Deer ked-induced occupational allergic rhinoconjunctivitis

Reported Cases and Diagnostics of Occupational Insect Allergy: A Systematic Review

A significant part of adult-onset asthma is caused by occupational exposure to both high- and low-molecular-mass agents. Insects are occasionally described to cause occupational allergy in professions including anglers and fishers, laboratory workers, employees of aquaculture companies, farmers, bakers, sericulture workers and pet shop workers. Occupational insect allergies are often respiratory, causing asthma or rhinoconjunctivitis, but can be cutaneous as well. The European Union recently approved three insect species for human consumption, enabling an industry to develop where more employees could be exposed to insect products. This review overviews knowledge on occupational insect allergy risks and the tools used to diagnose employees. Despite the limited availability of commercial occupational insect allergy diagnostics, 60.9% of 164 included reports used skin prick tests and 63.4% of reports used specific IgE tests. In 21.9% of reports, a more elaborate diagnosis of occupational asthma was made by specific inhalation challenges or peak expiratory flow measurements at the workplace. In some work environments, 57% of employees were sensitized, and no less than 60% of employees reported work-related symptoms. Further development and optimization of specific diagnostics, together with strong primary prevention, may be vital to the health conditions of workers in the developing insect industry.

Two New Haplotypes of Bartonella sp. Isolated from Lipoptena fortisetosa (Diptera: Hippoboscidae) in SE Poland

Simple Summary

Lipoptena fortisetosa is a hematophagous ectoparasite of game animals feeding accidentally on companion animals and humans. Since the presence of numerous pathogenic microorganisms has been described in this species, monitoring its geographic distribution is of great epidemiological importance. To the best of our knowledge, we present two new haplotypes of Bartonella sp. isolated from L. fortisetosa in south-eastern Poland and confirm the presence of this invasive species in Lublin Voivodeship since 2013.

Abstract

Insects of the genus Lipoptena are parasitic arthropods with a broad host range. Due to the type of parasitism (hematophagy), their potential role as vectors of pathogens, i.e., Bartonella sp., Anaplasma phagocytophilum, Rickettsia spp., and Borrelia burgdorferi is considered. As the range of their occurrence has been changing dynamically in recent years and infestations of humans have increasingly been reported, these organisms are now the subject of numerous studies. Our research aimed to present the molecular characteristics of Bartonella sp. detected in Lipoptena fortisetosa parasitizing wild cervids in south-eastern Poland. Adults of Lipoptena spp. were collected from carcasses of roe deer and red deer between spring and autumn in 2013. The PCR method was used to detect Bartonella sp. in the insects. We report two new haplotypes of the rpoB gene of Bartonella sp. isolated from L. fortisetosa feeding on wild cervids in south-eastern Poland and the presence of this invasive ectoparasitic species in the studied area since 2013. Phylogenetic analyses of newly obtained Bartonella sp. haplotypes confirmed their unique position on the constructed tree and network topology. The rpoB gene sequences found belonging to lineage B support the view that this phylogenetic lineage represents a novel Bartonella species.

Molecular Detection of Selected Pathogens with Zoonotic Potential in Deer Keds (Lipoptena fortisetosa)

Deer keds are obligatory hematophagous ectoparasites of birds and mammals. Cervids serve as specific hosts for these insects. However, ked infestations have been observed in non-specific hosts, including humans, companion animals, and livestock. Lipoptena fortisetosa is a weakly studied ectoparasite, but there is evidence to indicate that it continues to spread across Europe. The existing knowledge on deer keds' impact on wildlife is superficial, and their veterinary importance is enigmatic. Lipoptena fortisetosa is a species with vectorial capacity, but potential pathogen transmission has not been assessed. The objective of this study was to evaluate the prevalence of selected pathogens in L. fortisetosa collected from cervids and host-seeking individuals in the environment. Out of 500 acquired samples, 307 (61.4%) had genetic material from at least one tested pathogen. Our research suggests that L. fortisetosa may be a potential vector of several pathogens, including A. phagocytophilum, Babesia spp., Bartonella spp., Borellia spp., Coxiella-like endosymbionts, Francisiella tularensis, Mycoplasma spp., Rickettsia spp., and Theileria spp.; however, further, more extensive investigations are required to confirm this. The results of the study indicate that keds can be used as biological markers for investigating the prevalence of vector-borne diseases in the population of free-ranging cervids.

