Crusted scabies (sarcoptic mange) in four cats due to Sarcoptes scabiei infestation

Feline sarcoptic mange in Poland: A case series of three cats

BACKGROUND

Sarcoptic mange is rare in cats. The main symptoms reported in cases of feline sarcoptic mange include crusty lesions and pruritus, although these may vary in severity among individuals.

OBJECTIVES

This report describes three cats infested with Sarcoptes scabiei, all presenting with pruritus and excoriation.

METHODS

The diagnosis was confirmed by microscopic observation of skin scrape samples.

RESULTS

All three cats were treated successfully using moxidectin and imidacloprid, selamectin and ivermectin, respectively.

CONCLUSIONS

The clinical presentation of feline scabies appears to be more variable in cats than in dogs. Infestation with S. scabiei should be considered a differential diagnosis for cats presenting with pruritic inflammatory skin disease.

Sarcoptic mange in Felidae: does Sarcoptes scabiei var. felis exist? A first molecular study

Domestic and wild felids are considered suitable hosts for the parasitic mite Sarcoptes scabiei, and sarcoptic mange is reported in several felid species in the scientific literature. However, the historic classification of Sarcoptes mites into host-specific varieties does not include S. scabiei var. felis. It is unclear whether sarcoptic mange transmission in felids involves canids, other sympatric species, or exclusively felids. This study aimed to characterize the genetic structure of S. scabiei mites from domestic cats (Felis catus) and Eurasian lynx (Lynx lynx carpathicus), comparing them with Sarcoptes mites from sympatric domestic and wild carnivores. Ten Sarcoptes microsatellite markers were used to genotype 81 mites obtained from skin scrapings of 36 carnivores: 4 domestic cats, one dog (Canis lupus familiaris), 4 Eurasian lynx, 23 red foxes (Vulpes vulpes), and 4 grey wolves (Canis lupus lupus) from either Italy, Switzerland or France. Two genetic clusters of S. scabiei with a geographical distribution pattern were detected: mites from cats originating from Central Italy clustered with those from sympatric wolves. In contrast, all the other mites from Switzerland, France and Northern Italy clustered together. These results strengthen the previously advanced hypothesis that genetic variants of S. scabiei have a predominant geographic-related distribution with cryptic transmission patterns. These patterns may rely on the interactions between different hosts living in the same ecological niche rather than a simple infection among hosts belonging to the same taxon, reinforcing the idea that the S. scabiei historic classification into "var" might have little ongoing relevance.

Artificial Infestation of Sarcoptes scabiei (Acari: Sarcoptidae) in Rabbits Exhibits Progressive Pathological Changes, Apoptosis, and Keratinization in the Skin

Sarcoptes scabiei (S. scabiei) is an ectoparasite that can infest humans and 150 mammalian host species, primarily causing pruritus, crust, and alopecia. However, neither the pathological process of host skin under S. scabiei infection nor the mechanism of S. scabiei infection in regulating apoptosis and keratinization of host skin has been studied yet. In this study, a total of 56 rabbits were artificially infested with S. scabiei, and the skin samples were collected at seven different time points, including 6 h, 12 h, day 1, day 3, 1 week, 4 weeks, and 8 weeks, whereas a group of eight rabbits served as controls. We measured epidermal thickness by H&E staining, observed the skin ultrastructure by electron microscopy, and detected the degree of skin apoptosis by TUNEL staining. The level of transcription of genes related to apoptosis and keratinization was detected by quantitative real-time PCR (qRT-PCR), and the level of Bcl-2 protein expression was further detected using immunohistochemistry. Our results showed that, with increased infestation time, the epidermal layer of the rabbit skin exhibited significant thickening and keratinization, swollen mitochondria in the epidermal cells, and increased skin apoptosis. The level of caspase-1, 3, 8, 10, 14, and Bcl-2 mRNA expression was increased, whereas the level of keratin 1 and 5 was decreased after S. scabiei infestation. In conclusion, S. scabiei infestation causes thickening of the epidermis, which may be related to apoptosis-induced proliferation and skin keratinization.

