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Damage done to skin of cattle and defects of raw leather, which are caused by ixodid and demodecid ticks, parasitic on animals, are described. Losses of tanning industry amount to 1.6 to 3.7 thousand roubles per each thousand of finished box-calf leathers.
Rabbits infested for the first time with Psoroptes cuniculi (Group A) and heavily infested ones with unknown aetiology (Group B) were examined for specific serum antibody activity and responsiveness of their peripheral blood lymphocytes by the enzyme-linked immunosorbent assay and lymphocyte transformation assay methods. These parameters were examined after treatment with ivermectin and after subsequent challenge infestation with P. cuniculi. Group A rabbits developed a small number of mite-caused lesions, and exhibited a significant P. cuniculi antigen-induced T cell response and a high level of specific serum antibody. However, both lymphocyte responsiveness and antibody production were observed to be suppressed in Group B rabbits that were highly susceptible to P. cuniculi.
The study of the role played by birds in the distribution of various bacterial, viral and parasitic infections is increasingly from year to year, taking into consideration the flying ability of birds and their migration for food and vital processes. Two of the common Egyptian resident birds, house sparrow (Passer d. niloticus) and laughing dove (Streptopelia s. aegyptiaca) were chosen to study their mite fauna. The overall mite index was 4.74 on the house sparrow and 7.22 on the laughing dove. As to mites, a total of 31 species belonging to 23 genera, 17 families and 3 suborders were collected. The common mites on both types of birds were 22 species. Three species only on house sparrow, and six species only on laughing dove. The house sparrow served host for 25 mite species and the laughing dove served host for 28 mite species. The infestation rates of mites on house sparrow ranged between 1.11% to 23.33% and 0.21% to 34.54% in Sharkia and Qalyobia governorates respectively. For laughing dove, the mite infestation rates ranged between 0.82% to 50% and 3.45% to 55.17% for both governorates respectively. Some of the collected mites have medical and/or veterinary importance. The whole results were discussed.
Mange was diagnosed in two North American racoons (Procyon lotor) at Kamakura City in Kanagawa Prefecture, Japan. The mites were identified morphologically as Notoedres cati. Mite infestation affected the skin over the extremities and tail, and was characterized by moderate alopecia and erythematous dermatosis. Histopathologically, the affected skin showed marked epidermal hyperplasia and mites located within the parakeratotic stratum corneum. A slight dermal inflammatory response consisting principally of mononuclear cells was observed. N. cati mites were demonstrated in their tunnels using scanning electron microscopy (SEM). This is the first report of notoedric mange in racoons.
This survey was undertaken to determine the possible exposure of military personnel to house dust mites in ships, barracks, and homes in the Hampton Roads area of Virginia. During the period from April 1, 1982 through August 31, 1983, 524 dust samples were collected with vacuum cleaners. Mites were extracted from aliquots of dust, counted, and identified as to species and life stage. Dermatophagoides pterynssinus (European house dust mite) was more common in private homes, while Dermatophagoides farinae (North American house dust mite) was more common on ships. Berthing compartments had the highest density of mites of areas sampled aboard ships. There appears to be a trend between the density of personnel and mites. Ships had a smaller percentage of mite-infested samples than houses.
BACKGROUND: Individuals with allergies or asthma have had a long-standing bias against the use of chicken, goose, and duck feather pillows, comforters, quilts, and mattresses. OBJECTIVE: We show that raw, unprocessed feathers contain dust-mite allergen that is removed by washing, and that feather pillows, whether covered or not, do not internally accumulate dust-mite allergen when used in mite-infested bedrooms over a 3-month period. METHODS: Feathers obtained from six companies as unprocessed feathers (n = 8 batches) and processed feathers (n = 16 batches) were analyzed for dust-mite (Der p 1 and Der f 1) using monoclonal antibody-based immunoenzyametric assays with appropriate internal controls. Five pairs of new feather pillows (one covered and one uncovered) were placed in five bedrooms with known dust-mite contamination for 90 days. The pillows were then assayed for mite content. RESULTS: Dust-mite allergen was detected in 7 of 8 unprocessed feather samples; combined Der p 1 and Der f 1 mean = 524 ng/g, range 152 to 1,850 ng/g, whereas all 17 manufacturer-processed feather samples contained no detectable dust-mite. Although 4 of 5 bedrooms contained significant dust-mite allergen (>2,000 ng or Der p 1 and f 1, range 2,500 to 10,300 ng/g), none of the 90-day feather pillows became contaminated by dust-mite allergen even in the absence of a pillow cover. CONCLUSIONS: Feathers washed using industrial methods do not contain detectable dust-mite allergen. Pillows manufactured with processed feathers, whether encased in a dust cover or not, do not become contaminated by dust-mite allergen after 90 days of use in environments containing significant dust-mite allergen contamination.
