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Scabies is considered one of the commonest dermatological diseases that has a global health burden. Current treatment with ivermectin (IVM) is insufficient and potential drug resistance was noticed. Moxidectin (MOX), with a better pharmacological profile may be a promising alternative. The efficacy of moxidectin against Sarcoptes scabiei was assessed both in vitro and in vivo in comparison with ivermectin. For the in vitro assay, both drugs were used in two concentrations (50 μg/ml and 100 μg/ml). For the in vivo assay, twenty rabbits infected with Sarcoptes scabiei were divided into three groups: untreated, moxidectin-treated and ivermectin-treated with the same dose of 0.3 mg/kg once. Another four rabbits were used as a normal control non-infected group. Treatment efficacy was evaluated by clinical assessment, parasitological evaluation and histopathological examination of skin samples using Hematoxylin and eosin and toluidine blue for mast cell staining. Immune response was also assessed by immunohistochemical staining of CD3 T cells in skin samples. Our results showed that moxidectin had a high efficacy (100%) in killing mites when used in both concentrations (50 μg/ml, 100 μg/ml) in the in vitro assay. Concerning the in vivo assay, on day 14 post-treatment, all MOX-treated rabbits were mite-free with full clinical cure by the end of the study (D21) showing (100%) reduction of mites count. Also, marked improvement in the epidermis with absence of mites in skin samples were shown. Poor clinical and parasitological improvements were noted in the ivermectin-treated rabbits, when given as a single dose with a percentage reduction (60.67%) in the 2nd week and progressive increase in lesions and mites count in the 3rd week post-treatment. Regarding the immune response, MOX-treated group showed mild infiltration with both mast cells and CD3 T cells in comparison to severe infiltration with both types of cells in the untreated and IVM-treated group. On conclusion, our results demonstrated that a single dose of MOX was more effective than IVM, supporting MOX as a valuable therapeutic approach for scabies therapy., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Introduction: The study of the interaction between the parasite, the vector and the mammalian hosts, including man, allows to understand the behavior of the leishmaniases., Objective: To determine the presence of Lutzomyia species and to detect the Leishmania infection in Didelphis marsupialis in an endemic area for visceral leishmaniasis., Materials and Methods: Phlebotomine fauna and individuals of D. marsupialis were collected with CDC and Tomahawk™ traps, respectively. The species of Lutzomyia were identified using the Young and Duncan key (1994). Ear and tail biopsies and blood samples from D. marsupialis were taken to identify the Leishmania species by amplifying a fragment of the gene associated with the 70 kD heat shock protein., Results: Seven Lutzomyia species were identified: Lu. evansi, Lu. gomezi, Lu. panamensis, Lu. dubitans, Lu. cayennensis cayennensis, Lu. rangeliana and Lu. trinidadensis. The first three species have epidemiological importance in Colombia because of their implications in the transmission of the Leishmania parasite. Sixty-five tissue samples from 19 D. marsupialis individuals were negative for Leishmania spp., Conclusions: The presence of the Lutzomyia species that have been identified as vectors for Leishmania inside and around houses in the village of El Bledo, in El Carmen de Bolívar represents a risk of infection. Furthermore, the presence of Lu. panamensis is reported for first time in El Carmen de Bolívar in Colombia. Although the lack of detection of Leishmania spp. in D. marsupialis samples may suggest that D. marsupialis does not play an important role in the transmission cycle of Leishmania in this region, it is necessary to carry out further longitudinal studies to confirm this hypothesis.

Currently, available treatment options for leishmaniasis are limited and unsatisfactory. In a previous study, a quinoline derivative (AMQ-j), exhibited a strong effect against Leishmania amazonensis and its antileishmanial activity was preliminarily associated with mitochondrial dysfunction. The present study further explores the antileishmanial effect of this compound against L. amazonensis, as well as determines the main cellular processes involved in the death of the parasite. Moreover, this study evaluated the in vivo effect of the AMQ-j in BALB/c mice experimentally infected by L. amazonensis. The results showed that the compound AMQ-j induces a set of morphological and biochemical features that could correlate with both autophagy-related and apoptosis-like processes, indicating intense mitochondrial swelling, a collapse of the mitochondrial membrane potential, an abnormal chromatin condensation, an externalization of phosphatidylserine, an accumulation of lipid bodies, a disorganization of cell cycle, a formation of autophagic vacuoles, and an increase of acidic compartments. Treatment with AMQ-j through an intralesional route was effective in reducing the parasite burden and size of the lesion. No significant increase in the serum levels of hepatic or renal damage toxicity markers was observed. These findings contribute to the understanding of the mode of action of quinoline derivatives involved in the death of Leishmania parasites and encourage new studies in other experimental models of Leishmania infection., (Copyright © 2018 Elsevier Inc. All rights reserved.)

