Safety of hymenoptera venom immunotherapy: a systematic review

Anaphylactic reactions in the build-up phase of rush immunotherapy for bee venom allergy in pediatric patients: a single-center experience

Background

Anaphylaxis occurs in up to 3.5% of hymenoptera stings and can be a life-threatening emergency. Venom immunotherapy (VIT) provides excellent protection from further episodes of anaphylaxis and is well tolerated. In this study the frequency of anaphylactic reactions in pediatric patients undergoing rush bee venom immunotherapy was assessed as well as possible risk factors and modified up-dosing schemes are reported.

Methods

19 consecutive pediatric patients, who had previously experienced an anaphylactic reaction following a bee sting and showed IgE-mediated sensitization to bee venom, underwent inpatient rush immunotherapy with bee venom extract. We retrospectively compared serological findings (total IgE, serum tryptase level, sensitization to Api m1, Api m3 and Api m10 bee venom allergens) and possible risk factors between patients who experienced an anaphylactic reaction during immunotherapy and patients who did not.

Results

Three of the included 19 patients (15.8%) developed anaphylactic reactions to rush bee venom immunotherapy, all of them between administration of 40 and 80 µg of bee venom extract. However, all three patients reached the standard maintenance dose of 100 µg of bee venom following a modified VIT schedule without any further complications. Total serum IgE levels as well as Api m3 sensitization levels were significantly higher in patients showing an adverse reaction to bee VIT compared to those who did not experience any complications. There were no statistically significant differences concerning age, pre-existing conditions, type and severity of the initial reaction and Api m1, Api m10 and serum tryptase levels between the two subgroups.

Conclusion

Even if anaphylactic reactions occur during the build-up phase of VIT for bee venom in children and adolescents, venom immunotherapy can and should be continued in most cases.

Venom Immunotherapy and Aeroallergen Immunotherapy: How Do Their Outcomes Differ?

Allergen immunotherapy (AIT) and venom immunotherapy (VIT) are meant to work on the causes of allergies, respectively, to respiratory allergens and Hymenoptera venom, inducing tolerance to the allergens and modifying the natural history of allergy. Both types of immunotherapies have evidence of efficacy, but actually they present wide differences in both effectiveness and safety. Indeed, as far as the effectiveness of VIT is concerned, if the protection against fatal reactions to stings is considered as the primary objective, more than 40 years of clinical practice demonstrate complete success. The clinical success of AIT is measurable on the basis of reduction or disappearance of allergic symptoms. The difference between the two treatments is even higher as regards safety: AIT has been concerned in the past by a series of fatal reactions caused, which underwent a progressive decrease when it was understood that they were related to the presence of uncontrolled asthma. However, fatal reactions related to failure to recognize the presence of risk factors or administration errors are still reported. Similarly to what has been observed for efficacy, VIT has never been affected by fatal reactions to the administration of venom, and the most important risk of anaphylaxis, which is the concomitance of mastocytosis, is now identified by measuring its marker serum tryptase. To date, mechanisms of hypersensitivity reactions that differentiate respiratory allergy from Hymenoptera venom allergy have not been successfully demonstrated. We have examined the past and present literature in order to propose reasonable hypotheses about the mechanisms actually involved.

A Multidisciplinary Diagnostic Approach Reveals a Higher Prevalence of Indolent Systemic Mastocytosis: 15-Years' Experience of the GISM Network

Systemic mastocytosis (SM) and other adult clonal mast cell disorders (CMD) are often underestimated, and their epidemiology data are scarce. We aimed at evaluating the impact of the activity of the Interdisciplinary Group for Study of Mastocytosis (GISM) of Verona on the prevalence and incidence of CMD. We examined the data of 502 adult patients diagnosed with CMD and residing in the Veneto Region, consecutively referred to GISM between 2006 and 2020. SM was diagnosed in 431 cases, while 71 patients had cutaneous mastocytosis or other CMD. Indolent SM represented the most frequent SM variant (91.0%), mainly with the characteristics of bone marrow mastocytosis (54.8%). The prevalence of SM in the adult population of the Veneto region and of the Verona province was 10.2 and 17.2/100,000 inhabitants, respectively. The mean incidence of new SM cases in Verona was 1.09/100,000 inhabitants/year. Hymenoptera venom allergy was the main reason (50%) leading to the CMD diagnosis. Osteoporosis, often complicated by fragility fractures, was present in 35% of cases, even in young patients, especially males. Our data show a higher prevalence and incidence of SM than previously reported, confirming that reference centers with multidisciplinary approach are essential for the recognition and early diagnosis of CMD.