An Uncommon and Severe Clinical Case of Sarcoptes scabiei Infestation in a Cat

The burrowing mite Sarcoptes scabiei causes sarcoptic mange in dogs and other mammals, including humans. Despite S. scabiei infests several animals, little is known about the epidemiology, clinical features, and treatment of sarcoptic mange in cats. A few reports have shown that clinical signs of S. scabiei infestation in cats may vary from non-pruritic crusted lesions to itchy and mild lesions, while severe signs are very infrequent. The present report describes a severe case of S. scabiei infestation in a stray cat from Italy, characterized by bilateral alopecia, diffuse and multifocal hyperpigmented, crusted, erythematous, scaled, and exfoliated lesions. The cat was FIV-positive and also infected by the cestode Dipylidium caninum. After treatment with a broad-spectrum parasiticide and an antibiotic, the cat showed an almost complete clinical recovery in 4 weeks. Unfortunately, no further clinical examinations were performed due to the lack of compliance of the owner and to the death of the cat for causes unrelated to sarcoptic mange. This clinical case indicates that under certain circumstances, S. scabiei can reproduce and cause severe clinical signs in cats which are usually considered non-permissive hosts for this mite, and in which the disease is usually self-limiting. Clinic-pathological, epidemiological, and zoonotic implications are discussed.

Zoonotic Episodes of Scabies: A Global Overview

Zoonotic scabies (ZS), also referred to as “pseudoscabies”, is considered a self-limiting disease with a short incubation period and transient clinical skin signs. It is commonly thought that Sarcoptes scabiei mites from animals are unable to successfully reproduce and persist on human skin; however, several ZS case reports have mentioned the persistence of symptoms and occasionally mites for weeks. The aim of this review was to collect and organize the sparse literature explicitly referring to S. scabiei zoonotic transmission, focusing on the source of the outbreak, the circumstances leading to the transmission of the parasite, the diagnosis including the identification of the Sarcoptes “strain” involved, and the applied treatments. A total of 46 articles, one conference abstract and a book were collected describing ZS cases associated with twenty animal hosts in five continents. Dogs were by far the most common source among pet owners, while diverse livestock and wildlife contributed to the caseload as an occupational disease. Genetic epidemiological studies of ZS outbreaks are still limited in number, but tools are available to fill this knowledge gap in the near future. Further research is also needed to understand the apparent heterogeneity in the morbidity, disease severity and timing of the response to treatment among people infected with different animal-derived strains.

Canine and Feline Parasitology: Analogies, Differences, and Relevance for Human Health

Cats and dogs are treated as family members by most pet owners. Therefore, a high quality of veterinary care and preventive medicine is imperative for animal health and welfare and for the protection of humans from zoonotic pathogens. There is a general perception of cats being treated as "small dogs," especially in the field of clinical parasitology. As a result, several important differences between the two animal species are not taken into proper consideration and are often overlooked. Dogs and cats are profoundly different under evolutionary, biological, ethological, behavioral, and immunological standpoints. These differences impact clinical features, diagnosis, and control of canine and feline parasites and transmission risk for humans. This review outlines the most common parasitoses and vector-borne diseases of dogs and cats, with a focus on major convergences and divergences, and discusses parasites that have (i) evolved based on different preys for dogs and cats, (ii) adapted due to different immunological or behavioral animal profiles, and (iii) developed more similarities than differences in canine and feline infections and associated diseases. Differences, similarities, and peculiarities of canine and feline parasitology are herein reviewed in three macrosections: (i) carnivorism, vegetarianism, anatomy, genetics, and parasites, (ii) evolutionary adaptation of nematodes, including veterinary reconsideration and zoonotic importance, and (iii) behavior and immune system driving ectoparasites and transmitted diseases. Emphasis is given to provide further steps toward a more accurate evaluation of canine and feline parasitology in a changing world in terms of public health relevance and One Health approach.