In this study, we examined the prevalence, pathology, and epidemiology of tumors in free-ranging island foxes occurring on three islands in the California Channel Islands, USA. We found a remarkably high prevalence of ceruminous gland tumors in endangered foxes (Urocyon littoralis catalinae) occurring on Santa Catalina Island (SCA)--48.9% of the dead foxes examined from 2001-2008 had tumors in their ears, and tumors were found in 52.2% of randomly-selected mature (≥ 4 years) foxes captured in 2007-2008, representing one of the highest prevalences of tumors ever documented in a wildlife population. In contrast, no tumors were detected in foxes from San Nicolas Island or San Clemente Island, although ear mites (Otodectes cynotis), a predisposing factor for ceruminous gland tumors in dogs and cats, were highly prevalent on all three islands. On SCA, otitis externa secondary to ear mite infection was highly correlated with ceruminous gland hyperplasia (CGH), and tumors were significantly associated with the severity of CGH, ceruminous gland dysplasia, and age group (older foxes). We propose a conceptual model for the formation of ceruminous gland tumors in foxes on SCA that is based on persistent, ubiquitous infection with ear mites, and an innate, over exuberant inflammatory and hyperplastic response of SCA foxes to these mites. Foxes on SCA are now opportunistically treated with acaricides in an attempt to reduce mite infections and the morbidity and mortality associated with this highly prevalent tumor.

Cutaneous leishmaniasis is a sand fly-transmitted disease characterized by skin ulcers that carry significant scarring and social stigmatization. Over the past years, there has been cumulative evidence that immunity to specific sand fly salivary proteins confers a significant level of protection against leishmaniasis. In this study, we used an attenuated strain of Listeria monocytogenes as a vaccine expression system for LJM11, a sand fly salivary protein identified as a good vaccine candidate. We observed that mice were best protected against an intradermal needle challenge with Leishmania major and sand fly saliva when vaccinated intravenously. However, this protection was short-lived. Importantly, groups of vaccinated mice were protected long term when challenged with infected sand flies. Protection correlated with smaller lesion size, fewer scars, and better parasite control between 2 and 6 weeks postchallenge compared to the control group of mice vaccinated with the parent L. monocytogenes strain not expressing LJM11. Moreover, protection correlated with high numbers of CD4(+), gamma interferon-positive (IFN-γ(+)), tumor necrosis factor alpha-positive/negative (TNF-α(+/-)), interleukin-10-negative (IL-10(-)) cells and low numbers of CD4(+) IFN-γ(+/-) TNF-α(-) IL-10(+) T cells at 2 weeks postchallenge. Overall, our data indicate that delivery of LJM11 by Listeria is a promising vaccination strategy against cutaneous leishmaniasis inducing long-term protection against ulcer formation following a natural challenge with infected sand flies., (Copyright © 2014, American Society for Microbiology. All Rights Reserved.)

The entire range of the critically endangered Amargosa vole (Microtus californicus scirpensis) consists of less than 20 km(2) of riparian habitat in the Amargosa River drainage of the Mojave Desert in southern California. In September 2010, deformities on ears and chiggers on the ears and genitalia were detected, with some individuals so severely affected that they were missing ear pinnae altogether. Follow-up trapping was performed to document the presence of mites and mite-associated disease, and molecular characterization was performed on the mites. Of 151 Amargosa voles sampled from February to April of 2011, 60 (39.7%) voles had hard orange mites adhered to some part of their bodies, on ears of 46 (76.7%), on genitalia of 11 (18.3%), and near mammary tissue of 13 (21.7%) voles. Gross lesions were not detected on genitalia, but 47% of all individuals examined showed pinnal lesions and deformities, which included alopecia, swelling, marginal necrosis, and ulceration, as well as scarring, scabbing, and loss of pinna mass covering 25-100% of the pinnae. Biopsies revealed parakeratotic hyperkeratosis and acanthosis with diffuse neutrophilic exocytosis and dense necrotic granulocytes in the epidermis and superficial dermis associated with focal erosion and ulceration. In the underlying dermis, there were dense pleocellular inflammatory cell infiltrates composed primarily of necrotic granulocytes and multifocal hemorrhage. In some samples, mite mouthparts could be seen penetrating the superficial epidermis associated with focal necrosis, and mite fragments were found on the surface epidermis and within hair follicles. Microscopic examination of the mites documented that they were a larval trombiculid in the genus Neotrombicula with anatomical features that most closely resemble Neotrombicula microti, based on scutal shape, setation, and texture. PCR of 2 mite pools (each consisting of 3 mites from an individual animal) amplified 331 bp amplicons, which had 92-97% homology with the 18S rRNA gene of Leptotrombidium deliense, although coverage of Trombiculidae in GenBank is sparse. The severity and prevalence of lesions due to this chigger were atypical and distinct. Severe clinical trombiculiasis in this endangered species could negatively impact individual health and fitness.