Seventy similar bungalows constructed between 1968 and 1970 in the same suburban area of Stockholm were investigated regarding the content of house dust mite allergen, absolute indoor humidity, type of ventilation and basement construction. Houses with mechanical exhaust and supply ventilation had an indoor humidity above 7 g/kg less often than houses without this type of ventilation (Odds ratio 0.1, 95% confidence interval 0.0-0.2). Furthermore, only five of the 24 houses with exhaust and supply ventilation contained mattress dust mite allergen concentrations exceeding the median value (98.5 ng/g) compared with 30 of 46 hours which did not have such ventilation (odds ratio = 0.1, C.I. 0.0-0.5). Houses with both natural ventilation and crawl space basement harboured significantly less mattress mite allergen than houses having the same type of ventilation, but with a concrete slab basement. In a cold temperature climate, type of building construction and ventilation seem to be important for the occurrence of house dust mite allergens in dwellings. Our results indicate that modern energy-efficient houses should be equipped with mechanical exhaust and supply ventilation to reduce indoor air humidity during the dry winter months and the risk of mite infestation.
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We studied the parasitism by larvae of the chigger mite Eutrombicula alfreddugesi on the lizard community of Restinga de Jurubatiba, Rio de Janeiro State, Southeastern Brazil. We investigated the patterns of infestation (prevalence and intensity) of chigger mites in four sympatric lizards: Tropidurus torquatus, Mabuya agilis, M. macrorhyncha and Cnemidophorus littoralis. All lizards collected were checked for the presence of mites, which were counted under stereomicroscope. We tested the relationship between intensity of infestation and lizard body size for each species using regression analysis. The prevalences and mean intensities (+ one standard deviation) of infestation on each host species were, respectively: 100%; 86.4 + 94.6 in T. torquatus (n = 62); 100%; 20.9 + 9.3 in M. agilis (n = 7); 100%; 11.1 + 13.1 in M. macrorhyncha (n = 12); and 95.2%; 19.1 + 16.8 in C. littoralis (n = 21). Only for C. littoralis did body size significantly affect the intensity of infestation (r = 0.27, p = 0.02). For all lizard species, the body parts where chiggers occurred with the highest intensity were those of skin folds and joint regions.
A case of harvest-mite infestation acquired in the South Lakeland area is described in a 7-year-old boy and his immediate family. The characteristic papular urticarial lesions produced are extremely florid and may cause diagnostic problems when patients present in areas where the mite is uncommon. The life cycle of the harvest mite is discussed and recommendations for treatment given.
Larvae of the pest chigger mite Eutrombicula alfreddugesi Oudemans, 1910, exhibited a low repellent threshold for N,N-diethyl-3-methylbenzamide (deet) in a field setting. Use of a deet-based repellent significantly reduced chigger mite infestation. Efficacy of aerosol formulations was significantly diminished with 9% (AI) deet. E. alfreddugesi utilized both direct and indirect paths to infest the human body. Direct infestation led to the highest body region bite counts. Distribution of E. alfreddugesi bites over 15 regions of the human body fell into three zones of decreasing parasitism: the ankle/calf region (accessed through direct infestation); the groin, chest, back, armpits, and feet (accessed through indirect infestation); and the thighs, arms, buttocks, head, and neck, which were infrequently attacked or were unavailable to E. alfreddugesi.
