Evaluation of cats as the source of endemic sporotrichosis in Peru

S. Freitas D, M. de Macedo P, A. Pereira S, D. F. Gremião I, Coelho FC. Mathematical model of the dynamics of transmission and control of sporotrichosis in domestic cats

Sporotrichosis is a subcutaneous mycosis with a global distribution, also known as "rose gardener's disease". Brazil is experiencing a rapid spread of the zoonotic transmission of of Sporothrix brasiliensis, the main etiological agent of this disease in this country, affecting domestic felines. Cost-effective interventions need to be developed to control this emergent public health problem. To allow for the comparison of alternative control strategies, we propose in this paper, a mathematical model representing the transmission of S. brasiliensis among cats, stratified by age and sex. Analytical properties of the model are derived and simulations show possible strategies for reducing the endemic levels of the disease in the cat population, with a positive impact on human health. The scenarios included mass treatment of infected cats and mass implementation of contact reduction practices, such as neutering. The results indicate that mass treatment can reduce substantially the disease prevalence, and this effect is potentialized when combined with neutering or other contact-reduction interventions. On the other hand, contact-reduction methods alone are not sufficient to reduce prevalence.

Anti-Sporothrix Antibody Detection in Domestic Cats as an Indicator of a Possible New Occurrence Area for Sporotrichosis in North Brazil

Feline sporotrichosis has emerged as an important public health issue in some countries, especially Brazil. Currently, zoonotic transmission of Sporothrix brasiliensis by domestic cats is the major sporotrichosis spread form throughout this country. Sporotrichosis in Brazil is a good model for the One Health concept application, which connects the environment, human and animal health. Under this thinking, the aim of this study was to investigate the seroprevalence of sporotrichosis in cats from Rolim de Moura, Rondônia, Brazil, using antibody detection by an ELISA test previously validated for human diagnosis. For the standardization of this test, 30 serum samples from cats with proven sporotrichosis and 11 sera from healthy cats were used. The assay showed 87% sensitivity and 100% specificity for the diagnosis of feline sporotrichosis. After the standardization, 202 serum samples from distinct cats from Rolim de Moura were evaluated. The test was positive in 63 (31.19%) cats from the studied area. A multivariate analysis revealed that living far from forest or agricultural areas as well as pure breed animals had higher odds ratios (3.157 and 2.281, respectively) for the presence of detectable levels of anti-Sporothrix antibodies. These results show the applicability of this assay in the detection of anti-Sporothrix antibodies in feline serum samples and point to a putative new occurrence area of urban sporotrichosis dispersing to the North region of Brazil.

The threat of emerging and re-emerging pathogenic Sporothrix species

Sporotrichosis is a neglected subcutaneous mycosis of humans and animals acquired by traumatic inoculation of soil and plant material (classical route) contaminated with infectious propagules of the pathogen or being bitten/scratched by infected cats (alternative route). Within a genus composed of 53 species displaying an essentially environmental core, there are only a few members which have considerable impacts on human or animal health. Infections are typically caused by S. brasiliensis, S. schenckii or S. globosa. Rare mammal pathogens include members of the S. pallida and S. stenocereus complexes. To illustrate the tremendous impact of emerging zoonotic sporotrichosis on public health, we discuss the main features of the expanding epidemics driven by S. brasiliensis in cats and humans. The cat entry in the transmission chain of sporotrichosis, causing epizooties (cat-cat) or zoonosis (cat-human), has contributed to the definition of new paradigms in Sporothrix transmission, reaching epidemic levels, making the disease a serious public health problem. Indeed, S. brasiliensis infection in humans and animals is likely to become even more important in the future, with projections of its expansion in biogeographic domains and host range, as well as greater virulence in mammals. Therefore, lessons from a long-standing outbreak in the state of Rio de Janeiro about the source and distribution of the etiological agents among outbreak areas can be used to create better control and prevention plans and increase awareness of sporotrichosis as a serious emerging zoonotic disease.

The interaction between Sporothrix schenckii sensu stricto and Sporothrix brasiliensis with Acanthamoeba castellanii

BACKGROUND

Sporotrichosis is a group of zoonotic subcutaneous mycoses, found worldwide and caused by fungi belonging to the genus Sporothrix. Protozoans of the genus Acanthamoeba are widely distributed, and some species may be pathogenic and/or opportunistic. These organisms coexist in the same environment and may interact.