Sarcoptic mange: An emerging panzootic in wildlife

Sarcoptic mange, a skin infestation caused by the mite Sarcoptes scabiei, is an emerging disease for some species of wildlife, potentially jeopardizing their welfare and conservation. Sarcoptes scabiei has a near-global distribution facilitated by its forms of transmission and use of a large diversity of host species (many of those with broad geographic distribution). In this review, we synthesize the current knowledge concerning the geographic and host taxonomic distribution of mange in wildlife, the epidemiological connections between species, and the potential threat of sarcoptic mange for wildlife conservation. Recent sarcoptic mange outbreaks in wildlife appear to demonstrate ongoing geographic spread, increase in the number of hosts and increased virulence. Sarcoptic mange has been reported in at least 12 orders, 39 families and 148 species of domestic and wild mammals, making it one of the most generalist ectoparasites of mammals. Taxonomically, the orders with most species found infested so far include Perissodactyla (67% species from the entire order), Artiodactyla (47%), and Diprotodontia (67% from this order). This suggests that new species from these mammal orders are likely to suffer cross-species transmission and be reported positive to sarcoptic mange as surveillance improves. We propose a new agenda for the study of sarcoptic mange in wildlife, including the study of the global phylogeography of S. scabiei, linkages between ecological host traits and sarcoptic mange susceptibility, immunology of individuals and species, development of control strategies in wildlife outbreaks and the effects of global environmental change in the sarcoptic mange system. The ongoing transmission globally and sustained spread among areas and wildlife species make sarcoptic mange an emerging panzootic in wildlife. A better understanding of sarcoptic mange could illuminate the aspects of ecological and evolutionary drivers in cross-species transmission for many emerging diseases.

Current review of isoxazoline ectoparasiticides used in veterinary medicine

The isoxazolines are a novel class of ectoparasiticides with potent inhibitory activity on glutamate- and gamma-aminobutyric acid-gated chloride channel located in nervous system of invertebrates. In recent years, studies have been performed to evaluate the efficacy and safety of isoxazolines against various types of ectoparasites, including fleas, ticks, and mites. As more single and combined isoxazoline products have been approved by the United States Food and Drug Administration and European Medicines Agency, a more comprehensive understanding of isoxazolines becomes essential for veterinary clinical practitioners. This article provides a complete review of isoxazolines with respect to pharmacodynamics, pharmacokinetics, ectoparasiticidal efficacy, and safety, which will provide veterinarians information to allow them to make the best choice of ectoparasiticide for their clients' specific needs.

A review of sarcoptic mange in North American wildlife

The "itch mite" or "mange mite", Sarcoptes scabiei, causes scabies in humans and sarcoptic mange in domestic and free-ranging animals. This mite has a wide host range due to its ability to adapt to new hosts and has been spread across the globe presumably through human expansion. While disease caused by S. scabiei has been very well-studied in humans and domestic animals, there are still numerous gaps in our understanding of this pathogen in free-ranging wildlife. The literature on sarcoptic mange in North American wildlife is particularly limited, which may be due to the relatively limited number of clinically-affected species and lack of severe population impacts seen in other continents. This review article provides a summary of the current knowledge of mange in wildlife, with a focus on the most common clinically-affected species in North America including red foxes (Vulpes vulpes), gray wolves (Canis lupus), coyotes (Canis latrans), and American black bears (Ursus americanus).

Norwegian or Crusted Sarcoptic Mange in Two Leishmanial Dogs

Norwegian or crusted scabies (N/CS) is a rare skin disease with very few cases reported in the dog or the cat. Two adult, stray dogs were admitted in our clinic with a generalized, multifocal to diffuse and nonpruritic dermatitis that was characterized by severe crusting, scaling, and ulceration. In both instances, leishmaniosis and N/CS were diagnosed by immunofluorescent antibody test serology, lymph node cytology, and skin scrapings in which high numbers of Sarcoptes mites were found. The combination of miticidal and antileishmanial treatment, supported by topical treatment and nutritional support, resulted in the complete resolution of the skin lesions and spectacular improvement of the body condition in both cases. Dog 1 eventually died from end-stage kidney disease attributed to leishmaniosis-associated glomerulonephritis, whereas the also proteinuric dog 2 remains clinically healthy. The manifestation of the rare type of N/CS in these dogs could be attributed to cell-mediated immunosuppression, which was most likely induced by leishmaniosis and malnutrition. The necessity of searching for leishmaniosis in those scabietic cases, especially in the endemic areas of leishmaniosis, is strongly recommended.