Sera from Psoroptes ovis-infested calves were examined for 17 selected biochemical constituents to determine if P. ovis caused changes in any of these constituents. In order to recognize a scabies effect, there had to be a statistically significant (P less than or equal to 0.10) scabies exposure X time interaction and the changes in the biochemical constituents should have been correlated with the changes in the mite infestation. Five serum biochemical constituents fulfilled these criteria. Total protein, alpha-, beta-, and gamma-globulin were increased and total cholesterol was decreased at the peak of the scabies infestation. Precipitating antibodies to a P. ovis antigen were detected by immunodiffusion in some of the stored sera of the infested calves just after the peak of the infestation. Total protein, beta-, and gamma-globulin values were probably increased as a result of antibody production; alpha-globulin values were probably increased as a result of inflammation. As the scabies infestation declined, the mean values of all the above constituents from the infested calves, except cholesterol, began declining. Decreases in total cholesterol occurred, but they could not be entirely attributed to scabies. Examination of the serum biochemical constituents from a heavily infested calf that died during the test suggested that, in addition to antibody production and inflammation, kidney and liver damage may have occurred.
OBJECTIVE: To review the use of the oral antiparasitic ivermectin in the treatment of scabies, with an emphasis on its use in the elderly and in long-term care settings. DATA SOURCE: A MEDLINE/PUBMED search was conducted to identify pertinent studies, case reports, letters, and reviews in the English language. All articles published from 1980 to October 2003 were reviewed. Additional references were obtained from the bibliographies of these articles. STUDY SELECTION: All studies evaluating ivermectin in the context of scabies mite infestation. DATA SYNTHESIS: The semisynthetic macrocyclic lactone ivermectin has been available since the early 1980s as a broad-spectrum antiparasitic agent in animals and humans. This agent, which works by suppressing motor nerve conduction leading to parasite paralysis and death, was first used in ectoparasitic diseases (i.e., those caused by lice and mites) shortly after commercial introduction. A large body of literature, mainly uncontrolled case reports and series, has since evolved. However, these reports and results of the small number of placebo- and/or active-controlled studies have demonstrated the favorable response of both classic and crusted scabies to single- and multiple-dose oral ivermectin. Adverse reactions to the drug are uncommon, with the exception of a transient, new onset, or mild increase in existing pruritus soon after drug ingestion, which is thought to be a hypersensitivity reaction to dead mites and/or their products. CONCLUSION: Oral ivermectin may prove to be a time- and labor-saving alternative to topical scabicide treatments, especially in the institutional setting where labor shortages make the management of scabies outbreaks a true challenge. However, the use of this agent does not change the need to decontaminate the environment (clothing, bedding, bed clothes, and, in selected cases, floors and walls) in order to truncate an outbreak and prevent reinfestation.
Storage mites are important primary pests but present methods for trapping them are either rudimentary or have several limitations. These prevent effective early detection or reliable monitoring of mites in the food, animal feed and associated industries. The BT Trap is the first trap designed specifically for the detection and monitoring of mite infestation. This trap is made up of a mixed food base lure held in a robust adjustable housing. It is user friendly, requires an exposure period of only 4 days and can be used in a dusty environment. The performance of the BT Trap was evaluated in the laboratory and the mean minimal capture rate of mites was 62%. In a comparative field trial, this trap detected significantly more mites than the bait bag or the fishmeal trap. The trap's performance was also assessed in four different types of premises. These were premises engaged in the production of cereal based dry pet food, specialist animal feed, traditional cheese, and in the finished cereal section of a large transit storage warehouse. A total of 17 genera or species of storage and predatory mites was detected in these four premises, with at least seven species detected in each of these premises. This study confirms that the BT Trap was able to function under the rigours of use in the field. It has demonstrated its potential as a useful tool for early detection and monitoring of mites in production premises. It also provided information that was vital for improving existing mite control measures and in implementing effective management strategies.
In the district of Grafenau/Freyung (Bavaria, Germany), 266 specimens of small terrestrial mammals of 8 species were captured using live traps. From these mammals, Apodemus flavicollis (42.1%) and Clethrionomys glareolus (39.5%) were prevalent. All animals were tested for neutralizing antibodies to tick-borne encephalitis (TBE) virus and agglutinating antibodies to leptospirae. Seropositivity against TBE virus was 14.0% and against leptospirae 7.9%, respectively. Seropositivity to leptospirae appeared to be primarily to Leptospira grippotyphosa, less to Australis and occasionally to Javanica serovars. Only one A. flavicollis specimen was positive to both pathogens tested. The parasitocoenosis of trapped micromammals with ectoparasites consisted of 69.5% from ticks (mainly Ixodes ricinus, less from I. trianguliceps), 16.1% of mites (primarily Laelaps agilis) and 14.3% of fleas (mostly Ctenophthalmus agyrtes).
