Reactions to bee stings

Since humans react to any sting in one of four ways it is possible to make sense of what is happening.

or skip the science - click to Anaphylaxis

The Aetiology of Allergy (extremely simplified)

Immunoglobulin E, histamine release. prevention of anaphylaxis

Normal Inflammation

The effect of venom is a consequence of its direct local toxic effect and your body’s inflammatory response. The response is orchestrated by chemicals, including immunoglobulins (IgG and IgM), that are produced by the lymphatic system (eg lymph glands). With inflammation, small blood vessels become leaky so that red blood and white blood cells enter the bodily tissues and the area becomes red, warm and swollen. This is how your body starts the healing process.

Different immunoglobulin: IgE helps the body fight parasites like liver flukes, and to mount a rapid response against things like pollen. It does so by stimulating histamine release from mast cells. Mast cells are present in the lining of organs, blood vessels and skin.

Allergy

IgE It is normally present in blood in minimal amounts. However, if your body is repetitively exposed to foreign substances (like pollen or bee venom) the levels can rise. Massive IgE binding to mast cells causes release of a humungous amount of histamine, and this causes anaphylaxis. In reality, it is not so simple. Other chemicals are involved but histamine is pre-eminent.

Prevention of allergy

Beekeepers who receive more than 200 stings annually have undetectable venom specific IgE (VSIE), they have specific IgG and do not respond to bee venom skin pricks (that emulate a bee sting). Beekeepers with fewer stings typically have detectable VSIE, no IgG and are more likely to respond to a skin prick.

It is clear that many stings cause desensitisation. People who are stung less frequently are more likely to suffer anaphylaxis per sting than those who have a lot.

Whilst getting stung is not a sign of a good beekeeper and in the short term getting more stings will increase your risk of anaphylaxis, in the long term, 200 stings every year will reduce it (50 stings being insufficient to bring reliable benefit). If you no longer react to stings, except for a little itch, you may be well on the way to never suffering anaphylaxis. Please note that I am not advocating that you get stung more frequently, just what would happen if you did.

A person’s propensity to anaphylaxis is to some extent genetically determined, which presumably results in no two cases of anaphylaxis being quite the same.

Types of allergic reaction

Local

A sting results in local swelling, a small patch of redness, swelling, soreness and irritation. The amount of swelling depends on where you are stung, being worse in situations where there is little “flesh” at the site, like around your eyes. This is a response to venom.

Large local

This is when the swelling around the sting site exceeds 10 cm. The swelling extends further than the sting and lasts several days. If your arm swells up, that isn’t so bad, but if the sting is on your lip it could be life-threatening. A large localised reaction does not progress to anaphylaxis. It is a large reaction to venom.

Severe allergy

A severe response is characterised by flushing or a rash that can be subtle or dramatic. It may be patchy, or widespread. It is often itchy. The weals may be pale, pink, or red, and may look and feel like hives / nettle stings. Frequently they are of variable shapes and sizes, and surrounded by a red flare. Mild swelling may occur, most commonly of the face, throat, hands, or genitalia. It is due to an allergic reaction with histamine release. It is sometimes referred to as sub-anaphylaxis. There is an absence of ABC symptoms (as described below). Occasionally, the rash progresses to anaphylaxis, contrapose, 10–20% of people with anaphylaxis never get a rash.