APIS Volume 5, Number 7, July, 1987
In this issue
- Bee Stings: Reactions
BEE STINGS: POSSIBLE REACTIONS
There is little that seems more threatening to many persons than being stung by venomous insects, which in most cases are classified as "bees." The misinformation concerning bee stings is legion. Many persons I talk to each year claim to be allergic to bee stings, presumably having been diagnosed as susceptible. Some carry sting kits of one nature or another prescribed by physicians. Injectable epinephrine pens, inhalants and antihistamines are also sold over the counter for this use.
Most beekeepers are used to being stung by bees, and take it in stride as a necessary part of keeping honey bees. This intimate association with bee stings often dictates that beekeepers must take on the added responsibility of being a major source of information about them. Answers can range from the most blase to sublime. The question invariably arises, how good is the advice and where does it come from. Unfortunately, the facts about bee stings are shrouded in mystery and even the medical profession continues to be embroiled in controversly over the issue.
Two kinds of reactions are usually associated with bee stings and those of other stinging insects as well: (1) local or (2) systemic, allergic or life- threatening. There is agreement that a local reaction is generally characterized by: pain, swelling, redness, itching and a wheal surrounding the wound made by the stinging apparatus. This is the reaction of the vast majority of persons and those suffering it are considered to be at little risk of death, unless the mouth or throat is affected so that the respiratory tract is obstructed. Nevertheless, many in the general population continue to believe that because they "swell up," they are at risk of losing their life when stung by bees. Ironically, it may in fact be the reverse. Those far more at risk may show no reactions to stings at all.
For the beekeeping community, an authoritative review was published 1982 by Harry R. C. Riches, "Hypersensitivity to Bee Venom," Bee World, Vol. 63, Number 1, pp. 7-72. Dr. Riches classified been venom hypersensitivity into two categories. Type I is the most usual reaction resulting from venom components affecting mast cells which then release histamine (associated with pain and swelling) and other chemicals. Type III reacions are delayed responses to stings, produced by a substance called precipitin. They are considered extremely rare.
Dr. Riches' Type I bee venom hypersensitivity reactions were listed in increasing order of severity as large local reactions, systemic reactions and anaphylaxis. Systemic reactions, he said, were generalized reactions occurring within a few minutes of a sting. Mildest symptoms were flushing of the skin, followed by an itchy nettle-rash and more serious included chest wheeze, nausea, vomiting, abdominal pains, palpitations and faintness. In addition, the speed of onset of reactions was an indication of its seriousness. Anaphylaxis, he said, occurred within seconds or minutes of a sting. Common initial symptoms are chest wheeze, nausea, vomiting and confusion followed by falling blood presure leading to death.
According to Dr. Riches, treatment of local reactions included removing the stinging apparatus and applying calamine or cold compresses (not substances containing antihistamines which can cause skin irritation). Stings inside the mouth and on the eyeball require special attention and are so very serious, he concluded, that a veil should always be worn when working bees. For treatment of systemic reactions Dr. Riches recommended adrenaline administered according to severity of symptoms by inhalation to injection by syringe, and for anaphylaxis adrenaline injected intramuscularly.
Type III bee venom hypersensitivity reactions were grouped as arthus type, serum sickness and others. Arthus reaction becomes apparent 8-12 hours after a sting and could persist two to three days. It is associated with an excess of percipitins and often causes tissue damage, blistering and bruising. Serum sickness is more likely after an episode of multiple stings (malaise, fever, joint pains, skin rashes, swelling of lymph glands, kidney disturbances) and may develop three to ten days after a sting. Finally, very rare medical disorders such as encephalitis, polyneuritis and renal failure have followed insect stings.
The latter appears to be a major symptom of mass bee attacks in Latin America by Africanized honey bees. This, however, is something totally different than incidents where one or a few bees are involved. Any person regardless of sensitivity to bee venom receiving an enormous number of stings might be susceptible to renal failure or other severe symptoms simply because their body was challenged by a great quantity of toxin.
A quick glance at Dr. Riches' categories and symptoms indicates a good deal of overlap between symptoms and treatment of systemic and anaphylactic reactions. In addition, the general tone of Dr. Riches' article appears to be one suggesting that most systemic reactions are life-threatening to some degree. Many physicians agree with this, some preferring to call any allergic or systemic reaction "life-threatening."
This life-threatening bias has little basis, according to Dr. Howard S. Rubenstein who published "Bee-Sting Diseases," The Lancet, February 27, 1982 pp. 496-499. Dr. Rubenstein begins with the statement: "Many of the large number of people who are stung each year by bees experience frightening systemic-reactions, but the vast majority of such reactions are not life- threatening. There is no evidence that the very few who die as a result of a bee sting come from the pool of those who once before sustained a systemic reaction. On the contrary, no reaction at all may be a more ominous predictor of a lethal outcome on a subsequent sting."