A Review of Honeybee Venom Allergens and Allergenicity

Honeybee venom is a source of proteins with allergenic properties which can result in in various symptoms, ranging from local reactions through to systematic life-threatening anaphylaxis, or even death. According to the World Allergy Organization (WAO), honeybee venom allergy is one of the most common causes of anaphylaxis. Among the proteins present in honeybee venom, 12 protein fractions were registered by the World Health Organization’s Allergen Nomenclature Sub-Committee (WHO/IUIS) as allergenic. Most of them are highly immunogenic glycoproteins that cross-react with IgE and, as a consequence, may give false positive results in allergy diagnosis. Allergenic fractions are different in terms of molecular weight and biological activity. Eight of these allergenic fractions have also been identified in honey. This explains frequent adverse reactions after consuming honey in people allergic to venom and sheds new light on the causes of allergic symptoms in some individuals after honey consumption. At the same time, it also indicates the possibility of using honey as a natural source of allergen in specific immunotherapy.

Bee Updated: Current Knowledge on Bee Venom and Bee Envenoming Therapy

Honey bees can be found all around the world and fulfill key pollination roles within their natural ecosystems, as well as in agriculture. Most species are typically docile, and most interactions between humans and bees are unproblematic, despite their ability to inject a complex venom into their victims as a defensive mechanism. Nevertheless, incidences of bee stings have been on the rise since the accidental release of Africanized bees to Brazil in 1956 and their subsequent spread across the Americas. These bee hybrids are more aggressive and are prone to attack, presenting a significant healthcare burden to the countries they have colonized. To date, treatment of such stings typically focuses on controlling potential allergic reactions, as no specific antivenoms against bee venom currently exist. Researchers have investigated the possibility of developing bee antivenoms, but this has been complicated by the very low immunogenicity of the key bee toxins, which fail to induce a strong antibody response in the immunized animals. However, with current cutting-edge technologies, such as phage display, alongside the rise of monoclonal antibody therapeutics, the development of a recombinant bee antivenom is achievable, and promising results towards this goal have been reported in recent years. Here, current knowledge on the venom biology of Africanized bees and current treatment options against bee envenoming are reviewed. Additionally, recent developments within next-generation bee antivenoms are presented and discussed.

Randomized controlled trial demonstrating the benefits of delta inulin adjuvanted immunotherapy in patients with bee venom allergy

Background

Allergic reactions to Hymenoptera insect stings remain a major global clinical problem. Although effective, parenteral desensitization regimens require use of costly venom extracts and require frequent visits over extended periods of time.

Objective

Adjuvants are commonly used to enhance the efficacy of infectious disease vaccines, and this study asked whether Advax (Vaxine Pty Ltd, Adelaide, Australia), a novel noninflammatory polysaccharide adjuvant, might provide similar benefits for allergy desensitization.

Methods

A randomized, controlled phase 1/2 trial was undertaken in 27 adults with a history of rapid-onset systemic allergic reactions to honeybee stings and positive specific IgE levels to evaluate the safety and efficacy of honeybee venom immunotherapy (HBVIT) combined with Advax adjuvant. Venom immunotherapy (VIT) was administered monthly for 30 months after achievement of maintenance doses.

Results

Advax-adjuvanted HBVIT was well tolerated. Around week 14 of VIT, specific IgG₄ responses peaked in both groups but increased earlier, peaked higher, and were better maintained through the end of the study in the Advax-adjuvanted arm. Several different patterns of serologic response to VIT were seen; some subjects had a dominant IgG₄ response, some had a combined IgG₄ and IgG₁ response, and some had an exclusively IgG₁ response. In some subjects specific IgE levels increased during the induction phase and then decreased, whereas in others specific IgE levels progressively decreased from the start of VIT.

Conclusion

Advax adjuvant favorably enhanced the immunogenicity of HBVIT, with an early and prolonged switch to specific IgG₄ production. The ability of Advax adjuvant to enhance VIT efficacy warrants further study.

