Gamasoidosis | |
---|---|
Other names | Acariasis, avian mite dermatitis, bird mite dermatitis, fowl mite dermatitis, dermanyssosis |
Dermanyssus gallinae piercing skin with its long chelicerae to reach dermal capillaries (not to scale). | |
Specialty | Dermatology, medical parasitology |
Symptoms | Pruritic erythematous papules, macules, urticaria, itching, skin irritation |
Causes | Infestation with avian mites ( Dermanyssus and Ornithonyssus species) |
Risk factors | Close proximity to birds or infested environments, urban nesting birds, poultry farming |
Diagnostic method | Clinical signs, microscopic identification of mites, dermatoscopy |
Differential diagnosis | Scabies, cheyletiellosis, trombiculosis, bedbug infestations, urticarial dermatitis, delusional parasitosis |
Frequency | Increasing in urban and occupational settings |
Gamasoidosis, also known as dermanyssosis, is a frequently unrecognized form of zoonotic dermatitis, following human infestation with avian mites of the genera Dermanyssus or Ornithonyssus . It is characterized by pruritic erythematous papules, macules and urticaria, with itching and irritation resulting from the saliva the mites secrete while feeding. These bites are observed all over the body. The avian mite Dermanyssus gallinae can also infest various parts of the body, including the ear canal and scalp.
Diagnosis is challenging due to the mites' size, requiring microscopic identification by a medical entomologist, and the clinical symptoms often mimic other conditions, such as scabies or allergic reactions. The atypical or delayed responses to mite bites, coupled with widespread ignorance and misinformation among healthcare providers, scientists, and pest control professionals, contribute to frequent underdiagnosis and misdiagnosis, hindering effective management and treatment.
Gamasoidosis is linked to avian mites infesting residential, public and agricultural spaces, with a potential health threat due to the transmission of zoonotic pathogens by D. gallinae. Treatment involves eliminating mites from the environment—a process complicated by their resilience and rapid reproduction—and managing patient symptoms, which are typically self-limiting but may require supportive care.
The condition poses a growing public health concern, linked to urbanization, occupational risks, and zoonotic pathogens. Limited awareness and misdiagnoses highlight the need for a "One Health" approach, integrating experts to improve diagnosis, prevention, and treatment for better human and animal health.
Avian mite bites induce a non-specific dermatitis. [2] Common symptoms include pruritic erythematous papules, [3] with a size of 1–3 mm, [4] and a central punctum, [5] as well as macules and urticaria. [2] Individuals frequently describe repeated or long-term episodes of papular outbreaks, often appearing in clusters and accompanied by severe itching sensations. [6] Itching and skin irritation result from the saliva secreted by the mites during feeding. [7]
Bites can be found anywhere on the body. [6] Described areas affected include the waist, trunk, upper extremities, abdomen, legs, finger webs, axillae, groin, buttocks, and face. [4] [8] [9] Bites are frequently reported to be grouped and more pronounced in areas where clothing applies pressure, such as along a belt line or beneath the breasts. [4] When feeding happens during sleep, bedding may show red stains from crushed mites or their droppings. [4]
Additional symptoms include pinpricks, secondary infections, scarring and hyperpigmentation. [10]
Dermanyssus gallinae can infest the ear canal, causing symptoms such as itching, inflammation, and discharge. [11] It can also affect the scalp, with severe nighttime itching as a characteristic symptom, [12] and has been reported to infest the nares, orbits, eyelids, and genitourinary and rectal areas. [6]
Instances of systemic allergies, such as asthma and allergic rhinitis, linked to Ornithonyssus sylviarum have been documented. However, Kavallari et al. note that there are no reported cases of systemic allergies caused by Dermanyssus mites to date. [13]
Gamasoidosis occurs after human contact with blood-feeding gamasid avian mites of the genera of Ornithonyssus ( Mesostigmata: Macronyssidae ) and Dermanyssus (Mesostigmata: Dermanyssidae ). [14] Species implicated include the red mite (Dermanyssus gallinae), [15] tropical fowl mite ( Ornithonyssus bursa ) [7] and northern fowl mite (Ornithonyssus sylviarum). [15] These mites typically infest birds such as canaries, [16] sparrows, starlings, pigeons, [17] and poultry. [18]
When avian hosts are unavailable, these free-living mites may opportunistically feed on other animals, including humans. [14] It has been hypothesized that D. gallinae is capable of learning "to associate non-host skin with a blood-meal if the host selection process permitted feeding." [19] This, combined with their generalist strategy for host-seeking and the ability to digest non-avian blood, could explain their observed expansion to include mammals and humans as hosts. [19]
