Wasps and Anaphylaxis

Wasps have their uses (believe it or not). They can be of use around the gardens of our commercial and domestic premises as consumers of flies and dead insects. In as far as they relate to us, however, they can be a real nuisance. Aside of the pain caused by the stinging, their persistent nature can be a real irritation and threat to those individuals who have the misfortune to be allergic to their sting. If you are stung in the neck or in the mouth, or, indeed, if you experience nausea, giddiness, unusual swelling or extreme pain following being stung you must immediately seek medical assistance.

We are all aware, especially those of you who have been paying attention to the Key West blog, that wasps can sting multiple times without dying. Did you know, however, that the venom in wasps contains a pheromone the makes other wasps more aggressive? Bear this in mind if you are tempted to swat a wasp within close proximity of other wasps, or its nest. In other words: don’t do it.

For the majority of people a wasp sting should wear off within 24 hours. For a small minority the venom in wasp stings causes anaphylactic shock. This can be fatal.

What can cause anaphylactic shock?

Certain foods will cause anaphylactic shock in some people. These include: peanuts, almonds, walnuts, cashews, Brazil nuts, sesame, fish, shellfish, eggs and dairy products.

Other non-food causes include: natural latex (rubber), penicillin and other drugs and injections, and the stings of bees and wasps.

For some people, physical exercise can trigger an anaphylactic reaction, in some cases simply by itself; in other cases when it is done in conjunction with another cause such as foods or drugs such as aspirin.

The symptoms of a severe allergic reaction include the following:

1 (1) A sense of impending doom

2(2) Swelling of the throat and mouth

3(3) Alterations in heart rate

4(3) Flushing of the skin generally over the body

5(4) Hives anywhere on the body (this is similar in appearance to nettle rash)

6(5) Difficulty in speaking and swallowing

7(5) A sharp decrease in blood pressure (in this case the patient would experience a sudden feeling of    weakness)

8(6)  Severe asthma

9(7) Abdominal pain 

  (8) Nausea and vomiting

1(9) Collapsing and unconsciousness

Not all symptoms might be present in the same episode of anaphylaxis.

Anaphylaxis occurs, as with any allergic reaction (although anaphylaxis is the most extreme), because the immune system reacts disproportionately in response to the presence of a substance. The body’s immune system is incorrectly perceiving such substances as a threat.

The symptoms of anaphylaxis are the result of a sudden release of chemical substances, which include histamine, from cells found in the blood and stored within tissues. Such a release is engendered by an interaction between the allergic antibody Immunoglobin and the falsely offending substance (allergen), which includes wasp venom. This immunising defence is very sensitive and even extremely small quantities of the allergen can cause a reaction. When the reaction has been triggered by an allergen the released chemicals act on the blood vessels, causing swelling. For people with asthma, the reaction is mainly located in the lungs. A fall in blood pressure may be experienced.

For people who are known to experience a severe reaction, adrenaline auto-injectors are prescribed. Adrenaline, or epinephrine, acts swiftly to constrict blood vessels and relax smooth muscles in the lungs to help improve breathing. The adrenaline will also help stimulate the heartbeat and help to stop swelling around the face and lips.

Who is at risk from anaphylaxis?

If an individual has experienced a serious allergic reaction in the past, then no matter what the cause was, future reactions are probably going to be severe. If a tiny dose of an offending substance causes a significant reaction, or if a reaction has occurred between such a substance when in contact with the skin, this is an indication that a larger dose might well trigger a severe reaction. If an individual has asthma or other allergies it is important that they see an allergy specialist – asthma puts an individual in a higher risk category. If you believe that you have an allergy, see your GP. If there is a chance that your allergy is severe, the GP should refer you to an allergy clinic.

Bear all of this in mind when you are dealing with wasps. The main points to take away are: (1) if you swat a wasp near other wasps, others will follow (don’t do it); (2) if you have experienced bad allergic reactions in the past, you may be vulnerable to wasp stings and might react with anaphylactic shock; (3) anaphylactic shock can be fatal; (4) if you suspect you have an allergy, see you GP.