EAACI guidelines on allergen immunotherapy: Hymenoptera venom allergy

Hymenoptera venom allergy is a potentially life-threatening allergic reaction following a honeybee, vespid, or ant sting. Systemic-allergic sting reactions have been reported in up to 7.5% of adults and up to 3.4% of children. They can be mild and restricted to the skin or moderate to severe with a risk of life-threatening anaphylaxis. Patients should carry an emergency kit containing an adrenaline autoinjector, H₁ -antihistamines, and corticosteroids depending on the severity of their previous sting reaction(s). The only treatment to prevent further systemic sting reactions is venom immunotherapy. This guideline has been prepared by the European Academy of Allergy and Clinical Immunology's (EAACI) Taskforce on Venom Immunotherapy as part of the EAACI Guidelines on Allergen Immunotherapy initiative. The guideline aims to provide evidence-based recommendations for the use of venom immunotherapy, has been informed by a formal systematic review and meta-analysis and produced using the Appraisal of Guidelines for Research and Evaluation (AGREE II) approach. The process included representation from a range of stakeholders. Venom immunotherapy is indicated in venom-allergic children and adults to prevent further moderate-to-severe systemic sting reactions. Venom immunotherapy is also recommended in adults with only generalized skin reactions as it results in significant improvements in quality of life compared to carrying an adrenaline autoinjector. This guideline aims to give practical advice on performing venom immunotherapy. Key sections cover general considerations before initiating venom immunotherapy, evidence-based clinical recommendations, risk factors for adverse events and for relapse of systemic sting reaction, and a summary of gaps in the evidence.

The use of omalizumab in allergen immunotherapy

Although omalizumab (anti-IgE) is currently only approved for the treatment of asthma and chronic idiopathic urticaria, it has also been studied as an off-label treatment for numerous allergic conditions, including use as an adjunct to allergen immunotherapy in the treatment of allergic rhinitis, asthma, venom hypersensitivity and food allergy. We conducted a review of publications involving the use of omalizumab with allergen immunotherapy, by searching PubMed with key search terms of "omalizumab" and "immunotherapy." Omalizumab has been used in combination with inhalant allergen immunotherapy for the treatment of seasonal allergic rhinitis and comorbid asthma. While there have been no randomized controlled trials evaluating the addition of omalizumab to venom IT, several case reports and small patient series have been published on the use of omalizumab with venom IT. Omalizumab has been used in conjunction with oral immunotherapy for the treatment of milk, peanut and egg, as well as other foods in multi-allergen protocols. In conclusion, omalizumab used in conjunction with immunotherapy has shown promising results, especially in the reduction of adverse reactions. At this stage, larger, randomized, placebo-controlled trials are needed to better identify those patients who would benefit the most from the addition of omalizumab to immunotherapy, as well as optimal dosing strategies and duration of treatment.

Venom immunotherapy in patients with allergic reactions to insect stings

INTRODUCTION

Allergy to Hymenoptera (Apis mellifera, Vespula species, Polistes species, Vespa crabro) venom can be safely and effectively treated by venom immunotherapy (VIT), which in the 40 years since its introduction has been able to prevent reactions to stings, and to treatment as well, though systemic reactions, occasionally severe, are possible. Areas covered: We reviewed the recent literature on VIT by searching in PubMed for the terms 'venom immunotherapy' and 'Hymenoptera venom immunotherapy' to highlight the current status of VIT and the likely development in the coming years. Expert commentary: VIT, provided the correct choice of the venom and adequate venom preparations and maintenance doses are used, is a treatment of great value in preventing systemic reactions to Hymenoptera stings. A 5-year duration ensures a prolonged tolerance to stings following VIT discontinuation, unless patients suffer from mastocytosis. In fact, due to reports of fatal reactions after stopping VIT, patients with mastocytosis, or with very severe reactions to stings, need an indefinite duration of treatment.