Several reports have shown that cutaneous leishmaniasis lesions are painless, suggesting that Leishmania infection interferes with pain perception. Comparisons of inflammation-induced hyperalgesia between BALB/c and C57BL/6 mice have been little explored in the literature, and comparative data regarding nociception in leishmaniasis are non-existent. In susceptible BALB/c mice and resistant C57BL/6 mice that were intradermally inoculated with a low dose of Leishmania major in the ear, we investigated the variation in nociception over a 12-wk period post-infection and this variation's association with the structure of nerve fibres and the presence of endogenous cytokines that are classically considered hyper- or hypo-nociceptive. Infected BALB/c mice presented susceptibility and severe lesions. Infected C57BL/6 mice exhibited resistance and healing lesions. The immune response involved pro- and anti-inflammatory cytokine secretion, respectively. The infection-induced hypoalgesia in BALB/c mice after wks 9 was accompanied by decreased levels of IL-6 and IL-10 in ear tissue with intact nerves. C57BL/6 mice showed short-lived hyperalgesia in wks 2, which was related to increased local levels of IL-6, KC/CXCL-1, TNF-α and IL-10 and a decrease in nerve density. The increase in pro-inflammatory cytokine IL-6, KC/CXCL-1 and TNF-α levels during hyperalgesia suggested a role for these mediators in afferent nerve sensitisation, which was secondary to the inflammatory damage of nerve fibres stained by PGP 9.5. In contrast, the mechanisms of hypoalgesia may include the downregulation of cytokines, the preservation of the structure of nerve endings, and as yet uninvestigated unidentified differences in neurotransmitter release or a direct role of the parasites in the context of the progressive and permissive inflammatory response of BALB/c mice., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Leishmania vaccines that protect against needle challenge fail against the potency of a Leishmania-infected sand fly transmission. Here, we demonstrate that intradermal immunization of mice with 500 ng of the sand fly salivary recombinant protein LJM11 (rLJM11) from Lutzomyia longipalpis, in the absence of adjuvant, induces long-lasting immunity that results in ulcer-free protection against Leishmania major delivered by vector bites. This protection is antibody independent and abrogated by depletion of CD4(+) T cells. Two weeks after challenge, early induction of IFN-γ specifically to rLJM11 correlates to diminished parasite replication in protected animals. At this time point, Leishmania-specific induction of IFN-γ in these mice is low in comparison with its high level in non-protected controls. We hypothesize that early control of parasites in a T-cell helper type 1 environment induced by immunity to LJM11 permits the slow development of Leishmania-specific immunity in the absence of open ulcers. Leishmania-specific immunity observed 5 weeks after infection in rLJM11-immunized mice shows a twofold increase over controls in the percentage of IFN-γ-producing CD4(+) T cells. We propose LJM11 as an immunomodulator that drives an efficient and controlled protective immune response to a sand fly-transmitted Leishmania somewhat mimicking "leishmanization"-induced protective immunity but without its associated lesions.

Objective: This study has been planned to investigate some biological features of Hyalomma marginatum, which is one of the important vectors in the world and in our country., Methods: The study started with the adult H. marginatum which were collected from cattle in the field and attempts were made for these to be adapted to the laboratory by breeding in the laboratory throughout a generation. Unfed adult ticks and unfed larvae were bred on the rabbit ear while unfed nymphs were bred on the calf ear. The biologic development stages of this tick kind, except for sucking blood stage, passed in an incubator which was at a temperature of 28°C and 85% relative humidity, while the unfed active stages passed in an incubator which was at 18°C and 85% relative humidity to conserve for a long time., Results: Unfed females on rabbits were full and fell in approximately 15 days, began to ovulate 20.5 days later and ovulated for 16 days. The larvae which hatched out approximately 29 days later became active in 8.5 days. These larvae sucked blood from rabbits for 14.5 days and abandoned these animals as full nymphs. Unfed adult ticks, which existed as a result of these nymphs casting off their skin in approximately 26 days, became active by completing their cutinization in approximately 10 days., Conclusion: At the end of the study, it was determined that H. marginatum showed 2 different behaviors in rabbits. According to this, the total life cycle in the laboratory environment changed by between 97 and 182 days and lasted approximately 138.5 days.

Aural myiasis is a rare otolaryngological disease typically seen in poor hygienic conditions and medically disabled patients. We present a case of aural myiasis in a healthy woman who had no apparent risk factors for infestation and required extensive surgical intervention. We also discuss the literature of documented otolaryngological cases of myiasis and effective therapies. In our patient, symptoms of otalgia, otorrhea, and tinnitus resolved after multiple attempts at extraction resulted in successful eradication of larvae. The patient required tympanoplasty to reconstruct the damaged external and middle ear. Physicians should have a clinical suspicion of aural myiasis in patients with a travel history and an atypical presentation of acute otalgia and otorrhea.