Efficacy of fluralaner administered either orally or topically for the treatment of naturally acquired Sarcoptes scabiei var. canis infestation in dogs

Background

The efficacy of fluralaner, formulated as a chewable tablet (Bravecto™) or topical solution (Bravecto™ Spot-on Solution), was evaluated against naturally acquired Sarcoptes scabiei var. canis infestation in dogs.

Methods

The study was performed in privately-owned dogs naturally infested with S. scabiei var. canis. All dogs living in the same household as the infested dog were enrolled into one of 3 groups (2 fluralaner treated and 1 negative control). All dogs within one household were administered the same treatment, with one dog per household included in further observations and assessments. In total, 29 dogs confirmed positive for sarcoptic mange were included. On Day 0, all dogs in group 1 (n = 9) were treated once orally with fluralaner at a minimum dose of 25 mg/kg body weight; all dogs in group 2 (n = 11) were treated once topically with fluralaner at a dose of 25 mg/kg body weight; and dogs in group 3 (n = 9) were treated once topically with saline solution. Sarcoptes scabiei var. canis mites on each dog were counted before treatment and at 4 weeks after treatment in deep skin scrapings (~4 cm²) from 5 different body areas. Clinical signs of infestation (i.e. erythematous papules; casts, scales and crusts; body areas with hair loss) and pruritus were recorded at the same time points.

Results

Single oral or topical treatment with fluralaner resulted in a 100 % reduction in mite counts post-treatment (group 1: P = 0.0009 and group 2: P = 0.0011). Resolution of clinical signs at four weeks post-treatment was variable, with improvement observed for erythematous papules, casts and crusts, and pruritus. All fluralaner treated dogs showed an improvement in overall hair re-growth compared with pre-treatment observations.

Conclusion

Fluralaner administered either orally or topically to naturally infested dogs eliminates Sarcoptes scabiei var. canis mites and improves clinical signs over a 4-week observation period.

Evaluation of an ELISA using recombinant Ssλ20ΔB3 antigen for the serological diagnosis of Sarcoptes scabiei infestation in domestic and wild rabbits

An ELISA, based on the Sarcoptes scabiei Ssλ20ΔB3 inmunodominant antigen, was evaluated for the detection of antibodies to S. scabiei in experimentally infested (n=10), farm (n=109), and wild (n=78) rabbit sera. The S. scabiei antigen Ssλ20ΔB3, a major structural protein present over the entire mite's body, was produced as a recombinant protein in Escherichia coli and purified for its use in the ELISA. The resulting ELISA showed, in experimentally infested domestic rabbits, detectable specific antibody responses (IgG) above the cut off level from week three post-infestation indicating that the assay is able to detect positive rabbits very early during the course of the infestation. The ELISA was validated on a panel of 109 domestic breeding rabbit sera collected from 26 Spanish farms, of which 41 were obtained from rabbits with skin lesions compatible with sarcoptic mange, 26 with skin lesions compatible with psoroptic mange, and 42 from unexposed individuals from mange-free farms. The ELISA in this group was characterized by 95% sensitivity, 97% specificity, and a high degree of repeatability. In the psoroptic mange compatible lesions group, included in the study as control group for cross-reactivity with the closely related mite Psoroptes cuniculi, cross-reacting antibodies to Ssλ20ΔB3 S. scabiei antigen were detected in 42.30% of the rabbit sera. However, mean% OD values of the sarcoptic-mange group (55.61 ± 39.20%) were significantly higher (p<0.001) than OD values of the psoroptic-mange (3.64% ± 5.4%) and also of the free-mange (0.21% ± 0.67%) groups. In addition, the ELISA was also evaluated in serum samples obtained from both naturally infested and non-infested wild rabbits from Mallorca Island. The sensitivity of the assay for this group was 100% (4 out of the 4 rabbits with sarcoptic mange compatible lesions and presence of S. scabiei mites were seropositive) and the specificity was 90% (67 out of 74 wild rabbits without detectable mange lesions were seronegative). Although, the total number of tested samples from experimentally infested, farm and wild rabbits was limited, our study showed that the ELISA is able to differentiate between infested and non-infested animals in all tested groups with very high sensitivity and specificity indicating that recombinant Ssλ20ΔB3 is a reliable diagnostic antigen. This assay might be a cost-effective tool for detecting the presence of mangy animals and therefore helping prevent spread of mange among domestic rabbits, reducing potential transmission from female breeding rabbits to other farms, and detecting infestation with sarcoptic mange in the wild.