Preventive actions of allergen immunotherapy: the facts and the effects in search of evidence

Allergen immunotherapy (AIT) is the only treatment that works on the causes of allergy. Available AIT nowadays are subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) for allergic rhinitis and asthma, while for allergy to Hymenoptera venom only subcutaneous route is recommended. A bulk of trials and meta-analyses demonstrated that efficacy and safety of AIT in decreasing allergic clinical symptoms and use of rescue medications, while its preventive capacity is yet under investigation. The most important of these effects is the prevention of potentially fatal anaphylactic reactions to Hymenoptera stings by venom immunotherapy (VIT). A certain number of studies thus far available showed that AIT, in both forms, is able to prevent the progress of allergic rhinitis into asthma and the development of new sensitizations. These effects should be related to the mechanisms of action of AIT. In fact, it has been demonstrated that both SCIT and SLIT are able to modify the allergen presentation by dendritic cells, with result in modification of the phenotype of allergen-specific T cells, switching from the typical of allergic inflammation Th2-type response to a Th1-type one. Also allergen-specific T regulatory (Treg) cells play a pivotal role by producing suppressive cytokines, such as IL-10 and TGF-beta. However, the only plain evidence of a preventive effect concerns VIT, while the other outcomes need to be furtherly investigated.

Wasp venomic: Unravelling the toxins arsenal of Polybia paulista venom and its potential pharmaceutical applications

Polybia paulista (Hymenoptera: Vespidae) is a neotropical social wasp from southeast Brazil. As most social Hymenoptera, venom from P. paulista comprises a complex mixture of bioactive toxins ranging from low molecular weight compounds to peptides and proteins. Several efforts have been made to elucidate the molecular composition of the P. paulista venom. Data derived from proteomic, peptidomic and allergomic analyses has enhanced our understanding of the whole envenoming process caused by the insect sting. The combined use of bioinformatics, -omics- and molecular biology tools have allowed the identification, characterization, in vitro synthesis and recombinant expression of several wasp venom toxins. Some of these P. paulista - derived bioactive compounds have been evaluated for the rational design of antivenoms and the improvement of allergy specific diagnosis and immunotherapy. Molecular characterization of crude venom extract has enabled the description and isolation of novel toxins with potential biotechnological applications. Here, we review the different approaches that have been used to unravel the venom composition of P. paulista. We also describe the main groups of P. paulista - venom toxins currently identified and analyze their potential in the development of component-resolved diagnosis of allergy, and in the rational design of antivenoms and novel bioactive drugs.

Dose-dependence of protection from systemic reactions to venom immunotherapy by omalizumab

BACKGROUND

Systemic reactions (SR) to venom immunotherapy (VIT) are rare but may occur, with a rate significantly higher for honeybee than for vespid VIT. In patients with repeated SRs to VIT it is difficult to reach the maintenance dose of venom and pre-treatment with omalizumab is indicated, as shown by some studies reporting its preventative capacity, when antihistamines and corticosteroids are ineffective.

CASE PRESENTATION

We present the case of a 47 years old woman allergic to bee venom who experienced two severe SRs after bee stings and several SRs to VIT with bee venom. Pre-treatment with antihistamines and corticosteroids as well as omalizumab at doses up to 300 mg was unsuccessful, while an omalizumab dose of 450 mg finally achieved in our patient the protection from SRs to VIT with 200 mcg of bee venom.

CONCLUSIONS

The search of the dose of omalizumab able to protect a patient with repeated SRs to VIT may be demanding, but this search is warranted by the need to provide to this kind of patient, by an adequate VIT, the protection from potentially life-threatening reactions.

Hymenoptera Allergy and Mast Cell Activation Syndromes

Mast cell activation syndrome (MCAS) can be diagnosed in patients with recurrent, severe symptoms from mast cell (MC)-derived mediators, which are transiently increased in serum and are attenuated by mediator-targeting drugs. When KIT-mutated, clonal MC are detected in these patients, a diagnosis of primary MCAS can be made. Severe systemic reactions to hymenoptera venom (HV) represent the most common form of anaphylaxis in patients with mastocytosis. Patients with primary MCAS and HV anaphylaxis are predominantly males and do not have skin lesions in the majority of cases, and anaphylaxis is characterized by hypotension and syncope in the absence of urticaria and angioedema. A normal value of tryptase (≤11.4 ng/ml) in these patients does not exclude a diagnosis of mastocytosis. Patients with primary MCAS and HV anaphylaxis have to undergo lifelong venom immunotherapy, in order to prevent further potentially fatal severe reactions.

Why do we study animal toxins?

