How to heal insect stings?

Similarity of allergic reactions to insect bites and stings

• Does an extreme allergic reaction to one type of insect bite or sting mean a higher probability of similar reactions to other insects? My 7-year old daughter is quite allergic to some mosquito bites. She was recently stung by a yellow jacket and had just a normal, mild reaction. Should we expect from this history that my daughter will not be serverely allergic to other insect stings, particularly bees? I live in the Chicago, IL area.

• Answer:

  Hello dlenef, There is no hard and fast answer to your question. Allergy to stings is an extreme immune reaction to one or more of the components present in whatever the stinging insect injects into the body. Mosquitoes do not actually have venom. They are not interested in killing off or paralysing the organism that they sting, but only in getting a good meal out of the event. “For the mosquito, the blood meal is a matter of survival for the species. These insects need blood to produce eggs. Since egg production is involved, the blood-feeding mosquito is always a female. Yes, it is the female mosquito that bites! Male mosquitoes do not bite, even though we might hear them buzzing around at times…. … Once the mosquito gets its stylets--that's what scientists call the needle-sharp parts of the mouthpart--into the skin, it injects saliva. The saliva contains chemicals that prevent the blood from clotting and is what causes the itching following the bite.” “In Mosquitoes, the Lady is a Vamp” by Tom Turpin, Extension Entomologist, Purdue University June 2003 http://www.agcom.purdue.edu/AgCom/news/archives/2003/June/030612OSLhtml.htm Your daughter has become sensitized to at least one of the anticoagulants in mosquito saliva. Since she did not react unduly to a yellow jacket sting, this means that yellow jacket venom does not contain any substances with a structure similar enough to mosquito anticoagulants to set off an allergic response in your daughter. At the time she was stung by the yellow jacket, she did not have an already developed sensitivity to any components in its venom. HOWEVER, there is always a possibility that this event could have caused her to become sensitized to yellow jacket venom. If that has been the case, then she will show an allergic reaction the next time she is stung by a yellow jacket. If she has developed sensitivity to yellow jacket venom, this might or might not mean that she will have an allergic response to stings by other types of bees and wasps. What we are looking at here is a phenomenon known as cross-reactivity. Basically, an immune response happens when structures on the surface of T and B lymphocytes (a type of white blood cell) react with a foreign substance. Whether this happens depends on the shape of the molecule. Two molecules with a similar shape can sometimes both stimulate a reaction by the same cells. In that case, they are said to be cross-reactive. So if your daughter has become sensitized to yellow jacket venom, she will also be sensitized to venom from another type of wasp or bee if it contains the same or a similar substance as the one in the yellow jacket venom. “Bees, fire ants and vespids cause insect sting allergy. These insects have unique as well as common venom allergens. Vespids, including hornets, paper wasps and yellow jackets, have common allergens. Bees and vespids have one common allergen with hyaluronidase activity; they also have unique allergens with different phospholipase activities. Fire ants and vespids have one common allergen, antigen 5 of unknown biologic activity.” “Structure and biology of stinging insect venom allergens.” by King TP, Spangfort MD., The Rockefeller University, New York, published in International Archives of Allergy and Immunology, 2000 Oct; Volume 123(no. 2) pp. 99-106. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11060481&dopt=Abstract What the above extract is saying is that vespids have similar substances in their venom, so if you are allergic to one of these insects, you will most likely be allergic to the others. On the other hand, there is only one substance that is common to bees and vespids. People who have become sensitized to this one substance will probably be allergic to both bee and wasp stings, but those sensitized to another wasp venom component will not necessarily be allergic to bee stings at all. Here is a study that looked at wasp and bee allergies in the same individuals and found that it was not possible to predict cross-reactivity from the previous history of the individual. “Double sensitization to honeybee (Apis mellifera) and wasp venom (Vespula spp.) as determined by skin test and measurement of specific IgE is common in hymenoptera sting allergy. Double-sensitized patients have either distinct antibodies for each venom or cross-reacting antibodies that recognize similar or identical epitopes in both venoms. …. we investigated 24 double-sensitized patients who were candidates for venom immunotherapy ….. Sera of 4 patients were completely cross-reacting for one venom (3 honeybee, 1 wasp), 8 patients were partially cross-reacting and 10 patients were not cross-reacting. Two patients were excluded from the study due to insufficient homologous inhibition. Data from specific IgE measurements, skin test, and clinical history were not useful for the identification of cross-reacting patients.” “Double sensitization to honeybee and wasp venom: immunotherapy with one or with both venoms? Value of FEIA inhibition for the identification of the cross-reacting ige antibodies in double-sensitized patients to honeybee and wasp venom.” by Straumann F, Bucher C, Wuthrich B. Allergy Unit, Department of Dermatology, University Hospital, Zurich, Switzerland. Published in International Archives of Allergy and Immunology, 2000 Nov; Volume123(no. 3) pp. 268-74. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11112864&dopt=Abstract There is also the question of whether someone who is allergic to anything at all is more likely to become allergic to other things. Here there does not seem to be agreement: This study says yes, that can be the case: “In a total of 525 patients with hypersensitivity reactions to hymenoptera stings diagnostic parameters of hymenoptera venom (HV) allergy (severity of reactions, skin test threshold and RAST for bee and vespid venoms) were investigated for their relationship to the following indicators of atopy: positive history of atopic diseases, elevated (less than or equal to 100 kU/l) total serum IgE and positive prick test reactions to common inhalant allergens (CIA) (grass pollen, cat epithelium, house dust mite). There was a conclusive history of atopic disease in 25%, a total serum IgE greater than or equal to 100 kU/l in 48%, and at least one positive reaction to CIA in 53%. ….. Thus, reactivity to HV in diagnostic tests is increased in the presence of certain indicators of atopy.” “Association of features of atopy and diagnostic parameters in hymenoptera venom allergy. by Przybilla B, Ring J, Grieshammer B., Dermatologische Klinik, Ludwig-Maximilians-Universitat Munchen, Germany. Published in Allergy. 1991 Nov; Volume 46(no. 8) pp 570-6. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1789397&dopt=Abstract while this one says no: The patient group in this study consisted of people with anaphylactic (whole-body) reactions to wasp stings, while the controls were people who had never shown such reactions. “The protocol included a standardized questionnaire about symptoms suggestive of atopy, i.e. medical diagnosis of asthma, perennial rhinitis or hay fever, and skin tests to common aeroallergens, i.e. house dust mites, cat danders, and grass pollens. The percentage of subjects with atopic symptoms was comparable in the two groups (32.2% for the patient group and 28.5% for the control group). Similarly, 22.6% of patients and 36.8% of controls exhibited at least one positive skin prick test. Lastly, 15.1% of patients and 18.5% of controls (a nonsignificant difference) had at least one symptom of atopy and at least one positive skin test. These findings show that atopy is not a risk factor for systemic reactions to hymenoptera stings.” “Atopy and systemic reactions to hymenoptera stings.” by Birnbaum J, Vervloet D, Charpin D., Department of Chest Diseases and Allergy, Hopital Sainte-Marguerite, Marseille, France. Allergy Proceedings, 1994 Mar-Apr; Volume 15(no. 2) pp. 49-52. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8034186&dopt=Abstract If you are at all concerned, you can ask for your daughter to be tested for sensitivity to insect stings. I hope that this answers your query to your satisfaction. Please request further clarification if required. Search strategy The starting point was my own knowledge of immunology, in which I am qualified to PhD level. I searched Google and Medline (medical journal database) for the following: 1. cross-reactivity wasp bee 2. mosquito “saliva contains” 3. atopy insect stings