Skin Lesions and Systemic Reactions in Humans Infested by Blackflies (Diptera: Simullidae) in Recreational Areas in Southeastern Poland

Due to their mass occurrence in some environments and high aggressiveness, blackflies (Simulium spp.) represent the most bothersome arthropods attacking humans. In this study, we describe the medical effects of blackfly infestations in humans in southeastern Poland. Local and systemic reactions to blackfly bites were monitored in 418 patients (61.24% of females and 38.76% of males) of medical centers. Only skin lesions at the site of the bites were found in 88.52% of the patients, whereas accompanying systemic reactions were diagnosed in 11.48%. The most common signs observed in the area of the bites were pruritus (94.74%), burning (55.02%), edema (44.02%), and erythema (40.91%). The skin lesions, which were most often grouped small papules and papular and purpuric lesions with a varied range, typically persisted for several days, or for several weeks in some patients. Statistical analyses confirmed that the persistence of the skin lesions did not depend on the sex of the patients and the number of blackfly infestations. The systemic reactions to the components of the blackfly saliva were manifested by headache, increased body temperature, arthralgia, lymphadenopathy, and menstrual disorders in the females. The patients were most often attacked simultaneously by many blackflies on exposed parts of the body, mainly the upper limb, lower limb, head, and neck areas. The investigations indicate that blackflies are an important etiological factor of dermatitis and other symptoms in humans; hence, they should be considered in clinical diagnosis.

Molecular characterization of Lipoptena cervi from environmental samples collected in Poland

The activity of Lipoptena cervi has intensified in Poland in recent years. The population genetics of this ectoparasite in Poland has never been described in the literature. The objectives of this study were to investigate the population genetics of L. cervi in selected regions of Poland, to evaluate molecular differences between L. cervi populations, and to determine phylogenetic relationships with other L. cervi sequences obtained in previous studies. In 2019, louse flies were sampled in natural mixed forests in five Polish voivodeships. Seven samples of L. cervi were collected from each voivodeship, and a total of 35 insects were analyzed molecularly. In the first step, Lipoptena spp. were identified to species level under a stereoscopic microscope. A fragment of the rRNA 16S gene was used as a marker to identify L. cervi by the PCR assay. The sequences were assigned accession numbers MT337409 to MT337416. A total of eight haplotypes were identified, two of which were dominant. In the obtained sequences, intraspecific pairwise genetic distances varied between 0.000 and 0.0496 (m = 0.0135; SD = 0.0149; SE = 0.0006; V = 110.11). Mean interpopulation diversity was d = 0.0135 (SE = 0.0027). The acquired nucleotide sequences were highly similar to the sequences from the Czech Republic (MF495940, AF322437), Lithuania (MN889542-MN889544) and Poland (MF541726–MF541729). The similarity with GenBank sequences ranged from 97.24% to 100%. This study revealed two dominant haplotypes of L. cervi in Poland, MT337410 and MT337413. Fragments of the analyzed sequences were detected in only one voivodeship. These findings suggest that the two dominant sequences are the oldest sequences that gave rise to the locally identified haplotypes. The lack of significant correlations with the sequences obtained in regions situated west of the research sites suggests the presence of other genetic populations in Europe.

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Eight new haplotypes with 0.000–0.0496 intraspecific pairwise genetic distance.

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Similarity with sequences from GenBank ranged from 97.24% to 100%.

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Two dominant haplotypes of L.cervi were observed in Central Europe.

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Part of the sequences have been discovered in single studied location.

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The lack of significant connections with sequences obtained from West Europe.

Exposure of Humans to Attacks by Deer Keds and Consequences of Their Bites-A Case Report with Environmental Background

Simple Summary

Lipoptena species, also named the deer ked or deer fly, are commonly encountered in temperate areas of Europe, northern China, and North America. Although wild animals seem to be the preferred hosts of these parasitic arthropods, it is increasingly being noted that humans are also directly threatened by their bites. Skin lesions evolving after Lipoptena bites are painful and often lead to the development of inflammation of the skin. Lipoptena species also pose a threat to the health of the host by transferring pathogenic factors, e.g., Bartonella schoenbuchensis, Borrelia burgdorferi, and Anaplasma phagocytophilum. For this reason, knowledge of symptoms caused by Lipoptena bites is worth promoting among not only scientists but also the general public.