Venom (toxins) is an important trait evolved along the evolutionary tree of animals. Our knowledges on venoms, such as their origins and loss, the biological relevance and the coevolutionary patterns with other organisms are greatly helpful in understanding many fundamental biological questions, i.e., the environmental adaptation and survival competition, the evolution shaped development and balance of venoms, and the sophisticated correlations among venom, immunity, body power, intelligence, their genetic basis, inherent association, as well as the cost-benefit and trade-offs of biological economy. Lethal animal envenomation can be found worldwide. However, from foe to friend, toxin studies have led lots of important discoveries and exciting avenues in deciphering and fighting human diseases, including the works awarded the Nobel Prize and lots of key clinic therapeutics. According to our survey, so far, only less than 0.1% of the toxins of the venomous animals in China have been explored. We emphasize on the similarities shared by venom and immune systems, as well as the studies of toxin knowledge-based physiological toxin-like proteins/peptides (TLPs). We propose the natural pairing hypothesis. Evolution links toxins with humans. Our mission is to find out the right natural pairings and interactions of our body elements with toxins, and with endogenous toxin-like molecules. Although, in nature, toxins may endanger human lives, but from a philosophical point of view, knowing them well is an effective way to better understand ourselves. So, this is why we study toxins.

Facing Hymenoptera Venom Allergy: From Natural to Recombinant Allergens

Along with food and drug allergic reactions, a Hymenoptera insect Sting (Apoidea, Vespidae, Formicidae) is one of the most common causes of anaphylaxis worldwide. Diagnoses of Hymenoptera venom allergy (HVA) and specific immunotherapy (SIT) have been based on the use of crude venom extracts. However, the incidence of cross-reactivity and low levels of sensibility during diagnosis, as well as the occurrence of nonspecific sensitization and undesired side effects during SIT, encourage the search for novel allergenic materials. Recombinant allergens are an interesting approach to improve allergy diagnosis and SIT because they circumvent major problems associated with the use of crude venom. Production of recombinant allergens depends on the profound molecular characterization of the natural counterpart by combining some “omics” approaches with high-throughput screening techniques and the selection of an appropriate system for heterologous expression. To date, several clinically relevant allergens and novel venom toxins have been identified, cloned and characterized, enabling a better understanding of the whole allergenic and envenoming processes. Here, we review recent findings on identification, molecular characterization and recombinant expression of Hymenoptera venom allergens and on the evaluation of these heterologous proteins as valuable tools for tackling remaining pitfalls on HVA diagnosis and immunotherapy.

Venom immunotherapy: clinical efficacy, safety and contraindications

Venom-specific immunotherapy (VIT) is considered for the treatment of patients with IgE-mediated systemic allergic reactions (SARs) after developing a Hymenoptera venom allergy. Tolerance is achieved in a majority of patients after only a few days or even hours of rush immunotherapy. After VIT discontinuation, the allergy returns in up to 15% of patients. During VIT, the majority of patients have local reactions at the site of venom injections. SARs to VIT are much more frequent in honeybee-treated patients than in wasp-treated patients. Increased baseline serum tryptase and increased allergen-specific sensitivity of basophils are other factors that might be associated with systemic reactions (SRs) during VIT. Severe SRs occur mainly during the build-up phase but can also occur in the maintenance phase of the VIT, even in patients with a well-tolerated dose-increase phase. Pre-treatment with humanized anti-IgE antibodies (omalizumab) is effective in patients with repeated SARs; however, this use of omalizumab is off-label. In highly exposed patients with a history of very severe reactions, there are virtually no absolute contraindications for VIT.

Risk associated with bee venom therapy: a systematic review and meta-analysis

OBJECTIVE

The safety of bee venom as a therapeutic compound has been extensively studied, resulting in the identification of potential adverse events, which range from trivial skin reactions that usually resolve over several days to life-threating severe immunological responses such as anaphylaxis. In this systematic review, we provide a summary of the types and prevalence of adverse events associated with bee venom therapy.

METHODS

We searched the literature using 12 databases from their inception to June 2014, without language restrictions. We included all types of clinical studies in which bee venom was used as a key intervention and adverse events that may have been causally related to bee venom therapy were reported.

RESULTS

A total of 145 studies, including 20 randomized controlled trials, 79 audits and cohort studies, 33 single-case studies, and 13 case series, were evaluated in this review. The median frequency of patients who experienced adverse events related to venom immunotherapy was 28.87% (interquartile range, 14.57-39.74) in the audit studies. Compared with normal saline injection, bee venom acupuncture showed a 261% increased relative risk for the occurrence of adverse events (relative risk, 3.61; 95% confidence interval, 2.10 to 6.20) in the randomized controlled trials, which might be overestimated or underestimated owing to the poor reporting quality of the included studies.