Although 90% of clinical cases of American visceral leishmaniasis (AVL) occur in the northeastern region of Brazil, the incidence of cases in recent years has increased in southeastern states such as Minas Gerais (MG), where the disease has been reported in several cities, including Belo Horizonte, the state capital. Some studies have shown a strong correlation between the incidence of AVL and canine visceral leishmaniasis (CVL) in Belo Horizonte. A study of 108 dogs with parasite Leishmania chagasi detected by immuno-histochemistry in healthy ear skin was obtained from two distinct geographical areas: 55 from a metropolitan area of the municipality (Santa Luzia, MG) and 53 dogs from a central area of Belo Horizonte. In parallel, a group of 10 beagles were experimentally infected with L. chagasi. Considering the clinical aspects of all naturally infected dogs, symptomatic dogs were more frequent than asymptomatic ones, especially animals from the metropolitan area compared with the central area (79.6% and 20.3%, respectively). A chronic exudate was observed in the ear of 51 out of 55 dogs naturally infected from the metropolitan area (92.7%) and 45 out of 53 dogs naturally infected from the central area (84.9%). Importantly, asymptomatic dogs from the central area harbor more parasites in the skin than the asymptomatic ones from the metropolitan area. In addition, a profound difference was noted in the intensity of the inflammatory reaction and parasite load in the skin of experimental infected dogs.

We describe the relationship between lesion outcome and histopathological hallmarks in susceptible (BALB/c) and resistant (C57BL/6 and IL-4-deficient BALB/c) mouse strains over the course of a 12-week-infection with Leishmania major in the ear. The infiltration of mononuclear cells and polymorphonuclear cells occurred within 6 h and mononuclear cells predominated one week post-infection. Permissive intracellular growth of the pathogen was associated with non-healing lesions. In contrast, tissue damage and clearance of the parasite was observed in healing lesions and was associated with inducible nitric oxide synthase expression. The identification of the structural components of tissue reaction to the parasite in this study furthers our understanding of subjacent immune effector mechanisms.

An 87-year-old man had a longstanding untreated large basosquamous carcinoma on his right ear. He was admitted to the emergency department at our hospital. A large portion of the auricle had perished, together with part of the tumour. Surgery was planned but two days before, the patient complained of an irritating loud noise in his ear. We discovered this was caused by maggots in his external acoustic meatus: myiasis. Dozens of maggots were removed. A striking finding was that the smell of the wound had disappeared and that the wound was much cleaner, with a reddish aspect and less necrosis. The surgical procedure was uneventful. Larval therapy has been known for centuries. In recent years it has gained renewed interest as it may enhance wound debridement, wound disinfection, and may promote wound healing.

Leishmania tropica is the causative agent of Old World anthroponotic cutaneous leishmaniasis, which is characterized by lesions that take an extended period of time to heal, often resulting in disfiguring scars, and are more refractory to treatment than leishmaniasis caused by Leishmania major. Immunologic studies involving experimental animal models of L. tropica infection are virtually nonexistent. In the current study, infectious-stage L. tropica were used to establish dermal infections in C57BL/6 and BALB/c mice. In both strains, the lesions were slow to develop and showed minimal pathology. They nonetheless contained a stable number of between 10(4) and 10(5) parasites for over 1 year, which were efficiently picked up by a natural sand fly vector, Phlebotomus sergenti. Control of parasite growth depended on the development of a Th1 response, as C57BL/6 mice genetically deficient in Th1 cytokines and BALB/c mice treated with Abs to IFN-gamma harbored significantly more parasites. By contrast, IL-10-deficient mice harbored significantly fewer parasites throughout the infection. To further study the immunologic mechanisms that may prevent efficient clearance of the parasites, IL-10 and TGF-beta signaling were abrogated during the chronic phase of infection in wild-type C57BL/6 mice. Distinct from chronic L. major infection, IL-10 blockade alone had no effect on L. tropica, but required simultaneous treatment with anti-TGF-beta Abs to promote efficient parasite clearance from the infection site. Thus, chronic infection with L. tropica appears to be established via multiple suppressive factors, which together maintain the host as a long-term reservoir of infection for vector sand flies.

Several clinical reports have shown promising, but not optimal, results from photodynamic therapy with delta-aminolevulinic acid-derived protoporphyrin IX, termed ALA-PDT, as a treatment for cutaneous leishmaniasis (CL). Therefore, understanding the basis of the phototoxic response of Leishmania parasites to ALA-PDT may be critical for optimization. We report here both in vitro and in vivo mechanistic studies of ALA-PDT against CL. Following in vitro co-incubation of Leishmania major with 0.1 microM ALA, the PpIX concentration remained at the basal level, whereas after co-incubation with 0.1 microM exogenous PpIX, the PpIX level was 100-fold higher. No differences in ALA-derived PpIX levels were detected between Leishmania-infected and non-infected J774.2 cells, and PDT did not demonstrate any parasiticidal effects on amastigotes. In contrast, in vivo topical ALA-PDT, performed on a murine CL model, resulted in significant reductions of the parasite loads and vigorous tissue destruction. After ALA-PDT, a dramatically decreased percentage of macrophages and increased levels of interleukin-6 were observed in the infected skin. The clinical outcome observed with ALA-PDT is likely the result of unspecific tissue destruction accompanied by depopulation of macrophages rather than direct killing of parasites.