Abstract

Insects of the genus Lipoptena, e.g., Lipoptena cervi and Lipoptena fortisetosa, are hematophagic ectoparasites mainly attacking deer, roe deer, moose, horses, and cattle. Humans may also be incidental hosts for these insects. The species are vectors of numerous pathogens, including Bartonella schoenbuchensis, Borrelia burgdorferi, and Anaplasma phagocytophilum. Due to the short time of feeding on humans, usually painless bites, and an initially small trace at the site of the bite, the symptoms reported by the patient may not be associated with deer ked infestation and infection with pathogens transmitted by these arthropods. The aim of the study was to describe the consequences of L. cervi bites in humans with detailed documentation of the development of skin lesions. The knowledge about skin lesions arising after deer ked bites may be useful in clinical practice for monitoring patients for the presence of pathogens transmitted by the parasites.

Collecting Deer Keds (Diptera: Hippoboscidae: Lipoptena Nitzsch, 1818 and Neolipoptena Bequaert, 1942) and Ticks (Acari: Ixodidae) From Hunter-Harvested Deer and Other Cervids

Deer keds (Diptera: Hippoboscidae: Lipoptena Nitzsch, 1818 and Neolipoptena Bequaert, 1942) are blood-feeding ectoparasites that primarily attack cervids and occasionally bite humans, while ticks may be found on cervids, but are more generalized in host choice. Recent detection of pathogens such as Anaplasma and Borrelia in deer keds and historical infections of tick-borne diseases provides reason to investigate these ectoparasites as vectors. However, previous methods employed to sample deer keds and ticks vary, making it difficult to standardize and compare ectoparasite burdens on cervids. Therefore, we propose a standardized protocol to collect deer keds and ticks from hunter-harvested deer, which combines previous methods of sampling, including timing of collections, dividing sections of the deer, and materials used in the collection process. We tested a three-section and a five-section sampling scheme in 2018 and 2019, respectively, and found that dividing the deer body into five sections provided more specificity in identifying where deer keds and ticks may be found on deer. Data from 2018 suggested that deer keds and ticks were found on all three sections (head, anterior, posterior), while data from 2019 suggested that more Ixodes scapularis were found on the head and deer keds were found on all body sections (head, dorsal anterior, dorsal posterior, ventral anterior, and ventral posterior). The protocol provides an efficient way to sample deer for deer keds and ticks and allows researchers to compare ectoparasite burdens across geographical regions. Furthermore, this protocol can be used to collect other ectoparasites from deer or other cervids.

A Technique for Dissecting the Salivary Glands From the Abdomens of Deer Keds (Diptera: Hippoboscidae: Lipoptena Nitzsch, 1818 and Neolipoptena Bequaert, 1942)

Deer keds (Diptera: Hippoboscidae: Lipoptena Nitzsch, 1818 and Neolipoptena Bequaert, 1942) are hematophagous ectoparasites of cervids that occasionally bite other mammals, including humans. In recent years, a number of arthropod-borne pathogens have been sequenced from deer keds. However, it is unclear if the pathogens are just present in host blood in the gut or if the pathogens are present in other organs (e.g., salivary glands) that would suggest that keds are competent vectors. Like other hippoboscoid flies, deer keds have extensive salivary glands that extend through the thorax and into the abdomen, so simply disarticulating and sequencing the thorax and abdomen separately does not circumvent the issues surrounding whole-body sequencing. Herein, we describe a technique for dissecting the terminal portion of the salivary glands from the abdomen in order to screen the thorax and salivary glands separately from the abdomen for arthropod-borne pathogens.