The rise in urbanization, particularly in warmer regions where avian mites flourish, has led to a greater incidence of gamasoidosis. [9] Urban gamasoidosis is associated with window-sills, ventilation and air-conditioning intakes, roofs and eaves, which serve as shelters for nesting birds. [14] [20]
Gamasoidosis in farm workers is associated with poultry farms, with a "19% incidence of contact dermatitis reported in a two-year survey of workers on 58 European poultry farms". [18] D. gallinae exposure is so common that it is considered an occupational hazard for these workers. [19]
Pets such as canaries, cats, dogs, hamsters, and gerbils are also susceptible to infestation by avian mites. [5] [16] [21] [22] Non-avian infestations may be underdiagnosed or underestimated, suggesting a need for increased awareness among veterinarians to improve diagnosis and treatment in such cases. [22]
For pets, there are currently no registered products for treating gamasoidosis in mammals. The scientific literature documents medications which have been used off-label to treat the condition, including sarolaner in dogs, selamectin in cats and permethrin in horses. [23]
Dermatitis is also associated with rodents infested with the tropical rat mite ( Ornithonyssus bacoti ), [24] [25] spiny rat mite (Laelaps echidnina) [26] and house-mouse mite ( Liponyssoides sanguineus ), where the condition is known as rodent mite dermatitis. [27]
Diagnoses of gamasoidosis have a long history, with "cases [...] reported since the 17th century, documented in the leading medical literature since at least the 1920s." [19] The first case of human infestation was suspected by Willan in 1809. Later, in 1828, Saint-Vincent became the first to identify the parasite on the skin of an affected person. [6] Kavallari et al. highlight that since 1936, 105 cases of D. gallinae infestations in humans have been documented in the literature. [13] D. gallinae's digestion of human blood was first documented in 1958. [28]
Avian and rodent mites have been documented as infesting residential buildings, work spaces, schools and hospitals. [24] [19] Despite this, widespread ignorance and misinformation about human infestation with D. gallinae exists across the healthcare, scientific, and pest control sectors, which in turn has led to increasing numbers of infestations and a dangerous propagation of the disease. [10]
Diagnosing avian mites can be difficult because their tiny size renders them almost invisible without magnification. [29] They are between 0.3 to 1 mm in length and have oval-shaped bodies, featuring four pairs of legs. Their coloration is translucent brown prior to feeding, transitioning to a reddish hue once they have consumed a meal. [9] Understanding the specific bite reactions of avian mites can aid clinicians in identifying and addressing this perplexing dermatologic condition. [9]
Because gamasoidosis is a rare diagnosis and its skin reactions are often atypical, most physicians are unfamiliar with the condition. As a result, gamasoidosis is frequently overlooked or misdiagnosed. [4] [18] [30] One misdiagnosis is scabies; [9] however, unlike scabies mites, avian mites can be seen with the naked eye and do not burrow. [9] Bites can also be mistaken for those caused by other conditions such as cheyletiellosis ( Cheyletiella ), trombiculosis ( Trombicula ), bedbug infestations ( Cimex lectularius ), or urticarial dermatitis. Additionally, these lesions are sometimes misattributed to allergic reactions or misinterpreted as symptoms of delusional parasitosis. [30] Dermatoscopy can help differentiate mite infestations from delusional parasitosis, aiding in accurate diagnosis. [31]
Allergists and dermatologists should prioritize inspecting potential sources to locate, collect, and accurately identify mites, a task best handled by skilled parasitologists. [30] Identification of the species is best carried out by a medical entomologist using a microscope. [15] Distinguishing Ornithonyssus from Dermanyssus and identifying cryptic species within D. gallinae is difficult due to overlapping traits and reproductive isolation. D. gallinae mainly infests poultry globally, while special lineage L1 targets pigeons, posing zoonotic risks in urban areas. DNA analysis, including mitochondrial markers, is required for precise identification. [14] Accurate species determination is crucial for recommending appropriate treatment methods. [4]
Gamasoidosis usually affects only one person in a household, as the condition requires both mite exposure and an allergic sensitivity. However, there have been reported cases where all members of a nuclear family experience symptoms in response to avian mite bites. [9]
Many cases of gamasoidosis go unreported, suggesting that the actual incidence is higher than generally believed. [18] As a result, in cases of unexplained bites in residential areas, the involvement of D. gallinae should always be considered, [17] especially during late spring and early summer when wild birds make their nests. [8] Diagnosing the responsible agent in symptomatic workers can be challenging. Over time, workers may develop a tolerance to mite bites, decreasing the likelihood of reporting such incidents. Nonetheless, outbreaks can occur after periods of reduced exposure or when new employees are introduced to the workplace. [13]