The acaricidal activity of Eugenia caryophyllata essential oil was evaluated in vitro and in vivo on Psoroptes cuniculi, a mange mite. In vitro, different concentrations of the oil were tested and the observed mites mortality was compared with that observed in untreated and treated (Acacerulen R) controls. In vivo, six P. cuniculi infected rabbits were topically treated with the oil diluted at 2.5% and compared with untreated and treated control groups of six rabbits each. In vitro, up to the concentration of 0.10% the oil gave highly significant (P<0.01) percentages of mite mortality respect to the untreated controls, but only up to 0.16% it showed the same efficacy of Acacerulen R. In vivo, the treatment with the essential oil cured all infested rabbits and no statistical differences were observed respect to the treated control group. The untreated rabbits remained infested.

We report three cases of human otomyiasis observed in rural Moroccan children. Myiasis of external orifices usually occurs from neglected chronic lesions of the patients with poor personal hygiene. The parasitologic identification revealed Wohlfahrtia magnifica. Wohlfahrtiosis is common myiasis of sheep and goats in Mediterranean basin. Through this paper we underline the epidemiological, pathogenic, clinical and therapeutic aspects of this parasitosis.

The aim of the present study was to investigate the in vitro and in vivo acaricidal effects of an essential oil of Cinnamomum zeylanicun leaves on Psoroptes cuniculi, a mange mite. In vitro, 2.5 ml of the essential oil diluted at different concentrations, from 10% to 0.03%, in paraffin oil were added to Petri dishes containing all motile stages of P. cuniculi. Mites mortality observed in these dishes was compared with that observed in untreated and treated (AcaCerulen R) control plates. In vivo, one group of six P. cuniculi infected rabbits was topically treated two times at seven days interval with two ml of the essential oil at the concentration of 2.5% in paraffin oil and compared with untreated and treated (AcaCerulen R) control groups of six rabbits each. After 24 h of contact, all concentrations of essential oil between 0.10 and 10% showed a good in vitro acaricidal efficacy if compared with the untreated controls (p<0.01), but only the concentrations between 0.16 and 10% turned out as active as the drug. In vivo, the treatment with the essential oil cured all infested rabbits and no statistical differences were observed with the treated control group.

A patient with an ulcerated cutaneous leishmaniasis of the pinna had suppurative otochondritis after a first unsuccessful course of treatment with meglumine antimoniate. Although the Leishmania ulceration healed after a second course of meglumine antimoniate, and despite three oral dicloxacillin or pristinamycin courses, the otochondritis extended and an abscess developed. Pus from the abscess revealed a pure culture of Pseudomonas aeruginosa. Five days of oral ciprofloxacin plus rifampin led to a marked improvement. The P. aeruginosa isolate was sensitive to ciprofloxacin but fully resistant to rifampin. Healing with minimal mutilation was obtained at the end of a six-week course of multiple antibiotic therapy. Pseudomonas aeruginosa otochondritis was a co-factor of cartilage mutilation in this patient. Thus, infection with P. aeruginosa should be promptly treated when present in tender cutaneous or mucosal leishmaniasis lesions near cartilaginous areas.

Samples of ear scrapings, serum and diaphragmatic muscle were collected from 271 fattening pigs at the slaughterhouse. The scrapings were examined for the presence of mites, and tests for specific antibodies to Sarcoptes scabiei var suis in the serum and meat juice were made with an experimental ELISA. The cut-off value for the meat-juice ELISA was estimated at an optical density of 0.5 by receiver operating characteristic curve analysis, on the basis of the cut-off value for the serum ELISA of 0.4. The results of the three tests were used in a Bayesian model to estimate the characteristics of each test. The specificity of the tests of the ear scrapings was considered to be 1 and their sensitivity was estimated by Bayesian analysis to be 0.86, with a 95 per cent confidence interval (CI) of 0.73 to 0.99. The sensitivity of the meat juice ELISA (0.71, 95 per cent CI 0.6 to 0.8) and its specificity (0.77, 95 per cent CI 0.66 to 0.89) were comparable with the sensitivity (0.73, 95 per cent CI 0.6 to 0.8) and specificity (0.81, 95 per cent CI 0.69 to 0.95) of the serum ELISA.