Keds, the enigmatic flies and their role as vectors of pathogens

Hippoboscid flies (Diptera: Hippoboscidae), commonly known as keds or louse flies, have been for long time overlooked by the scientific community, and their vector role of infectious agents to humans and domestic animals has been scantly investigated. This is partly due to the fact that the host range for most species is primarily restricted to wildlife, being rarely reported on domestic animals and humans. This led to a scarce scientific knowledge about their biology, ecology, behaviour, epidemiology as well as vector competence. However, the life history of some hippoboscid species, e.g., Melophagus ovinus, Lipoptena cervi and Hippobosca equina, suggests that these ectoparasites are important candidates to vector infectious disease agents (e.g., Rickettsia spp., Borrelia spp., Bartonella spp., Anaplasma phagocytophilum, Theileria ovis). Indeed, the peculiar biological and behavioural traits (i.e., obligatory blood sucking and reproductive physiology) of many ked species make them a suitable pabulum for pathogen's multiplication and for their transmission to receptive hosts. Therefore, studies focusing on the ked bio-ecological aspects as well as on their vector role are advocated along with the control of keds affecting different animal species. This review discusses current information on keds, highlighting their importance as vectors of pathogens of medical and veterinary concern to all animal species, with a special focus on mammals.

Comparison of Skin Lesions Caused by Ixodes ricinus Ticks and Lipoptena cervi Deer Keds Infesting Humans in the Natural Environment

Background: The territorial expansion and increased population size of haematophagous arthropods (i.e., the castor bean tick Ixodes ricinus (Ixodida: Ixodidae) and the deer ked Lipoptena cervi (Diptera: Hippoboscidae)) has enhanced the risk of human infestations in Europe. The aim of our study was to present skin lesions induced by tick and deer ked bites in patients from recreational forest regions in southeastern Poland and pay attention to features of skin changes that may be useful in differential diagnosis. Methods: We compare the skin lesions after I. ricinus and L. cervi bite and draw attention to the biological and ecological traits of both ectoparasites, which may be diagnostically relevant for determination of the cause of skin symptoms reported by patients. Results: I. ricinus bites lead to development of erythematous-infiltrative poorly demarcated lesions with a centrally located bite mark, which usually disappears within one to several days. In turn, L. cervi bites leave irregularly shaped scattered erythematous papules. The papules may persist for up to one year and are accompanied by itching. Conclusions: Correct assessment of the clinical picture and its association with an arthropod bite (e.g., tick or deer ked) is highly important for further diagnostic procedures (i.e., differentiation of skin lesions developing in tick-borne diseases and, consequently, correct choice of pharmacological therapy). I. ricinus and L. cervi differ in their developmental cycles and rhythms of activity, which indicates that both species should be considered potential causative agents in the differential diagnosis of skin lesions when the patient has been bitten by an arthropod in autumn and winter months.

Deer Keds (Diptera: Hippoboscidae: Lipoptena and Neolipoptena) in the United States and Canada: New State and County Records, Pathogen Records, and an Illustrated Key to Species

Deer keds (Diptera: Hippoboscidae: Lipoptena Nitzsch, 1818 and Neolipoptena Bequaert, 1942) are parasitic flies that primarily attack cervids and occasionally bite humans. Recent reports have documented nearly half a dozen pathogens in deer keds, but it is unknown whether keds are competent vectors. Although geographic ranges of the four North American deer ked species are known generally, precise limits are not well understood. If keds are competent vectors, knowing where they occur will inform the risk of pathogen transmission to people and animals. Herein, we report deer ked occurrence by county in the United States and Canada, including 7 new state and 91 new county/parish/administrative district records. We also include a key to North American deer ked species to facilitate specimen identification.

Invasion rate of deer ked depends on spatiotemporal variation in host density

Invasive parasites are of great global concern. Understanding the factors influencing the spread of invading pest species is a first step in developing effective countermeasures. Growing empirical evidence suggests that spread rates are essentially influenced by spatiotemporal dynamics of host-parasite interactions, yet approaches modelling spread rate have typically assumed static environmental conditions. We analysed invasion history of the deer ked (Lipoptena cervi) in Finland with a diffusion-reaction model, which assumed either the movement rate, the population growth rate, or both rates may depend on spatial and temporal distribution of moose (Alces alces), the main host of deer ked. We fitted the model to the data in a Bayesian framework, and used the Bayesian information criterion to show that accounting for the variation in local moose density improved the model's ability to describe the pattern of the invasion. The highest ranked model predicted higher movement rate and growth rate of deer ked with increasing moose density. Our results suggest that the historic increase in host density has facilitated the spread of the deer ked. Our approach illustrates how information about the ecology of an invasive species can be extracted from the spatial pattern of spread even with rather limited data.

Do small mammals prey upon an invasive ectoparasite of cervids?