The life cycle of the mite is an important method of diagnosis. [10] Avian mites, like D. gallinae, are temporary parasites that hide in dark spaces during the day. Their life cycle, from egg to adult, can be completed in seven days in warm conditions. [14] When avian mites lose access to blood meals from nesting birds, they embark on a nocturnal search for alternative hosts. [29]
Blood-feeding starts at the protonymph stage, with adults feeding briefly at night every two to three days. Engorged females turn red and lay eggs soon after feeding. [14] They may also feed during the day if the room is sufficiently dark. [32] Attacks in public and office buildings tend to occur during the daytime. [4] O. bursa is an exception as it generally remains on its hosts and will feed during the day. [33]
In urban homes D. gallinae may be commonly found in the bedroom or where the patient sleeps, as they prefer to stay close to their host for optimal feeding. [34] Typically, it visits its host for 1–2 hours, departing after completing its blood meal. [20] They are highly mobile [5] and can locate potential hosts through temperature changes, vibrations, chemical signals, and carbon dioxide emissions. [19] Avian mites can travel through various pathways such as floors, walls, ceilings, and most commonly via ventilation or air conditioning systems. [9]
There is documented "co-occurrence of gamasoidosis and various immunosuppressive disorders" [19] and physicians should bear in mind that immunocompromised patients, patients that take corticosteroids, and patients with dementia may have a more severe infestation than healthy patients. [10] Despite this, while immunosuppression can "increase susceptibility, it is not necessarily a pre-requisite for infestation". [19]
Preventing gamasoidosis in urban areas is achieved by avoiding the proliferation of avian mites, by refraining from feeding birds and utilizing nets on building terraces to deter nesting in close proximity to human homes. It is crucial to remove and clean nests during the nesting season before birds can establish them and lay eggs. [35]
Maintaining cleanliness in workplaces and homes, such as frequent vacuuming and monitoring for feral birds, can help prevent future occurrences. Employees working with animals or animal products should undergo proper health and safety training to understand workplace risks, adopt safe practices, and utilize appropriate PPE when necessary. In some occupational environments, medical surveillance for high-risk workers might be advisable to detect and address infestations early. [13]
To achieve full recovery, it is essential to eradicate the mites from the patient's environment. This process involves identifying and removing sources of infestation, such as bird nests, and disinfecting affected areas with the help of pest control professionals. [20] However, complete eradication can be challenging due to several factors, including the resilience and behavior of avian mites. [10]
Avian mite species, such as Dermanyssus gallinae, can survive for over nine months without a blood meal. [36] [37] Their nocturnal behavior and tendency to leave the host after brief feeding sessions to hide in cracks and crevices further complicate eradication efforts. [10] Eggs and larvae are often located away from birds or humans, typically hidden in hard-to-reach crevices that may be distant from treated areas. [38]
Under favorable conditions, avian mite populations can expand rapidly. [39] For instance, a single female mite can lay up to 30 eggs in her lifetime [39] and prolonged darkness can significantly accelerate their growth. [40] D. gallinae thrives at temperatures of 20–25°C and a relative humidity of 70–90%, while low humidity and extreme temperatures (below 5°C or above 45°C) hinder their development and survival. [36]
Avian mites are also capable of digesting human blood [41] and it is widely believed that they cannot reproduce without avian blood. [9] [42] [43] However, some studies, such as those by George et al., suggest that avian mites may develop and sustain prolonged infestations on human blood, challenging this assumption. [19]
The treatment of gamasoidosis is further complicated by pesticide resistance among avian mites and their diverse ecological behaviors, which require tailored treatment strategies. [10] Employing a variety of techniques, following a Integrated Pest Management approach, can reduce the likelihood of major re-infestations and limit the development of resistance to specific insecticides. [38]
Attempts to eradicate infestations are often prolonged and ineffective, leading to significant financial burdens and psychological issues such as depression, particularly when patients are forced to relocate or invest heavily in pest control measures. [10]
Patients are advised to: [4]