Many cases of myiasis have been reported in Malaysia. This is the second reported case of auricular myiasis caused by Chrysomya bezziana. The patient was a 41-year-old, mentally retarded, Orang Asli man. He was brought to the clinic by his mother with a complaint of pain and bleeding in his right ear for 3 days. On examination, blood and multiple maggots were seen packed in the external auditory canal of the right ear. A total of 39 live maggots were removed and maintained until they developed into 3rd instar larvae, which were later processed and identified as Chrysomya bezziana. The patient was discharged with amoxicillin 500 mg three times a day for 1 week.

Leishmania spp. cause a broad spectrum of diseases collectively known as leishmaniasis. Leishmania braziliensis is the main etiological agent of American cutaneous leishmaniasis (ACL) and mucocutaneous leishmaniasis. In the present study, we have developed an experimental model of infection that closely resembles ACL caused by L. braziliensis. In order to do so, BALB/c mice were infected in the ear dermis with 10(5) parasites and distinct aspects of the infection were evaluated. Following inoculation, parasite expansion in the ear dermis was accompanied by the development of an ulcerated dermal lesion which healed spontaneously, as seen by the presence of a scar. Histological analysis of infected ears showed the presence of a mixed inflammatory infiltrate consisting of both mononuclear and polymorphonuclear cells. In draining lymph nodes, parasite replication was detected throughout the infection. In vitro restimulation of draining lymph node cells followed by intracellular staining showed an up-regulation in the production of gamma interferon (IFN-gamma) and in the frequency of IFN-gamma-secreting CD4(+) and CD8(+) T cells. Reverse transcription-PCR of ears and draining lymph node cells showed the expression of CC chemokines. The dermal model of infection with L. braziliensis herein is able to reproduce aspects of the natural infection, such as the presence of an ulcerated lesion, parasite dissemination to lymphoid areas, and the development of a Th1-type immune response. These results indicate that this model shall be useful to address questions related to the concomitant immunity to reinfection and parasite persistence leading to mucocutaneous leishmaniasis.

Experimental Leishmania major infection in mice has been of immense interest because it was among the first models to demonstrate the importance of the Th1/Th2 balance to infection outcome in vivo. However, the Th2 polarization that promotes the development of nonhealing cutaneous lesions in BALB/c mice has failed to adequately explain the mechanisms underlying nonhealing forms of leishmaniasis in humans. We have studied a L. major strain from a patient with nonhealing lesions that also produces nonhealing lesions with ulcerations and high parasite burden in conventionally resistant C57BL/6 mice. Surprisingly, these mice develop a strong, polarized, and sustained Th1 response, as evidenced by high levels of IFN-gamma produced by Leishmania-specific cells in the draining lymph node and in the ear lesion, and an absence of IL-4 or IL-13. The parasites fail to be effectively cleared despite high level induction of inducible NO synthase in the lesion, and despite their sensitivity to killing by IFN-gamma-activated macrophages in vitro. Infection of IL-10(-/-) mice, blockade of the IL-10R, or depletion of CD25(+) cells during the chronic phase promotes parasite killing, indicating that IL-10 and regulatory T cells play a role in rendering the Th1 responses ineffective at controlling infection in the skin. Mice with nonhealing primary lesions are nonetheless resistant to reinfection in the other ear. We suggest that nonhealing infections in animal models that are explained not by aberrant Th2 development, but by overactivation of homeostatic pathways designed to control inflammation, provide better models to understand nonhealing or reactivation forms of leishmaniasis in humans.

Objective: To investigate the distribution of demodex folliculorum and demodex breuis infection in the external auditory meatus of college students, that may to guide prevention and treatment., Method: Ma F. Method was applied to investigate the external auditory meatus secretion demodex folliculorum and demodex breuis infection on 613 college students., Result: Positive date were 11.58%, it was indifferent in fame or male. Cases of the external auditory meatus demodex folliculorum and demodex breuis infection complained constant scratching anitch (67.6%), that was more in positive cases than in negative case., Conclusion: Scratching anitch in external auditory meatus may have close relationship with demodex folliculorum and demodex breuis infection.

Objective: To evaluate the efficacy and safety of topical administration of selamectin in rabbits naturally infested with Psoroptes cuniculi., Design: Randomized controlled trial., Animals: 48 mixed-breed domestic rabbits with active P. cuniculi mite populations and clinical ear lesions., Procedures: Rabbits were randomly allocated to 1 of 6 treatment groups. On day 0, rabbits in groups 1 and 2 were given vehicle, rabbits in groups 3 and 4 were given selamectin at a dose of 6 mg/kg (2.7 mg/lb), and rabbits in groups 5 and 6 were given selamectin at a dose of 18 mg/kg (8.2 mg/lb). On day 28, rabbits in groups 2, 4, and 6 were given a second dose of vehicle or selamectin. Otoscopic examinations were performed and ear lesion size was measured weekly for 8 weeks. Quantitative viable mite counts were performed on day 56., Results: On days 7 through 56, lesion sizes for all selamectin-treated groups were significantly lower than sizes for control groups; there were no significant differences in lesion sizes among selamectin-treated groups. All rabbits in the 2 control groups had viable adult P. cuniculi mites for the duration of the study, as determined by otoscopic examination, whereas all rabbits in the 4 selamectin-treated groups were free from P. cuniculi mites on days 7 through 56. No adverse reactions associated with selamectin treatment were observed., Conclusions and Clinical Relevance: Results suggest that topical application of selamectin at a dose of 6 or 18 mg/kg can completely eliminate mites from rabbits naturally infested with P. cuniculi.

