PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “MITE INFESTATIONS”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources
PubMed1993

Prevalence of the causes of fleece derangement among sheep flocks in New South Wales.

An investigation of sheep flocks with unknown histories of fleece derangement, selected at random from the main sheep raising areas of New South Wales, showed that Psorergates ovis was present in 53 of the 177 flocks surveyed and in 162 of the 3495 sheep examined. Of the single causes of fleece derangement, the most prevalent was grass seed contamination (15.7%) followed by infestation with sheep body lice, Bovicola ovis, (14.7%) and infestation with itch mite (7.8%). The prevalence of fleece derangement was significantly higher on sheep in which lice were the only ectoparasites found than on those in which itch mites were the only ectoparasites present. The greatest prevalence of P ovis was in flocks in the Young, Yass, Mudgee and Tenterfield districts. In most affected flocks, more than one potential cause of fleece derangement was present. Itch mite infestation was more prevalent in flocks that received no treatment for ectoparasites than in those that had been treated in the year preceding the survey. Our results did not support a commonly held belief among farmers that arsenical compounds control infestations of itch mites more effectively than other types of pesticides. There was no significant difference in prevalence of fleece derangement between flocks treated with different pesticide groups and those that received no treatment, but mean fleece derangement score was significantly lower in sheep treated with organophosphates than in untreated sheep. Infestations of lice were significantly more prevalent in sheep from flocks treated with synthetic pyrethroids than from those treated with organophosphates or those that received no treatment.

Animals↗
PubMed1979

[On Cheyletiella infestation in domestic cats (author's transl)].

Two Persian cats kept in common, 3 months and 2 years old, presented a heavy infestation with Cheyletiella mites. The cats showed itching and loss of hair. The animals' owners suffered from severe itching and redish papulae, particularly on those parts of the body which frequently got in contact with the cats. After three treatments with Alugan powder (Hoechst) the cats were freed from the mite infestation. The owners' skin affection disappeared soon without any treatment. This is the first recovery of Cheyletiella mites on cats in Austria. The mites were identified as C. blakei, although obvious differences between the first description and our material were encountered. C. blakei could be primarily separated from C. parasitivorax according to the female tectum and the peritremata. Typically the sense organs on the genua of the first pair of legs are ovoid in shape. This feature, although morphologically variable, could be used as a diagnostic aid, if enough adult specimens are available.

Animals↗
PubMed2005

The role of varroa mites in infections of Kashmir bee virus (KBV) and deformed wing virus (DWV) in honey bees.

To determine the roles of varroa mites in activating or vectoring viral infections, we performed quantitative comparison of viral infections between bees with and without mites by dot blot analysis and enzyme-linked immunosorbent assay (ELISA). Under natural and artificial mite infestations, bee pupae contained significantly higher levels of Kashmir bee virus (KBV) and deformed wing virus (DWV) RNAs and KBV structural proteins than mite-free pupae. Moreover, in mite-infested bee pupae, DWV had amplified to extremely high titers with viral genomic RNA being clearly visible after separation of total bee RNA in agarose gels. Linear regression analysis has shown a positive correlation between the number of mites introduced and the levels of viral RNAs. The detection of viral RNAs in the nymph and adult mites underline the possible role of varroa in virus transmission. However, most groups of virus-free adult mites (9/12) were associated with bee pupae heavily infected by viruses, suggesting that the elevated viral titers in mite-infested pupae more likely resulted from activated viral replication. Based on these observations and our concurrent research demonstrating suppressed immune responses in bees infested with mites, we propose that parasitization by varroa suppresses the immunity of honey bees, leading to activation of persistent, latent viral infection.

Animals↗
PubMed2005

Safety of imidacloprid plus moxidectin topical solution applied to cats heavily infected with adult heartworms (Dirofilaria immitis).