CONCLUSIONS

Adverse events related to bee venom therapy are frequent; therefore, practitioners of bee venom therapy should be cautious when applying it in daily clinical practice, and the practitioner's education and qualifications regarding the use of bee venom therapy should be ensured.

Inmunoterapia con alérgenos, ¿cuándo y por qué?

La inmunoterapia específica con alérgenos es el único tratamiento que modifica el curso natural de algunas enfermedades alérgicas como asma, rinitis, conjuntivitis, dermatitis atópica y alergia al veneno de himenópteros. Sin embargo, aún existe cierta controversia respecto a su seguridad y su utilidad clínica. En el presente artículo se presenta una revisión de los mecanismos moleculares, las indicaciones y contraindicaciones de dicha inmunoterapia, y se evalúan su seguridad y eficacia en cada una de estas enfermedades mediante casos ilustrativos y una breve revisión del tema.

Reactions to honeybee stings: an allergic prospective

PURPOSE OF REVIEW

The purpose of this article is to provide a brief overview of the events involved in honeybee allergy and to concisely update the reader on progress toward knowledge of honeybee venom (HBV), strides in solving diagnostic difficulties, and advancements in improving safety and efficacy of HBV immunotherapy.

RECENT FINDINGS

It is well known that honeybee allergy is unique in venom allergen and protein composition, diagnostic challenges, and immunotherapy safety and efficacy. Many new honeybee allergens have been recognized. Advances in testing, evaluation, and extract manipulation methods, many using recombinant technology, have allowed a greater ability to help with honeybee allergy diagnosis and resultant improvement in immunotherapy safety and evaluation of immunotherapy efficacy.

SUMMARY

In an effort to address many honeybee allergy concerns, specific advances have been recently made. Some recently characterized honeybee allergens appear to be major contributors to honeybee allergy. In the setting of double-positivity, cross-reacting carbohydrate determinants and other cross-reacting components in HBV have made diagnosis of honeybee allergy challenging. Recombinant technology, including component-resolved diagnostics, and other evolving testing methods should help clarify double-positivity, if not now, in the very near future. Purified HBV and possibly depot formulations for immunotherapy appear to make it more well tolerated. Recombinant methods may help with evaluation of immunotherapy's safety and efficacy.

An update on venom allergy

PURPOSE OF REVIEW

Allergic reactions to stinging insects may be unexpected, frightening, and severe. A clear understanding of recent advances in the field facilitates appropriate care of children who experience severe reactions to hymenoptera stings.

RECENT FINDINGS

Recent investigations have underscored the importance of appropriate patient selection for potentially life-saving venom immunotherapy. Venom immunotherapy is effective in preventing future anaphylaxis from hymenoptera stings. Immunotherapy is indicated for patients with a history of anaphylaxis. Children who develop large local swelling or strictly cutaneous systemic reactions generally do not require immunotherapy. Component resolved diagnostic testing has been investigated to clarify the possibility of multiple venom allergies in patients with sensitization to multiple venoms.

SUMMARY

Rapid recognition and treatment of anaphylaxis are critical. Subsequent education about avoiding future stings and attention to emergency preparedness with appropriate prescription of self-injectable epinephrine is important. Referral of patients who have experienced venom-associated anaphylaxis for possible venom immunotherapy can prevent future severe episodes of anaphylaxis resulting from stings.

Honeybee venom immunotherapy: certainties and pitfalls

The honeybee is an interesting insect because of the fundamental agricultural role it plays, together with the composition of its venom, which presents new diagnostic and immunotherapeutic challenges. This article examines various aspects of honeybee venom allergy from epidemiology to diagnosis and treatment, with special emphasis on venom immunotherapy (VIT). Honeybee venom allergy represents a risk factor for severe systemic reaction in challenged allergic patients, for the diminished effectiveness of VIT, for more frequent side effects during VIT and relapse after cessation of treatment. Some strategies are available for reducing the risk of honeybee VIT-induced side effects; however, there is considerable room for further improvement in these all-important areas. At the same time, sensitized and allergic beekeepers represent unique populations for epidemiological, venom allergy immunopathogenesis and VIT mechanism studies.