Predation is often considered an important factor for population regulation and in some cases for the invasion success of prey. Small mammalian predation may be a major force in the population regulation of many ground-dwelling invertebrate species. The deer ked ( Lipoptena cervi (L., 1758)) is an ectoparasitic fly of cervids. The species has a large distribution area and it has relatively rapidly spread in northern Europe during the previous four decades. The factors possibly regulating the distribution and invasion of this fly are poorly known. During the off-host stage of several months, pupae of deer ked are likely exposed to many ground-dwelling predators. To study whether small mammals would feed on deer keds, we conducted experiments by serving pupae of deer ked to wild-captured common shrews ( Sorex araneus L., 1758), bank voles ( Myodes glareolus (Schreber, 1780)), field voles ( Microtus agrestis (L., 1761)), and semi-wild bank voles, and assessed pupal survival. As a control, we provided alternative food including common nutrients used by small mammals in their natural habitats. The results show that variable amounts of pupae of deer ked are consumed by all small-mammal species studied. Surprisingly, insectivorous and most of the time food-constrained shrews consumed less pupae than granivorous–herbivorous voles.

Hippobosca longipennis--a potential intermediate host of a species of Acanthocheilonema in dogs in northern India

Background

Hippobosca longipennis (the 'dog louse fly') is a blood sucking ectoparasite found on wild carnivores such as cheetahs and lions and domesticated and feral dogs in Africa, the Middle East and Asia, including China. Known as an intermediate host for Acanthocheilonema dracunculoides and a transport host for Cheyletiella yasguri, it has also been suggested that H. longipennis may be a vector for other pathogens, including Acanthocheilonema sp.? nov., which was recently reported to infect up to 48% of dogs in northern India where this species of fly is known to commonly infest dogs. To test this hypothesis, hippoboscid flies feeding on dogs in Ladakh in northern India were collected and subjected to microscopic dissection.

Results

A total of 12 infective larvae were found in 10 out of 65 flies dissected; 9 from the head, 2 from the thorax and 1 from the abdomen. The larvae averaged 2, 900 (± 60) μm in length and 34 (± 5) μm in width and possessed morphological features characteristic of the family Onchocercidae. Genetic analysis and comparison of the 18S, ITS-2, 12S and cox-1 genes confirmed the identity of the larvae as the Acanthocheilonema sp.? nov. reported in dogs in Ladakh.

Conclusion

This study provides evidence for a potential intermediate host-parasite relationship between H. longipennis and the canine Acanthocheilonema sp.? nov. in northern India.

Northward invasion of the parasitic deer ked ( Lipoptena cervi), is there geographical variation in pupal size and development duration?

The deer ked (Lipoptena cervi) is a common ectoparasite of cervids. During the last decades the species has rapidly invaded in northern Europe, especially in Finland, towards the north and increased its prevalence on the moose population. Consequently, during this rapid invasion the deer ked has faced more severe climatic conditions. We studied whether pupal size (measured as pupal weight) and pupal development duration of the deer ked varies along historical invasion zones and temperature zones towards north in Finland. Moreover, we explored possible size- and gender-dependent variation in pupal development duration. We divided wild-collected pupae in respect to their origin in two ways: (1) temperature zones (from south-west to colder north-east) and (2) invasion history (from early to late establishment). We reared pupae in the controlled laboratory conditions in identical temperature and light conditions. Pupal size decreased towards north and the smaller pupae developed faster. However, the results do not show differences in pupal size or developmental characteristics between the invasion zones. This supports the idea of rapid developmental plasticity of the deer ked and that not the invasion history but the current temperature regime determines the life history of the deer ked when invading towards a colder environment.

Experiments on the ectoparasitic deer ked that often attacks humans; preferences for body parts, colour and temperature

The deer ked (Lipoptena cervi) can fail in its host search. Host search fails when an individual deer ked irreversibly accepts a host unsuitable for its reproduction (e.g. a human) and drops its wings. In northern Europe, the main host of the deer ked is the moose (Alces alces). The deer ked is increasingly causing serious problems for humans (for example, causing deer ked dermatitis) and is considered a threat for the recreational use of forests. The adult deer ked flies in early and mid-autumn to search for a host. Our aims were: (i) to study whether there are ways to avoid deer ked attacks by wearing particular clothing, and (ii) to evaluate deer ked host choice. Using human targets, we explored the cues the deer ked uses for host selection. We studied which part of the host body deer keds target and if body colour and temperature affect their choice. In our experiments, deer keds landed more on dark and red clothing than on white clothing. Moreover, deer keds mostly attacked the upper body parts and preferred the back side of the body over the front side. Finally, deer keds preferred the warmest areas of the host.