A topically applied formulation containing 10% imidacloprid+1% moxidectin (Advocate/Advantage multi) has been developed for monthly application to cats for the prevention of feline heartworm (HW) disease caused by Dirofilaria immitis; and for the treatment and control of flea infestations, ear mite infestations, and intestinal nematode infections. A study model was designed to evaluate the safety of this product in cats harboring adult D. immitis infections. Eighty adult cats (40 males/40 females) were each inoculated with 60 third-stage D. immitis larvae on test day (TD) 1. On TD 243-245 echocardiographic imaging was performed on each cat to confirm and estimate the number of adult D. immitis residing in the cardiovascular system. A total of 35 cats were subsequently eligible for safety evaluation based on inclusion criteria. Four treatment groups were established and randomly selected for treatment: imidacloprid+moxidectin solution at the label dose (n=9) (group 1), imidacloprid+moxidectin solution at 5x the Iabel dose (n=9) (group 2), 6% selamectin topical solution (Revolution) at the label dose (positive control, n=8) (group 3), and topical treatment with placebo (negative control, n=9) (group 4). All cats were treated on TD 250. Treatments for groups 1, 3, and 4 were repeated on TDs 278 and 306. Group 2 cats were euthanized and examined for adult D. immitis on TD 288. All other cats were euthanized and examined for adult D. immitis on TD 334. No adverse events attributable to treatment with the test articles were observed during the study. The geometric mean numbers of adult D. immitis recovered at necropsy from treatment groups 1-4 were 2.9, 3.2., 4.0, and 2.7, respectively. There were no statistically significant differences in the comparison of adult D. immitis recovered at necropsy (ANOVA overall group effect P-value of 0.5356). The results of this study demonstrate that imidacloprid+moxidectin topical solution can be used safely in cats heavily infected with adult D. immitis.

Animals↗
PubMed2004

[Tyrophagus putrescentiae predating adult insects of Aedes aegypti and Aedes albopictus in laboratory].

The present study aimed at identifying a mite infesting a colony of Aedes aegypti and Ae. albopictus as well as investigating the source of infestation. The mite species was identified after it was mounted on slides in Hoyer's medium and examined under an optical microscope. It showed to be Tyrophagus putrescentiae. Fish and rabbit food samples were kept in an environmental chamber at 27 degrees C and 90% humidity for 21 days and were weekly examined. The presence of T. putrescentiae was only observed in rabbit food. It is assumed that T. putrescentiae had been introduced into the colonies through phoresy among guinea pigs, which were kept at the time near the insectary under favorable conditions for their development (28.7 degrees C, 72% humidity, photoperiod of 14L:10D hours).

Aedes↗
PubMed1995

House dust mite allergen content in two areas with large differences in relative humidity.

BACKGROUND: Striking differences in mite counts and mite-allergen levels have been documented between dwellings located at sea level and high altitude. Apart from relative humidity (RH), several other factors, ie, temperature, UV exposure, and altitude per se could account for this difference. OBJECTIVE: To evaluate whether RH by itself could influence mite infestation by comparing mite-allergens levels in two towns differing only with respect to RH. METHODS: We compared group I allergen content in two Moroccan towns: Casablanca, located on the seashore and Marrakech located at 1404 feet. Mean (+/- SD) RH in years 1990 and 1991 was 81.2 +/- 2.9% in Casablanca and 56.0 +/- 7.6% in Marrakech. Mean annual temperatures were 17.7 +/- 4.0 degrees C and 20.2 +/- 6.4 degrees C in Casablanca and Marrakech, respectively. In each town, 20 asymptomatic subjects agreed to participate in the study. Their mattresses were vacuum-cleaned for a standardized duration (2 min/m2). Mite allergen-content was evaluated using monoclonal antibodies and ELISA and results expressed as micrograms of group I (Der pI+Der f I) allergens per gram of dust (micrograms/g dust). RESULTS: Mean (+/- SD) group I allergen level was 8.3 +/- 8.8 micrograms/g in Casablanca and 0.6 +/- 0.6 micrograms/g dust in Marrakech, a difference that is highly significant (P = .001). In both areas, mean Der f I allergen level was low (0.7 +/- 0.5 and < 0.1 micrograms/g dust, in Casablanca and Marrakech, respectively). CONCLUSION: This study shows that house dust mite allergen content in households depends on RH rather than on temperature.