Mites collected from the auditory canal of Cebus apella (capuchin monkey), family Cebidae, were identified as Fonsecalges johnjadini (Psoroptidae, Cebalginae). It is the first record of this parasite from this monkey. This paper emphasizes the importance of clinical and anatomopathological examinations for parasitic diagnosis in wild animals.

The second internal transcribed spacer of the rRNA gene was characterised in 15 Psoroptes isolates collected from the ears or bodies of rabbits, goats, sheep and cattle originating from four continents. Morphologically, the isolates were differentiated as Psoroptes cuniculi, Psoroptes ovis and Psoroptes cervinus. Genotypically, the isolates were highly homogeneous, except for the existence of different rDNA classes. In view of previous phenotypic data, a possible conspecificity of these species is proposed.

Studies were done on delivery of Plasmodium yoelii sporozoites by Anopheles stephensi into the skin of BALB/C mice. When infected mosquitoes fed on a portion of the ear, 81% of these positive control mice developed parasitemia. When the fed-upon site was excised immediately or 5 min postfeeding, a highly significant, smaller percentage of these experimental mice developed parasitemia. When the delay in removal of mosquito-bitten tissue was extended to 15 min, no significant difference was found between this group and positive control mice. These findings show that mosquito-injected sporozoites tend to remain at the bite site for at least 5 min after the mosquito bite. By approximately 15 min, the first wave of migrating sporozoites has left the bite site and moved into the general circulation. These findings have implications concerning possible host obstruction of sporozoite migration in skin by either anti-sporozoite antibodies or by a cutaneous hypersensitivity reaction to mosquito bite.

Psoroptes sp. mites and tan crusty lesions were detected in the ears of a captive Stone sheep (Ovis dalli stonei) in April 1996, after contact with infected captive Rocky Mountain bighorn sheep (Ovis canadensis canadensis). Psoroptes spp. have not been detected in free-ranging ungulates in Canada or Alaska (USA). This is the first report of Psoroptes sp. in Stone sheep, indicating their susceptibility to infection.

Two clinical cases of cutaneous leishmaniasis of the outer ear in children are reported. The patients were treated successfully with a single intralesional injection of N-methylglucamine antimonate (Glucantime). Aetiopathogenesis, epidemiology, clinical manifestations, diagnosis, and treatment of cutaneous leishmaniasis are discussed.

Severe muscle cramping not associated with exercise was observed in 5 horses. Focal muscle groups in various regions underwent intermittent visible contraction. Intermittent prolapse of the third eyelid, sweating, pawing, muscle tremors, and muscle fasciculations also were observed. Clinical signs often were misconstrued as signs of colic. Percussion of muscle induced contraction of muscle groups. Concentrations of serum electrolytes and the acid-base balance were within reference limits, but activities of creatine kinase and aspartate transaminase were moderately high. Muscle biopsy revealed no abnormalities except for a few necrotic muscle fibers undergoing phagocytosis. Electromyography of 1 horse was suggestive of increased motor unit activity. All horses had Otobius megnini (ear tick) infestations and had recurrence of signs until treatment was initiated for ear ticks.

The microfiladermia of Monanema martini was studied in two natural murid hosts, Lemniscomys striatus and Arvicanthis niloticus, with 137 and 39 rodents respectively inoculated once, twice or several times. Microfilarial densities (mf/mm2) were measured at the ear pinna every three months. Almost all the rodents developed a microfiladermia. When L. striatus rodents were inoculated once with 30, 80, or 400 infective larvae, microfiladermia increased (peaks of 108, 148, 174 mf/mm2 respectively, at six to nine months p.i.); this fits with the fact that, in this filaria-host pair, the number of adult filariae is proportional to the number of inoculated larvae, and remains at a constant level for more than eight months. Nevertheless microfiladermia was limited, especially during the peak, showing the complexity of its regulatory mechanisms. Several low doses over one year, resulting in 145 L3, increased the microfiladermia at the same level than one dose of 400 larvae; the recovery rate of the larvae was reduced but the total number of filariae recovered was increased. A. niloticus, from which the filarial strain originates, showed a much lower microfiladermia than L. striatus (7 mf/mm2 with 80 larvae, at six months p.i.). This was due to a smaller recovery rate of the infective larvae in this host and, overall, to a reduced fertility of the female worms and a shorter lifetime of adult filariae. However, repeated inoculations increased the microfiladermia (32 mf/mm2), due to the constant presence of small numbers of young filariae producing microfilariae. It is to be noted that the two biological systems presented by M. martini in L. striatus and A. niloticus correspond to the two types of ocular pathology described in a recent opthalmological study, chorioretinal atrophy and keratitis respectively.