OBJECTIVES

This study determined the profile of interactions of S schenckii sensu stricto and S brasiliensis with A castellanii, using an in vitro co-culture model to evaluate the intrinsic characteristics of the two Sporothrix species and A castellanii.

METHODS

We compared the rate of phagocytosis of S schenckii sensu stricto and S brasiliensis by A castellanii; the viability of S schenckii sensu stricto and S brasiliensis after contact with A castellanii; the viability of the amoeba after contact with a fungal species; and the influence of S schenckii sensu stricto and S brasiliensis on the encystment process of A castellanii.

RESULTS

The analyses indicated that A castellanii phagocytised both S schenckii and S brasiliensis, with significantly more S schenckii than S brasiliensis in the first two hours of contact. Our results showed a significant increase in conidia and hyphae count after 72 hours of co-culture of A castellanii with S brasiliensis, and the amoebae lysed after they ingested the fungi, indicating that the fungi probably used the amoebae as a source of nutrition.

CONCLUSIONS

Our results were obtained in vitro and these organisms may not behave similarly in vivo; in vivo studies of co-infections are necessary in order to gain a thorough understanding of this relationship.

Sporotrichosis in the Ocular Adnexa: 21 Cases in an Endemic Area in Peru and Review of the Literature

PURPOSE

To describe the clinical and epidemiologic characteristics of sporotrichosis in ocular adnexa and give an insight into factors associated with this condition.

DESIGN

Retrospective case series and literature review.

METHODS

We retrospectively reviewed all cases of sporotrichosis in ocular adnexa between 2004 and 2014 in the Santa Teresa Clinic of Abancay, Peru and reviewed all case reports of sporotrichosis in ocular adnexa in the literature.

RESULTS

We reviewed records of 21 patients with sporotrichosis in ocular adnexa; 12 (57.1%) of them were male and their median age surrounded 9 years. In our series, 19 patients had lesions in the eyelids and 2 in the eyebrows. The lymphocutaneous form occurred in 62% of them. Ten patients (47.6%) were cured with potassium iodide. Among 65 patients with sporotrichosis in ocular adnexa (our 21 patients and 44 from the literature), the average age was 9 years, and 78% were ≤15 years of age; 54% were male. The lesions were more frequent on the eyelids (n = 53 [82%]), followed by the lacrimal gland (n = 5), conjunctiva (n = 4), and eyebrows (n = 3). The lymphocutaneous clinical form (54%) was the most frequent. Fifty patients were cured: 31 of them with potassium iodide, 16 with itraconazole, and 3 with a combination including potassium iodide, itraconazole, and fluconazole. Twenty-nine patients (44.6%) resided in a hyperendemic region, and 5 patients reported contact with cats that had sporotrichosis.

CONCLUSIONS

Sporotrichosis in ocular adnexa is associated with children ≤15 years of age, and in 82% of these cases the disease is limited to the eyelids.

In vitro susceptibility of antifungal drugs against Sporothrix brasiliensis recovered from cats with sporotrichosis in Brazil

Sporotrichosis is an important subcutaneous mycosis of humans and animals. Classically, the disease is acquired upon traumatic inoculation of Sporothrix propagules from contaminated soil and plant debris. In addition, the direct horizontal transmission of Sporothrix among animals and the resulting zoonotic infection in humans highlight an alternative and efficient rout of transmission through biting and scratching. Sporothrix brasiliensis is the most virulent species of the Sporothrix schenckii complex and is responsible for the long-lasting outbreak of feline sporotrichosis in Brazil. However, antifungal susceptibility data of animal-borne isolates is scarce. Therefore, this study evaluated the in vitro activity of amphotericin B, caspofungin, itraconazole, voriconazole, fluconazole, and ketoconazole against animal-borne isolates of S. brasiliensis. The susceptibility tests were performed through broth microdilution (M38-A2). The results show the relevant activity of itraconazole, amphotericin B, and ketoconazole against S. brasiliensis, with the following MIC ranges: 0.125-2, 0.125-4 and 0.0312-2 μg/ml, respectively. Caspofungin was moderately effective, displaying higher variation in MIC values (0.25-64 μg/ml). Voriconazole (2-64 μg/ml) and fluconazole (62.5-500 μg/ml) showed low activity against S. brasiliensis strains. This study contributed to the characterization of the in vitro antifungal susceptibility of strains of S. brasiliensis recovered from cats with sporotrichosis, which have recently been considered the main source of human infections.