Allergens↗
PubMed2001

Recurrent infestation of the mastoid cavity with Caloglyphus berlesei: an occupational hazard.

Mite infestation of the ear is an unusual clinical problem that is easily cured with simple measures and recurrent infestation has not been reported till date. We present here a patient who developed recurrent infestation of otherwise healthy mastoid cavities with the storage mite Caloglyphus berlesei, secondary to occupational exposure. This kind of recurrent mite infestation of the ear has not been described before.

Agricultural Workers' Diseases↗
PubMed2004

Below-ground plant parts emit herbivore-induced volatiles: olfactory responses of a predatory mite to tulip bulbs infested by rust mites.

Although odour-mediated interactions among plants, spider mites and predatory mites have been extensively studied above-ground, belowground studies are in their infancy. In this paper, we investigate whether feeding by rust mites (Aceria tulipae) cause tulip bulbs to produce odours that attract predatory mites (Neoseiulus cucumeris). Since our aim was to demonstrate such odours and not their relevance under soil conditions, the experiments were carried out using a classic Y-tube olfactometer in which the predators moved on a Y-shaped wire in open air. We found that food-deprived female predators can discriminate between odours from infested bulbs and odours from uninfested bulbs or artificially wounded bulbs. No significant difference in attractiveness to predators was found between clean bulbs and bulbs either wounded 30 min or 3 h before the experiment. These results indicate that it may not be simply the wounding of the bulbs, but rather the feeding by rust mites, which causes the bulb to release odours that attract N. cucumeris. Since bulbs are belowground plant structures, the olfactometer results demonstrate the potential for odour-mediated interactions in the soil. However, their importance in the actual soil medium remains to be demonstrated.

Animals↗
PubMed2001

Resistance to Acarapis woodi by honey bees (Hymenoptera: Apidae): divergent selection and evaluation of selection progress.

Two generations of honey bees, Apis mellifera L., selected for resistance to tracheal mites, Acarapis woodi (Rennie), were produced from a foundation stock. The mite resistant lines had significantly low mite abundances and prevalences in each selected generation. The high mite-resistant lines of the first selected generation showed resistance equal to that of bees that had undergone natural selection from tracheal mite infestations for 3 yr in New York. Additionally, the high mite-resistant lines of the second selected generation and Buckfast bees had significantly lower mite abundances and prevalences than honey bees from control colonies which had never been exposed to tracheal mite infestation in Ontario. These results corroborate studies that have shown that honey bees possess genetic components for tracheal mite resistance that can be readily enhanced in a breeding program. The two methods used for evaluating relative resistance of honey bees to tracheal mites, a short-term bioassay and evaluation in field colonies, were positively correlated (rs = 0.64, P < 0.001).

Animals↗
PubMed2004

[Occurrence of a house-infesting tropical rat mite (Ornithonyssus bacoti) on murides and human beings in Munich: 3 case reports].

In Germany there is little information available about the distribution of the Tropical rat mite (Ornithonyssus bacoti) in rodents. A few case reports show that this hematophagous mite species may also cause dermatitis in man. All developmental stages are exclusively blood feeders. Three children (4, 11 and 15 years old) of a family, a 23-year-old medical student and a 17-year-old dental technician were attacked by the tropical rat mite. Prior to the consultation of our institute, the patients' conditions had been diagnosed as allergic dermatitis and treated by several antiphlogistic agents, however without success. The conclusive diagnosis of tropical rat mite dermatitis, was based on the identification of the arthropod O. bacoti in the flats of the patients (husbandry of gerbils, etc.) and in the dental practice. The diagnosis of rat mite dermatitis requires the detection of the parasite, which is more likely to be found in the environment of its host than on the host's skin itself.