Anaphylactic reaction caused by a horse-fly species (Hippobosca equina)

A szerzők egy 46 éves nőbeteg esetét ismertetik, akinél egy légy okozta csípést követően szerencsés kimenetelű anafilaxiás reakció zajlott le. A hajas fejbőrön, a homlok és a haj találkozásánál rövid időn belül 15 cm átmérőjű kemény, savós varral fedett duzzanat, a homlokon ödéma jelentkezett. Nem sokkal ez után helyi és testszerte bőrpír, viszketés, kéz-, arc- és ajaködéma alakult ki, később jelentkező hidegrázás, émelygés, hányinger, hányás kíséretében. A befogott rovar egy határozókulcs segítségével történt meghatározás alapján lókullancslégy (Hippobosca equina) volt. Tudomásunk szerint e légyfaj csípése által kiváltott anafilaxiás reakcióról ez az első közölt eset Magyarországon. A lókullancslégy világszerte jelen van, hazánkban régóta ismert, leginkább legelőn, istállóban tartott lovakon, szamarakon, szarvasmarhákon, esetenként más állatfajokon naponta többször szív vért. Vektorként különféle kórokozókat terjeszthet. Esetismertetésünkkel a lókullancslégycsípésre és a csípés okozta klinikai tünetekre kívánjuk felhívni a családorvosok és a klinikusok figyelmét, mivel a rovarcsípések diagnosztizálása terén nem rendelkeznek kellő tapasztalattal és nem gondolnak erre a lehetőségre.

Occupational rhinitis

PURPOSE OF REVIEW

This review updates existing knowledge on occupational rhinitis based on epidemiological and clinical research studies published from 2003 to 2005.

RECENT FINDINGS

The review covers new developments on the pathophysiology, diagnosis, monitoring and management of occupational rhinitis. This article also provides updated information on the prevalence and incidence of both occupational rhinitis and work-related symptoms of rhinitis, as well as on causal agents and personal risk factors associated with this condition.

SUMMARY

Occupational rhinitis is frequently under-diagnosed due to a lack of physician awareness. Diagnosis is suspected when symptoms occur in relation to work. Differentiating between immunological sensitization and irritation may be difficult. Given the high prevalence of rhinitis in the general population from all causes, objective tests confirming the occupational origin are essential. Measures of inflammatory parameters via nasal lavage and objective assessment of nasal congestion both offer practical means of monitoring responses. Growing experience with acoustic rhinometry and peak nasal inspiratory flow suggests that these methods will have an increasingly important role in monitoring and diagnosing in the future. Recent findings indicate that work-related rhinitis is to some extent preventable. Surveillance of sensitized workers may allow early detection of occupational rhinitis.

Occupational upper airway disease

PURPOSE OF REVIEW

This article reviews recent findings concerning occupational upper airway diseases, which, although very frequent, are usually not considered serious. However, the concept of the 'united airway', evoked during recent years, should change our attitude regarding these diseases. Moreover, new agents in the occupational environment must be characterized. Furthermore, exposure to carcinogens has changed over the years, and in most cases risk should be reassessed.

RECENT FINDINGS

Recent findings concerning work-related upper airway diseases caused by allergens and irritants, and their relationship to lower airway diseases, are reviewed. Findings of studies aimed at characterizing occupational allergens of plant and animal origin are presented. Recognition of work-related upper airway diseases both in clinic and in epidemiological studies is discussed. Current evidence on occupational cancer of the upper airways, its risk factors and changes in them over the years resulting from preventative measures are also described.

SUMMARY

There is significant evidence that occupational allergic diseases of the upper airways can pose important health problems because they represent an early stage of allergy throughout the respiratory system. However, how to detect those rhinitic patients who will develop asthma remains unresolved. New occupational health problems due to irritants were recently reported, and both follow-up studies and evaluations of their implications for the lower airways are warranted. Although preventative measures have been effective to some extent, risk for occupational cancer of the upper airways persists and more targeted epidemiological studies in this area are needed.