Murdoch University Veterinary Hospital - For vets - Dermatology and Ear Clinic

Bee and wasp venom testing and desensitization

The medically important groups of Hymenoptera are the Apoidea (bees), Vespoidea (yellow jackets) and Formicidae (ants).

These insects deliver their venom by stinging their victims. Most deaths related to Hymenoptera stings are the result of immediate hypersensitivity reactions, causing anaphylaxis.

The estimated lethal dose is approximately 20 stings/kg in most mammals. Anaphylactic reactions to Hymenoptera stings are not dose dependent or related to the number of stings.


Reactions after insect stings

Four possible reactions are seen after insect stings:

  • local reactions,
  • regional reactions,
  • systemic anaphylactic responses,
  • and less commonly, delayed-type hypersensitivity.

Clinical signs of bee and wasp stings include erythema, oedema, and pain at the sting site. Occasionally, patients develop regional reactions. Onset of life-threatening, anaphylactic signs typically occur within 10 minutes of the sting.

Diagnosis of bee and wasp stings stem from a history of potential contact matched with onset of appropriate clinical signs.


Treatment

Treatment of uncomplicated envenomation consists of conservative therapy (antihistamines, ice or cool compresses, topical lidocaine, or corticosteroid lotions).

Prompt recognition and initiation of treatment is critical in successful management of anaphylactic reactions to Hymenopteran stings.

The majority of Hymenopteran stings are self-limiting events, which resolve in a few hours without treatment. Because life-threatening anaphylactic reactions can progress rapidly, all patients stung should be closely monitored and observed.

In cases where a life-threatening allergic reaction has occurred following a sting or envenomation, diagnosis by allergy testing and venom immunotherapy are strongly recommended.

In humans and veterinary medicine venom immunotherapy is an extremely effective treatment for preventing future reactions to stings.

The Skin, Allergy and Ear Clinic is experienced at both allergy testing and desensitization for bees and wasps.