Avian mites are typically not found on human skin, as they tend to leave their host after feeding and are capable of moving with remarkable speed. [9] However, patients are recommended to shower frequently. [4] In the case of scalp infestation, treatments with 1% permethrin shampoo can be used to remove the mites. [44] For ear canal infestation, aural toilet is recommended with a course of 1% permethrin to be used as ear drops and for infected wax to be removed by a professional. [11]
Oral antihistamines and topical corticosteroids can be used to alleviate discomfort. However, as the rash is self-limiting, no targeted therapy is generally necessary. While topical antihistamines may offer temporary relief, their use is generally discouraged due to the potential risk of adverse skin reactions, such as allergic contact dermatitis. Patients can be comforted knowing that the lesions typically resolve on their own over time. Although subsequent exposure to biting arthropods might trigger occasional flare-ups, most people gradually build a tolerance. [13]
Gamasoidosis, particularly caused by D. gallinae, is source of growing concern in human medicine, due to factors such as limited awareness among medical specialists, lack of interdisciplinary collaboration, misdiagnoses, and an absence of diagnostic tools. [4] Occurrences of gamasoidosis have become more frequent in recent years, especially in residential environments, often linked to synanthropic birds. [19] The condition has been described as a worldwide infestation, with cases being identified in countries including Denmark, Egypt, France, Iran, Japan, Montenegro, Morocco, the Netherlands, Norway, Serbia, Turkey, and the United Kingdom. [28] A "One Health" approach has been recommended to remedy this, with microbiologists, veterinarians, parasitologists, epidemiologists, environmental scientists, and clinicians working together to treat the disease. [4]
D. gallinae may pose a threat to public health as the mite may be a vector or reservoir of several zoonotic pathogens, [19] such as Chlamydia psittaci , Erysipelothrix rhusiopathiae , Salmonella spp., [19] Mycobacterium spp., Coxiella burnetii , Bartonella spp., [45] Borrelia afzelii , [46] Venezuelan equine encephalitis virus, Eastern equine encephalitis virus, and Fowlpox virus. [47] An association has not been found with gamasoidosis and alpha-gal allergy. [48]
The rock dove, rock pigeon, or common pigeon is a member of the bird family Columbidae. In common usage, it is often simply referred to as the "pigeon", although this is the wild form of the bird; the pigeons most familiar to people are the domesticated form of the wild rock dove.
Mites are small arachnids. Mites span two large orders of arachnids, the Acariformes and the Parasitiformes, which were historically grouped together in the subclass Acari. However, most recent genetic analyses do not recover the two as each other's closest relative within Arachnida, rendering the group non-monophyletic. Most mites are tiny, less than 1 mm (0.04 in) in length, and have a simple, unsegmented body plan. The small size of most species makes them easily overlooked; some species live in water, many live in soil as decomposers, others live on plants, sometimes creating galls, while others are predators or parasites. This last type includes the commercially destructive Varroa parasite of honey bees, as well as scabies mites of humans. Most species are harmless to humans, but a few are associated with allergies or may transmit diseases.
Demodex is a genus of tiny mites that live in or near hair follicles of mammals. Around 65 species of Demodex are known. Two species live on humans: Demodex folliculorum and Demodex brevis, both frequently referred to as eyelash mites, alternatively face mites or skin mites.
Swimmer's itch, cercarial dermatitis or schistosome dermatitis is a short-term allergic contact dermatitis occurring in the skin of humans that have been infected by water-borne schistosomes, a type of flatworm. It is common in freshwater, brackish and marine habitats worldwide. The incidence of this condition may be increasing, although this may be attributed to better monitoring and reporting. Nevertheless, the condition is considered to be an emerging infectious disease.
Poultry diseases occur in poultry, which are domesticated birds kept for their meat, eggs or feathers. Poultry species include the chicken, turkey, duck, goose and ostrich.
Acariasis is an infestation with mites.
Dermanyssus gallinae is a haematophagous ectoparasite of poultry. It has been implicated as a vector of several major pathogenic diseases. Despite its common names, it has a wide range of hosts including several species of wild birds and mammals, including humans, where the condition it causes is called gamasoidosis. In both size and appearance, it resembles the northern fowl mite, Ornithonyssus sylviarum.
Mesostigmata is an order of mites belonging to the Parasitiformes. They are by far the largest group of Parasitiformes, with over 8,000 species in 130 families. Mesostigmata includes parasitic as well as free-living and predatory forms. They can be recognized by the single pair of spiracles positioned laterally on the body.