Histo-pathological analysis of the eyes, ears, skin and associated skeletal muscles of the back of 14 animals infected with a filarioid worm with dermal microfilariae, Cercopithifilaria johnstoni: seven Rattus fuscipes, of which four were naturally infected, two marsupials, Perameles nasuta and Isodon macrourus, and five R. norvegicus. This filarioid nematode induces skin and eye lesions in all the infected animals. These lesions are similar to those described earlier with other filarioid species with dermal microfilariae, such as Monanema martini and Onchocerca volvulus; the pathogeny is similar: microfilariae live inside the lymphatic vessels and their accidental exit gives rise to a localized inflammatory reaction leading to fibrosis. C. johnstoni is particularly interesting because it may be adapted to the laboratory rat, and because the ocular lesions are severe.

Subclinical psoroptic otocariasis associated with Psoroptes cuniculi (Delafond) was diagnosed in four out of ten herds of sheep. Transmission of mites between sheep and goats and vice versa was detected in herds kept on the same pastures for over 2 years. Flushing the ear canals of sheep and goats with approximately 50 ml of water appeared to be more efficient than swabbing or otoscopic examination for diagnosis and/or mite collection.

When 400 micrograms ivermectin/kg was administered subcutaneously to rabbits infected with the ear mite Psoroptes cuniculi it significantly reduced the clinical score, and when 500 micrograms ivermectin/kg was administered subcutaneously to guinea pigs with mange due to Trixacaurus caviae it resulted in a clinical cure. In rabbits a subcutaneous dose of 400 micrograms/kg produced high and sustained concentrations of ivermectin in the tissues and body fluids for at least 13 days and its rate of depletion from tissues was similar to that observed in sheep and rats. The mean (+/- sem) maximum concentration in plasma was 42.0 +/- 9.7 ng/ml 37.2 +/- 5.0 hours after administration and the area under the concentration-time curve was 3543 +/- 580 ng/ml hours. After the administration of 500 micrograms ivermectin/kg to guinea pigs orally, subcutaneously or topically the drug could be detected in the plasma only after subcutaneous administration. The mean concentration 72 hours after its administration to four guinea pigs was 0.7 +/- 0.3 ng/ml.

We examined the efficacy of ivermectin in the control of ear mites (Psoroptes cuniculi) in rabbits. The study involved 40 female and 35 male rabbits that were known to be naturally infested with ear mites. After a period of acclimation to the animal care facilities, the rabbits were ranked on the visual appearance of any ear lesion and the number of mites on glycerin-dipped ear swabs. The rabbits were then randomly assigned to 1 of 4 treatment groups; vehicle only (group 1), 50 micrograms of ivermectin/kg of body weight (group 2), 100 micrograms of ivermectin/kg (group 3) and 200 micrograms of ivermectin/kg (group 4). The rabbits were treated by SC injections on day 0 and day 14 of the trial; thus, the total dose of ivermectin given to groups 1 through 4, was 0, 100, 200, or 400 micrograms/kg, respectively. The study ended 2 weeks after the last treatment. Ear lesions of the treated rabbits improved significantly (P less than 0.001). By 28 days after the first treatment, the mean number of mites on the ear swabs (both ears) was 57.5 for untreated rabbits and 9.1, 0.5, and 2.5, respectively, for rabbits in groups 2, 3, and 4. The mean number of mites recovered from the ears of the untreated rabbits at necropsy was 24,297. For groups 2, 3, and 4, the mean number of mites recovered from the ears was 5,352, 96, and 96, respectively. The efficacy of treatment with a total dose of 100 micrograms/kg was 77.96%, with 200 micrograms/kg was 99.61%, and for 400 micrograms/kg was 99.61%.

Significant differences in the distribution of brown paralysis ticks on various age classes of Angora goats were recorded. In kids, most (greater than 98%) of the ticks attached to the head and ears, whereas in older groups, in addition to the ears, a high proportion (greater than 20%) of ticks also attached to the ventral side of the neck. There were significant differences in the mean infestation densities of both male and female R. punctatus in kids and older animals. These differences were, however, only significant for the first two sample dates involving kids, and are probably related to behavioural attributes of the kids which enhance tick/host contact. Newly born Angora goat kids are considered a high-risk group with regard to paralysis caused by the brown paralysis tick. Methods of avoiding mortality amongst kids are suggested.