Treatment of bumblebee stings and allergies
1. Bumblebee and honeybee stings
Only bumblebee workers and queens have a stinger, as with honeybees and wasps. Drones cannot sting. The stinger is a weapon for defence. When a bee stings, some venom is injected into the body though the stinger. In humans, this generates a short severe pain that then fades away. Occasionally (in approximately 1%), an allergic reaction against the injected venom develops.
A bumblebee’s stinger has no barbs. This means that the bumblebee worker or queen can withdraw her stinger, and is able to sting again. A honeybee’s stinger does have barbs. When a honeybee tries to withdraw its stinger, it tears loose from the abdomen, taking the venom gland with it.
2. How to prevent bumblebee stings
First of all, it is important to be CALM when working with bumblebees. Do not wave your arms at the bumblebees, bump the hive, etc. Also, be aware that bumblebees can react aggressively to smells such as alcohol, perspiration, perfumes, scented soaps, aftershave, and so on. Moreover, rings, bracelets and watches may cause aggressive behaviour (due to the scent of oxidised material between the skin and the jewellery). Remember, prevention is better than cure!
3. Stung? Reactions and treatments
3.1. Non-allergic, local reaction
Usually a bumblebee sting leads to a non-allergic, local reaction: swelling, itchiness and redness at the site of the sting, lasting only for a couple of hours. This can occur directly after the sting, but more generally it starts after some hours. The itching may last for hours or even days. In some cases the local reaction may spread somewhat; in that case it usually takes longer for the symptoms to go away. However, this still counts as a local, non-allergic reaction.
3.1.1. Treatment of a non-allergic, local reaction
Usually medical treatment is not necessary. Some measures can be taken to minimise the local reaction, in particular if the person was stung in a sensitive location, such as near the eyes. As soon as possible after being stung, the person should take an anti-inflammatory such as aspirin or ibuprofen. Cold compresses should also be applied to the site. In addition, a number of anti-itch ointments are available, some of which contain diethyl-m-toluamide. In the rare case of a sting in the mouth or pharynx, it is strongly recommended that the patient be brought to hospital, because this can result in blocked airways. In the hospital the patient will be given corticosteroids such as prednisone and will be kept for observation.
3.2. Allergic reaction
In about 1% of the population, repeated stings (or in some cases only two or three stings) may lead to an allergic reaction, also called a general allergic reaction, a systemic allergic reaction, or an anaphylactic reaction. Because an allergic reaction involves antibodies formed during a previous exposure to an antigen, it is not possible to have an allergic reaction after the first sting. Allergic reactions usually become evident within anywhere from a few seconds to fifteen minutes after the sting.
Allergic reactions are classified in four levels, in order of increasing severity:
Level 1 - itching, redness and swelling (urticaria, hives) over the whole body
Level 2 - level 1 symptoms plus intestinal problems (vomiting, diarrhoea)
Level 3 - level 1 and/or 2 symptoms plus difficulties in breathing and/or a feeling of suffocating
Level 4 - level 1 and/or 2 and/or 3 symptoms plus heart palpitations, anaphylactic shock
3.2.1. Treating an allergic reaction
In the case of vomiting, and definitely if level 3 or 4 symptoms appear, the victim should be brought to the hospital immediately for observation and treatment! With a level 1 reaction, you may wish to wait for a while, but a period of observation in hospital is still desirable, as the reaction still can shift to a higher level after some time.
If an allergic reaction occurs, administration of a prescription-strength antihistamine (such as clemastine) is useful. The antihistamine reduces the swelling caused by the histamine in the venom. Sometimes corticosteroids are prescribed. In the case of level 3 or 4 reactions, it is necessary to administer adrenaline first. Adrenaline (which can be self-administered via an EpiPen or similar injector) stimulates the heart, constricts the blood vessels, and opens the airways. EpiPens are only available by prescription, such as if the patient has already had an allergic reaction to a bumblebee sting. An EpiPen may also be available at companies which work with bumblebees.
3.2.2. Information for doctors
Detailed information regarding medical treatment of allergic reactions is available from Koppert on request.
3.2.3. Living with a bumblebee allergy
If you have had an allergic reaction once, you will not necessarily have an allergic reaction to the next sting. If you had a level 1 or 2 reaction in particular, the chance is small. These days it is possible to take a test using purified bumblebee venom to determine whether you will have an allergic reaction the next time you are stung. It is also possible to use the purified venom for a hyposensitisation treatment. This treatment is intended to desensitise the body to bumblebee venom. If you do not wish to undergo hyposensitisation treatment, you can obtain a prescription for an EpiPen from your doctor. This is an autoinjector which you carry with you and which is used to inject epinephrine in the thigh in the case of a sting.
Tests and treatments are available at the Allergology department of Erasmus MC, Dr. Molewaterplein 40, Rotterdam, or from Dr de Groot at the Diakonessehuis location of the RdGG in Voorburg.
3.2.4. Toxic reactions
Toxic reactions only occur when the victim is stung dozens of times in a brief period. General allergic reactions can occur in the nervous or circulatory system, such as cardiac arrhythmia or difficulties with breathing. In this case as well, the victim should be taken to hospital for treatment and observation.
3.2.5. Hyperventilation
In addition to a severe, level 4 allergic reaction, hyperventilation, perhaps as a result of shock, may also cause unconsciousness. Of course in this case it is necessary to call emergency medical services immediately.
3.2.6. Increased risk
Persons that use certain medicines (beta-blockers) and pregnant women are at increased risk when allergic reactions occur after a bumblebee sting.
Literature
De Groot, H. Allergie voor insecten, Huisarts en Wetenschap 2002; 45 (7): 362-7.
De Groot, H. Allergy to bumble bees. Curr Opin Allergy Clin Immunol 2006; 6: 294-7.
Natural progression