Ornithonyssus is a mite genus of the family Macronyssidae.
Ornithonyssus bacoti is a hematophagous parasite. It feeds on blood and serum from many hosts. O. bacoti can be found and cause disease on rats and wild rodents most commonly, but also small mammals and humans when other hosts are scarce. Outbreaks tend to occur in older, less maintained buildings. The mite, however, can travel several hundred feet on its own if necessary to find a host and can survive for extended periods of time without a host. This, along with the nonspecific dermatitis it causes, can prevent accurate and fast diagnosis of rat mite dermatitis. The scarcity of reports, due in part to misdiagnosis and also the mildness of its symptoms, makes the disease seem less common than it is. The tropical rat mite can be found in both temperate and tropical regions or rather all continents except the Arctic and Antarctic.
Pyemotes tritici is a species of mite known as the grain itch mite or straw itch mite. It is a cosmopolitan species that is found on straw, hay and stored grain. It is a parasite of small arthropods and is being investigated as a possible biological control of stored product pests. It is associated with dermatitis in humans, and it causes an itchy rash.
Dermanyssus is a genus of mites in the family Dermanyssidae. The etymology of the word Dermanyssus is from the Greek: derma, meaning skin, and nyssein, meaning bite.
Dermanyssoidea is a superfamily of mites, including most of the mites which parasitise vertebrates.
Androlaelaps casalis, formerly known as Haemolaelaps casalis, is a species of predatory mite that feeds on other mites and small invertebrates. It cannot bite or sting birds and humans because its mandibles are not designed for sucking but for predation on other mites. Because Androlaelaps casalis mites feed off parasitic mites like Dermanyssus gallinae, individuals with red colored abdomens can be found. This is not due to any blood-sucking by A. casalis but is because it has ingested blood-engorged parasitic mites. There is some evidence that it may be associated with dermatitis in humans.
Ornithonyssus bursa is a species of mite. It is most often a parasite of birds, but also has been found to bite humans and two species of mammals. It usually lives in birds' feathers, but for laying its eggs, it more often uses their nests rather than their feathers. Tropical fowl mites undergo five stages during their development: egg, larva, protonymph, deutonymph, and adult. During the last two stages, they suck blood from their host for food. They are often diurnal, whereas northern fowl mites are nocturnal in nature.
Ornithonyssus sylviarum is a haematophagous ectoparasite of poultry. In both size and appearance, it resembles the red mite, Dermanyssus gallinae. They primarily infect egg laying chickens. They contribute to economic damage and feed on their host's blood which leads to lowering the egg production and feed conversion efficiency. Anemia or death can be an effect of a high amount of infestation within the birds. While they mainly do target wild birds they can also become permanent ectoparasites in the domestic poultry. The main nesting sites are generally in a close proximity to poultry coops.
Cheyletiella yasguri is a species of mites from the genus Cheyletiella popularly known as "walking dandruff" and one of the many ectoparasites that targets domestic dogs.
Mites that infest and parasitize domestic animals cause disease and loss of production. Mites are small invertebrates, most of which are free living but some are parasitic. Mites are similar to ticks and both comprise the order Acari in the phylum Arthropoda. Mites are highly varied and their classification is complex; a simple grouping is used in this introductory article. Vernacular terms to describe diseases caused by mites include scab, mange, and scabies. Mites and ticks have substantially different biology from, and are classed separately from, insects. Mites of domestic animals cause important types of skin disease, and some mites infest other organs. Diagnosis of mite infestations can be difficult because of the small size of most mites, but understanding how mites are adapted to feed within the structure of the skin is useful.
Mites are small crawling animals related to ticks and spiders. Most mites are free-living and harmless. Other mites are parasitic, and those that infest livestock animals cause many diseases that are widespread, reduce production and profit for farmers, and are expensive to control.
Rodent mite dermatitis is an often unrecognized ectoparasitosis occurring after human contact with haematophagous mesostigmatid mites that infest rodents, such as house mice, rats and hamsters. The condition is associated with the tropical rat mite, spiny rat mite and house mouse mite which opportunistically feed on humans. Rodent mites are capable of surviving for long periods without feeding and travelling long distances when seeking hosts. Cases have been reported in homes, libraries, hospitals and care homes. A similar condition, known as gamasoidosis, is caused by avian mites.