Adolescent↗
PubMed2004

Ozone exposure triggers the emission of herbivore-induced plant volatiles, but does not disturb tritrophic signalling.

We evaluated the similarities between ozone-induced and mite-induced emission of volatile organic compounds (VOCs) from lima beans, and tested the response of the natural enemies of herbivores to these emissions using trophic system of two-spotted spider mites and predatory mites. The acute ozone-exposure and spider mite-infestation induced the emission of two homoterpenes, (E)-4,8-dimethyl-1,3,7-nonatriene and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene, and (Z)-3-hexenyl acetate. Only plants with spider mite-infestation emitted the monoterpene (E)-beta-ocimene. Predatory mites were equally attracted to ozone-exposed and unexposed plants, but discriminated between spider mite-infested and uninfested plants, when both were exposed to ozone. The similarities between ozone and herbivore-induced VOCs suggest that plant defence against phytotoxic ozone and the production of VOCs for attraction of the natural enemies of herbivores may have adaptive coevolution. However, the expected elevated ozone concentrations in future may not disturb tritrophic signalling, unless herbivore-induced VOCs are lost in the process of aerosol formation.

Air Pollutants↗
PubMed2001

Persistence and effectiveness of pyrethroids in plastic strips against Varroa jacobsoni (Acari: Varroidae) and mite resistance in a Mediterranean area.

An apiary trial was conducted in 1997 in Sardinia, Italy, to verify the effectiveness of fluvalinate in polyvinyl chloride strips and flumethrin in polyethylene strips against Varroa jacobsoni Oudemans. Two indices to evaluate the efficacy of the treatments were adopted: percentage change in mite infestation of worker-sealed brood cells considering only treated hives and percentage change in mite mortality, and the natural variation in mite populations recorded in control hives during the trial. All acaricide treatments reduced the level of mite infestation of both sealed brood and adult bees. However, their effectiveness was slightly reduced in comparison to previous studies because of mite resistance phenomena. Portions of polyethylene strips of flumethrin from treated hives were sampled weekly to determine acaricide persistence using gas chromatography. After 4 wk, a slight reduction (approximately 9%) of the active ingredient content was observed. A laboratory bioassay also was performed to establish the resistance of adult female mites to fluvalinate. Mites were sampled from the experimental apiary and from various Sardinian apiaries which had primarily been subjected to fluvalinate applications in plastic strips or wood inserts for years. Mite resistance varied from 0 to 96%, depending on the acaricide management adopted. The lowest resistance level occurred in an apiary where pyrethroids had never been used, whereas the highest level occurred in an apiary, with intensive use of fluvalinate in wood inserts.

Animals↗
PubMed2005

Impact of an ectoparasite on the immunity and pathology of an invertebrate: evidence for host immunosuppression and viral amplification.

Varroa mites (Varroa destructor) are ectoparasites of honey bees (Apis mellifera) and cause serious damage to bee colonies. The mechanism of how varroa mites kill honey bees remains unclear. We have addressed the effects of the mites on bee immunity and the replication of a picorna-like virus, the deformed wing virus (DWV). The expression of genes encoding three antimicrobial peptides (abaecin, defensin, and hymenoptaecin) and four immunity-related enzymes (phenol oxidase, glucose dehydrogenase, glucose oxidase, and lysozyme) were used as markers to measure the difference in the immune response. We have demonstrated an example of an ectoparasite immunosuppressing its invertebrate host with the evidence that parasitization significantly suppressed expression of these immunity-related genes. Given that ticks immunosuppress their vertebrate hosts, our finding indicates that immunosuppression of hosts may be a common phenomenon in the interaction and coevolution between ectoparasites and their vertebrate and invertebrate hosts. DWV viral titers were significantly negatively correlated with the expression levels of the immunity-related enzymes. All bees had detectable DWV. Mite-infested pupae developed into adults with either normal or deformed wings. All of the deformed-wing bees were greatly infected by DWV (approximately 10(6) times higher than varroa-infested but normal-winged bees). Injection with heat-killed bacteria dramatically promoted DWV titers (10(5) times in 10 h) in the mite-infested, normal-winged bees to levels similar to those found in mite-infested, deformed-wing bees. Varroa mites may cause the serious demise of honey bees by suppressing bee immunity and by boosting the amplification of DWV in bees exposed to microbes.