Human skin equivalents (HSEs) were used as a model to investigate interleukin (IL)-1 alpha and IL-1 beta secretions by keratinocytes stimulated by Sarcoptes scabiei (SS). SS mites burrowed into the stratum corneum when placed on the surface of cultured HSEs. Mites lived for 14 days. Mites and mite products induced cells in the HSEs to secrete IL-1 alpha and IL-1 beta within 16 hr. Scabies mites induced production of greater amounts of IL-1 alpha than IL-1 beta. Hepatocyte growth factor in the culture medium at 3 and 30 ng/ml upregulated the secretions of both IL-1 alpha and IL-1 beta by mite-infested skin equivalents, whereas 10 ng/ml of IL-6 upregulated production of only IL-1 beta. Therefore, these cytokines were important immunomodulating factors influencing keratinocyte secretion of IL-1 alpha and IL-1 beta in vitro. The results of this study provide the first evidence that keratinocytes (possibly fibroblasts) in the skin produce these cytokines in response to scabies mites or other ectoparasitic arthropods. Because IL-1 alpha and IL-1 beta are potent inducers of inflammation and keratinocytes are among the first effector cells to encounter scabies mites and their products, these cells may be key initiators of the inflammatory/immune reaction to scabies.
Previous studies of schoolchildren in Costa Rica have shown an asthma prevalence of 23% and a high level of sensitization, particularly to mite allergens. As a continuation of these studies, some 400 dust samples were collected from various places in Costa Rica, and parts of these were analyzed for specific mite and cockroach allergens, as well as for the number of mites and amount of guanine. Guanine was quantified by a diazo, as well as an HPLC method, which were found to be highly correlated. The concentrations of guanine by the diazo method, Der p 1, Der f 1, and the number of mites were higher in bed dust than in bedroom floor dust, and it was possible to quantify mite allergens and guanine in almost all bed-dust samples. The mean levels were 2-3 times higher than the proposed risk level for elicitation of symptoms in mite-sensitive asthmatics. Bed and bedroom floor dust contained more guanine and mite allergen in humid (> 2000 mm rain) than in drier places (P < 0.05), but the number of mites in bed and bedroom floor dust was higher in less humid places (P = 0.01). The guanine content in bedroom floor dust was higher in areas with a temperate climate than in areas with a warmer climate (P < 0.001, Bartlett's chi square [BCS]), as was the number of mites (P < 0.01, Kruskal-Wallis [KW], 0.04, BCS) and the Der p 1 concentration (P = 0.01, BCS; P = 0.02, KW). The Der f 1 concentration in bedroom floor dust was higher in a warmer than in a temperate climate (P < 0.001, BCS). More guanine and mites were found in urban than in rural bed dust (P = 0.03, KW). Dust samples from the metropolitan area (temperate climate) of Costa Rica contained higher levels of guanine (P < 0.01) and Der p 1 (P = 0.07) than the coastal areas, but very little Der f 1. In these samples, guanine and Der p 1 allergen were closely related, and 2 micrograms of the allergen was equivalent to 0.49 mg of guanine. Two-thirds of bed and floor samples collected on cotton filters contained Bla g 2 allergen at mean levels of 1.6 and 2.1 units/g dust, respectively. Cockroach allergen was, however, absent in all bed samples from the metropolitan area, but did occur in very high concentrations in the coastal bed dust samples collected with tighter polyester filters. In conclusion, the concentration of guanine and Der p 1 was very high in the bed dust of Costa Rican homes. Some factors, such as humidity, small houses for large families, and type of bedding, probably favored the heavy mite infestation, which is probably related to the widespread occurrence of bronchial asthma in this country.
A safe and practical home sanitation procedure for the removal of house dust mites (Dermatophagoides pteronyssinus) and their allergens is described. The severity of mite infestation was assessed with the use of the Acarex test, which measures the concentration of guanine in house dust, and all affected house textiles were then treated with an Acarosan product. The active ingredient of Acarosan is benzyl benzoate, which has been used as a scabicide for over 100 years. The results of several studies of Acarosan treatment were reviewed and it was concluded that use of the guanine test and Acarosan products allows many sensitized persons to control the concentration of house dust mite allergens in their homes.