Roe Valley Beekeepers Association
Worker Bees sting to protect their hive, and because of the barbed nature of the sting, deployment of the sting will result in rupture of their final abdominal segment, and eventual death of the bee. The sting mechanism is developed from the embryonic final three abdominal segments, which are held within a cavity, the sting chamber, enclosed by the final (seventh) abdominal segment. The components are three plates described by their shape (oblong, quadrate and triangular) which act as a lever system to move the sting shaft, a hollow canal with a barbed tip. The canal is formed from two lancets and a dorsally situated stylet containing a bulb from which venom is pumped as the lancet parts move. The venom sac is fed by a pair of exocrine glands, the poison or acid glands, and feeds the venom into the bulb mechanism. There is another gland (the Dufour or alkaline gland) which lubricates the mechanism. The plates are operated by muscular contractions and result in the stylets moving differentially. As the bee arches and the sting is extended, the stylets are driven into the skin and venom is pumped through the sting shaft.
Bee venom is composed of a number of chemicals the most important of which is a protein (Melitin) which caused rupture of blood and mast cells. Mast cell rupture releases Histamine in animals and humans. This is a potently vasoactive substance which causes vasodilation and initiates an inflammatory response. Other venom products include phospholipase and hyaluronidase, both of which break cell walls down, with resultant release of other animal chemicals including 5-Hydroxytriptamine , responsible for inflammation and pain.
Beekeepers exposed to stings will suffer a range of reactions. At one end of this spectrum is a mild local inflammatory reaction, producing an area of redness, swelling, pain, heat and itchiness. This is the usual reaction with which we are all familiar, and typically resolves within a day or less. These stings can be ignored or you may wish to intervene, especially if you have been stung more than once.
Removal of the venom sac by flicking it out is the first action to take, to minimise the venom dose. An ice cube placed on the stung area will cool the area down and reduce the inflammatory reaction. An anti-histamine cream could also be applied (eg Anthisan, which can be bought without prescription). If your reaction is a little more severe you may consider taking anti-histamine tablets (like Piriton) or an anti-inflammatory drug (eg Diclofenac).
At the other end of the spectrum are more severe reactions which result from hypersensitivity or allergy to the venom components, particularly the proteins. This results in an immune system cascade reaction with release of vasoactive substances. Their effects include general vasodilation, facial swelling (oedema), generalized whole-body rash, a fall in blood pressure, dizzyness, weakness, headache, central chest pain, palpitations and wheeze or difficulty in breathing. The most serious of these severe reactions is anaphylaxis, in which the victim may collapse, with a rapid fall in blood pressure, and cardio-respiratory arrest. This reaction will be fatal unless immediate medical care is administered. Individuals with a history of severe reactions may, on their next exposure, develop an anaphylactic reaction and should therefore prepare for this possibility. This preparation should include maximum precautions to avoid contact (ie giving your bees away), wearing a medic-alert warning, and carrying a supply of the necessary drugs with you. A mobile phone with speed dial would be a useful addition, as the expert help you will need will only arrive if it is called. If you have suffered any severe reaction, you should never go beekeeping alone, as reaction onset can be swift, and time is critical.
The medical treatment of anaphylaxis includes lying the victim flat, with legs elevated high (to restore some central circulation), airway support, and the administration of Adrenalin intramuscularly, intravenously or directly into the heart. Cardoiopulmonary resuscitation and oxygen delivery will also be required, and venous access will permit the administration of fluids and other drugs including Hydrocortisone and Chlorphenamine.
These responses must be initiated quickly to terminate the reaction, and to restore normal life supporting functions.
Adrenalin can be self administered using an automatic injector device, so those with previous severe reactions should have discussed this with their GP and should have their Epipen close by at all times.
However you should never rely on a single Epipen to save your life, as the dose of adrenalin required to resolve a severe reaction may be many times the Epipen dose, and additional treatments are always required. Consider it only as a life line of ten minutes duration useful until help arrives. Did you remember to phone 999?