Sporotrichosis: The Story of an Endemic Region in Peru over 28 Years (1985 to 2012)

BACKGROUND

Abancay province is a long-standing geographical focus of sporotrichosis in the south central highlands of Peru. Therefore, we examined the features of 36 newly identified cases of sporotrichosis from two hospital centers in Abancay province. We also performed a literature review of studies conducted in this endemic geographical focus over a period of 28 years (1998 to 2012), and analyzed the demographic, clinical and epidemiological features of sporotrichosis in the cases reported in these studies.

METHODOLOGY

We examined the features of 36 new cases of sporotrichosis identified from two hospital centers in Abancay. Furthermore, we searched for relevant studies of cases of sporotrichosis in the endemic region using healthcare databases and literature sources. We analyzed a detailed subset of data on cases collected in Abancay, neighboring provinces, and other regions of Peru.

RESULTS

A total of nine studies were identified, with 1467 cases included in the final analysis. We also analyzed 36 new cases found in the two hospital centers. Therefore, the combined total of cases analyzed was 1503. Of this total, 58% were male, and approximately 62% were aged ≤14 years. As expected, most cases were from Abancay province (88%), although 12% were from neighboring provinces and other regions of Peru. The lymphocutaneous form (939 cases) was the commonest. The face was the most commonly affected region (647 cases). A total of 1224 patients (81.4%) received treatment: 95.8% received potassium iodide, 2.6% ketoconazole and 1.6% itraconazole. The overall success rates were 60.7% with potassium iodide, 32.2% with ketoconazole and 85% with itraconazole.

CONCLUSIONS

The epidemic of sporotrichosis has been occurring for three decades in the province of Abancay in Peru. This mycosis affects primarily the pediatric population, with predominantly the lymphocutaneous form in the facial region. Although treatment with potassium iodide is safe and effective, response and adherence to treatment are influenced by its duration, cost, accessibility, and side effects.

Sporotrichosis in Iran: A mini review of reported cases in patients suspected to cutaneous leishmaniasis

Sporotrichosis is a chronic subcutaneous fungal infection with global distribution. It is a rare fungal infection with nine reported cases in Iran, including eight humans and one animal, within the past 30 years. Among the human cases, seven were of the fixed cutaneous type of sporotrichosis and one had sporotrichoid lymphocutaneous. The reported patients were within the age range of 23-60 years, and six of them were female. The most frequent sites of infection were forearms and hands, as well as the face and legs. In addition, the majority of the cases had previously been suspected of leishmaniasis and received treatment. Sporotrichosis is not a well-known condition in Iran and is often misdiagnosed and erroneously treated for other cutaneous parasitic or bacterial infections with similar clinical manifestations. Therefore, sporotrichosis should be taken into account in the differential diagnosis of nodular-ulcerative skin lesions.

Emerging sporotrichosis is driven by clonal and recombinant Sporothrix species

Sporotrichosis, caused by agents of the fungal genus Sporothrix, occurs worldwide, but the infectious species are not evenly distributed. Sporothrix propagules usually gain entry into the warm-blooded host through minor trauma to the skin from contaminated plant debris or through scratches or bites from felines carrying the disease, generally in the form of outbreaks. Over the last decade, sporotrichosis has changed from a relatively obscure endemic infection to an epidemic zoonotic health problem. We evaluated the impact of the feline host on the epidemiology, spatial distribution, prevalence and genetic diversity of human sporotrichosis. Nuclear and mitochondrial markers revealed large structural genetic differences between S. brasiliensis and S. schenckii populations, suggesting that the interplay of host, pathogen and environment has a structuring effect on the diversity, frequency and distribution of Sporothrix species. Phylogenetic data support a recent habitat shift within S. brasiliensis from plant to cat that seems to have occurred in southeastern Brazil and is responsible for its emergence. A clonal structure was found in the early expansionary phase of the cat–human epidemic. However, the prevalent recombination structure in the plant-associated pathogen S. schenckii generates a diversity of genotypes that did not show any significant increase in frequency as etiological agents of human infection over time. These results suggest that closely related pathogens can follow different strategies in epidemics. Thus, species-specific types of transmission may require distinct public health strategies for disease control.