Prevalence of Sarcoptes scabiei infection in pet dogs in southern China

Little is known about the prevalence of Sarcoptes scabiei infection in pet dogs in China. In the present study, the prevalence of S. scabiei infection in pet dogs in Guangzhou, southern China, was investigated between January and December, 2009. A total of 3,977 pet dogs admitted to animal hospitals were examined for the presence of S. scabiei using a parasitological approach. The average prevalence of S. scabiei infection in pet dogs is 1.18% (95% confidence interval (CI): 0.85–1.52%). The prevalence of S. scabiei was higher in winter (1.42%; 95% CI: 0.29–2.55%), summer (1.39%; 95% CI: 0.83–1.96%), and autumn (1.1%; 95% CI: 0.53–1.68%) than in spring (0.63%; 95% CI: 0.02–1.25%). Furthermore, the prevalence of S. scabiei was the highest in Pekingese (21.88%; 95% CI: 7.55–36.2%), followed by Papillon (5.26%; 95% CI: 0–11.06%) and Bichon Frise (3.19%; 95% CI: 0–6.75%). The results of the present investigation indicate that S. scabiei infection is prevalent in pet dogs in Guangzhou, China, which provides relevant “baseline” data for conducting control strategies and measures against scabies in this region and elsewhere in China. To our knowledge, this is the first comprehensive report of S. scabiei prevalence in pet dogs in China.

Feline sarcoptic mange in Taiwan: a case series of five cats

BACKGROUND

Sarcoptes scabiei infestation is rare in cats.

OBJECTIVE

To report the clinical presentations and treatments of cats infested with S. scabiei.

ANIMALS

Five cats that presented with progressive and nonresponsive crusting lesions on the concave and convex aspects of the pinnae are included in this series. Other dermatological manifestations recorded were crusts on the bridge of the nose (five of five), crusty pododermatitis (three of five), crusty lesions on the tail (one of five) and pruritic erythematous papules on the arms and/or thighs of the owners (five of five). None of the cats was living in a household with a dog.

METHODS

Sarcoptic (S. scabiei) mange was diagnosed based on the identification of S. scabiei in deep skin scrapings. A spot-on application of 1.0% moxidectin and 10% imidacloprid (0.1 mL/kg) was administered every 2 weeks for three applications. All cats were re-evaluated at the time of treatment.

RESULTS

All five cats and their owners improved after the first application and reached clinical remission after the third application. Deep skin scrapings from all cats were negative for S. scabiei after the first application. No clinical adverse effects or abnormalities on routine blood tests were noted during the study period. No reinfestation was reported during the follow-up period of 6 months after treatment.

CONCLUSION

Although sarcoptic mange is rare in cats, it should be considered as a differential diagnosis for cats presenting with crusting lesions on the pinnae and nose and crusty pododermatitis. A spot-on preparation of moxidectin and imidacloprid was used successfully to treat cats with S. scabiei infestation.