Analysis of Variance↗
PubMed1995

House-dust mite content in mattresses in relation to residential characteristics and symptoms in atopic and nonatopic children living in northern Norway.

The occurrence of house-dust mites (HDMs) was investigated in the mattresses of 19 children previously found to be skin prick test (SPT) positive to HDM and in 19 nonatopic children derived from an extensive survey of 424 schoolchildren, all living in northern Norway. Domestic mites were counted and identified microscopically. Mite counts ranging from 10 to 1800 mites per gram mattress dust were found in 10 of the 19 HDM-sensitized children compared to none in the control group, corresponding to an odds ratio of more than 20. Of the 540 domestic mites found, 70 were identified by species. Dermatophagoides pteronyssinus (Dpt) was the only HDM species identified (64 mites), while five were storage mites and one was a Tarsonemus species. Positive radioallergosorbent tests (RAST) to Dpt were demonstrated in 9/10 children with and in 5/9 without mite infestation compared to none in the control group. Elevated IgE levels were also found more frequently in children with mite-infested mattresses than in those without. IgE levels were within normal levels in all 19 children in the control group. Latent atopy was found in four children, three with and one without mite infestation. There was no correlation between the concentration of mites and the degree of sensitization. Poor ventilation, increased humidity, and water leak(s) were associated with the presence of domestic mites in mattresses. As HDM growth is highly dependent on humidity and microhabitat, it should be possible to avoid HDM exposure and allergy in this region.

Animals↗
PubMed1988

Sensitization of children in the Stockholm area to house dust mites.

Atopic sensitization of children in the Stockholm area to house dust mites (HDM) was investigated in a case-control study. Sixty children with and 60 without positive skin prick tests for HDM were matched for age and sex. HDM-sensitized children had previously more often lived in other areas known to be mite infested than the control children. Sensitization to mites was related to dampness in the homes, but no significant relationship was found to the type of residence, frequent visits to a summer house in the archipelago or parental smoking. Dust samples from mattresses of the children with the strongest positive reactions to mites in skin prick tests and the respective controls were subjected to an enzyme immunoassay, to measure the content of the major allergens of the Dermatophagoides (D.) species D. pterinyssinus, D. farinae and D. microceras. Mattress dust samples from the beds of HDM-sensitized children contained significantly higher HDM antigen concentrations than those from the beds of controls. Private houses contained significantly more HDM antigens than flats and 10 of 11 homes in which a dampness problem was recognized contained mite antigens. It is postulated that mite infestation is increasing in the area, energy-saving measures creating improved conditions for HDM survival.

Adolescent↗
PubMed1991

Control of Psoroptes cuniculi in captive white-tailed deer with ivermectin-treated corn.

Psoroptes cuniculi, the ear mite of domestic rabbits, was collected from captive white-tailed deer (Odocoileus virginianus). This is the first report of rabbit ear mite infestations in white-tailed deer in Oklahoma or Texas (USA). In addition to moderate infestations in their ears, two 4-yr-old bucks, two 3-yr-old does, and seven 4-yr-old does showed patchy areas of alopecia along the sides and brisket. Both bucks also had patchy areas of alopecia around the base of antlers. Ear mites were eradicated from all deer except from one doe by providing ivermectin-treated corn to the deer at a rate of 1,000 g (equivalent to 200 mcg/kg of ivermectin)/day/deer for several days. The ear mite infestation in the one doe was eradicated by intramuscularly injection with ivermectin at 400 mcg/kg. After treatment with the ivermectin and eradication of the mites, the alopecia improved and eventually was eliminated. The ivermectin-treated corn also controlled all internal nematode parasites in the deer.

Administration, Oral↗