur.
  3. Systemic (affecting the whole body) allergic reactions. These reactions occur in people or pets that have produced a type of antibody, known as immunoglobulin E, against the same insect venom from a previous sting. Systemic allergic reactions are critical medical issues, but occur in a very small percentage of stings. Symptoms of systemic allergic reactions include swollen red bumps on the skin, flushing of the skin and difficulty breathing due to swelling of the pharynx epiglottis and narrowing of the bronchial passages. The reactions may vary in severity from mild skin to life-threatening. Anaphylaxis, the most severe immunologic reactions, occur more commonly in males and people less than 20 years of age. In severe reactions, hypotension (low blood pressure, circulatory disturbances, and breathing difficulty) can progress to fatal cardiorespiratory arrest. Most people who develop anaphylactic reactions have experienced previous stings with few problems, but once an individual has experienced an anaphylactic reaction, the risk of having a recurrent episode is above 50 percent.

Toxic reactions result from toxins in venom rather than the immune response elicited by the body. In most cases, toxic reactions are the result of multiple stings, which insert a remarkably large quantity of venom into the body.

  1. Symptoms can include fever, nausea, vomiting, diarrhea, headache, fainting and convulsions. Swollen red bumps, rash and other skin-related symptoms are less common in toxic reactions than in systemic allergic reactions. Because stinging insect venom is a strong stimulant that causes the immune response, people who have experienced toxic reactions may produce antibodies to the venom and be at risk for future systemic anaphylactic reactions to stings.
  2. Delayed reactions occur, but are uncommon and may show up days to weeks after the sting. These reactions constitute less than 1 percent of all reactions to insect stings. Delayed reaction symptoms can vary a great deal and may include inflammation of the brain (encephalitis), the nerves (neuritis), blood vessels and kidneys as well as blood clotting disturbances.