Death from bee stings comes about through a number of mechanisms, Dr. Rubenstein said, the most important of which appears to be atherosclerosis (build up of deposits in the arteries). Also, external factors affect mortality such as environmental temperature and site of the sting. Disagreement over bee-sting diseases, according to Dr. Rubenstein, is caused by four sources of confusion:
- the frightening presentation of the systemic reaction;
- misuse of the term "anaphylaxis";
- multiple causes of "bee- sting" deaths;
- lack of information about the systemic reaction.
The frightening aspect of being stung cannot be ruled out as a cause of a systemic reaction, Dr. Rubenstein said. "A patient who suddenly develops hives, shortness of breath (sometimes with bronchospasm), and giddiness or syncope (sometimes with hypotension) is terrified, as are those about him. The patient may think he is going to die, as may his family or physician. What people need to know, therefore, is that the vast majority of patients, particularly if agded under 25, will quickly recover." In addition, according to Dr. Rubenstein, patients who have these terrifying experiences need to know that there is no evidence either that they came to the brink of death of that they are at greater risk of dying from a subsequent sting than anyone else.
It is this last statement that raises a few eyebrows; conventional wisdom in the past has accepted that reactions are likely to get infinitely worse with each sting after a person suffers a systemic reaction. It is lamentable, Dr. Rubenstein said, that in bee sting cases physicians did not check vital signs before administering adrenaline; even more lamentable is that patients who die as a result of stings generally have post mortem diagnoses of atherosclerosis, not anaphylaxis. Anaphylaxis is very rare in humans, he said, and except in specific cases in which it truly applies, should be replaced by the neutral, non-prognostic, non-frightening and non-specific term "systemic reaction."
Multiple causes of bee sting deaths are the rule, rather than simply anaphylaxis, according to Dr. Rubenstein. Other potential complications besides atherosclerosis include sepsis, cerebral oedema, defibrination syndrome, haemorrhages, emboli and neuroencephalomyelitis variants. The fact that 90% of those who die after a bee sting are over 25, whereas most who sustain allergic reactions are children argues strongly against allergy. Only 12% adults in one set of necropsy findings died of anaphylaxis, 20% had severe and 42% mild atherosclerosis and about one-third had pulmonary oedema.
Fright cannot be ruled out, Dr. Rubenstein said, nor can very warm environmental temperature. As he stated: "One may readily see how (1) a hot summer day, plus (2) strenuous exercise, plus (3) coronary atherosclerosis, plus (4) a bee may add up to death, whether or not one invokes an allergic mechanism..."
Finally, there is a lack of detailed epidemiological study on systemic reactions, according to Dr. Rubenstein. Often cited studies showed that systemic reactions to bee stings were rather frequent, benign and self- limiting, with a prevalence in the U.S. of 0.4% to 0.8%. The authors of two studies of 8000 boy scouts which produced the above figures found no reason for alarm and did not call the reactions they witnessed either life- threatening or anaphylactic. Another study revealed that prevalence of sustained systemic reactions was no greater in an allergic population than the population at large, again not referring to the those experienced as life- threatening or anaphylactic, and further arguing against an allergic basis. In two more studies where where the combined number of systemic reactions reached over 700, no deaths were reported.
Given this evidence, Dr. Rubenstein found it difficult to understand the following statements:
"As many as 4 people per 1000 may have serious systemic reactions and therefore live in real fear of the sequelae of a subsequent sting."
"Fear of fatal reactions and the consequent change in life-style is more widespread because 0.4 to 0.8 percent of the U.S. population has survived a systemic reaction to a sting."
"Four out of every 1000 persons are so allergic to insect venom that a single bee sting can produce a fatal systemic reaction in their bodies within 15 minutes."
These statements, he concluded, suggest a deadly epidemic. The anxiety of the authors, he charged, has been transmitted to patients and physicians and unnecessarily terrified hundreds of thousands because they are not supported by any epidemiological study. Thus, Dr. Rubenstein concluded: "...when those at risk are unidentifiable and so few; when the experiment justifying the treatment is so seriously flawed; when the treatment itself is not without risk, has not been shown to do the job intended for it, and is very costly; then we cannot justify it."
All this appears to be good news for those who can now inform the curious that according to at least one physician, risk of fatality from a systemic or allergic reaction to bee sting is lower than previously thought. What must be emphasized, however, is that environmental factors and physical well being of the individual being stung cannot be ignored when judging who is at risk of dying from a bee sting. Nor can perceptions by the individual being stung . Panic by the person stung or those around him/her can produce a systemic reaction in itself. As my anthropology professor once said, "...it's not what is happening to people, but what they perceive as happening that really counts."
Sincerely,
Malcolm T. Sanford
Bldg 970, Box 110620
University of Florida
Gainesville, FL 32611-0620
Phone (352) 392-1801, Ext. 143 FAX: (352)-392-0190
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©1987 M.T. Sanford "All Rights Reserved