Isolation of Sporothrix schenckii from the claws of domestic cats (indoor and outdoor) and in captivity in São Paulo (Brazil)

Sporotrichosis is a subcutaneous mycosis and is also a zoonosis (sapro- and anthropozoonosis). The objective of the present study was to determine the occurrence of sporotrichosis in domestic cats and in wild or exotic felines in captivity through the isolation of Sporothrix spp. from claw impressions in a culture medium. The samples included 132 felines, of which 120 (91.0 %) were domestic cats, 11 (8.3 %) were wild felines, and one (0.7 %) was an exotic felid. Twenty-one (17.5 %) were outdoor cats. Of the total, 89 (67.4 %) had contact with other animals of the same species. It was possible to isolate Sporothrix schenckii from the claws of one (0.7 %) of the felids probed; this animal exhibited generalised sporotrichosis and had infected a female veterinarian. The potential pathogenic agents Microsporum canis and Malassezia pachydermatis were isolated in 12.1 and 5.3 % of the animals, respectively. The following anemophilous fungi, which were considered to be contaminants, were also isolated: Penicillium sp. (28 or 21.2 %), Aspergillus sp. (13 or 9.8 %), Rhodotorula sp. (5 or 3.8 %), Candida sp. (5 or 3.8 %), Trichoderma sp. (1 or 0.7 %), and Acremonium sp. (1 or 0.7 %). Due to the low magnitude of occurrence (0.7 %) of Sporothrix in feline claws, the potential of the cats evaluated in this study to be sources of infection in the city of São Paulo is considerably low.

Cutaneous sporotrichosis: a six-year review of 19 cases in a tertiary referral center in Malaysia

BACKGROUND

Sporotrichosis is a subcutaneous fungal infection caused by a thermally dimorphic aerobic fungus, Sporothrix schenckii. It results from traumatic inoculation or contact with animals. Most cases were reported mainly in the tropics and subtropics.

OBJECTIVE

  The objective of our study is to assess the clinical characteristic of cutaneous sporotrichosis among our patients.

METHODOLOGY

We performed a retrospective review of all cases diagnosed with cutaneous sporotrichosis from July 2004 to June 2010. Patients' medical records were retrieved and analyzed according to demography, preceding trauma, sites of lesions, clinical subtypes, treatment, and clinical response.

RESULTS

Nineteen cases were diagnosed with cutaneous sporotrichosis with a male/female ratio of 9:10. Thirteen cases (68.4%) were able to recall preceding trauma, and seven of them reported cat scratches or cat bites. Lymphocutaneous sporotrichosis was observed in 13 cases (68.4%) followed by four cases of fixed cutaneous sporotrichosis and two cases of disseminated sporotrichosis. Histologically, 11 cases (57.8%) demonstrated a granulomatous reaction. Sporothrix schenckii was cultured in 12 cases (63.2%). Thirteen cases (68.4%) were successfully treated with oral itraconazole alone for a mean duration of 15.6 weeks. Two cases with disseminated cutaneous sporotrichosis were treated with intravenous amphotericin B.

CONCLUSION

  Lymphocutaneous sporotrichosis was the most common subtype of cutaneous sporotrichosis in our series, with cat scratches or bites being the most common preceding trauma. Oral itraconazole was highly effective for the localized subtypes, whereas intravenous amphotericin B was required in disseminated cutaneous sporotrichosis.

Unusual clinical presentation of sporotrichosis in three members of one family

INTRODUCTION

Sporotrichosis is a mycosis caused by the dimorphic fungus Sporothrix spp., and the primary mode of transmission is traumatic inoculation of fungus conidia from plants and other organic matter.

METHODS

Sporotrichosis was established in a cat and in three members of one family from a rural area, by fungal growth in culture.

RESULTS

The cutaneous lesions developed on the lower buttock and limbs with no report of any injury.

CONCLUSION

Although sporotrichosis should be considered for differential diagnosis in people working with soil and plants, cases of chronic lesions on skin of cats and in households is probably a new epidemiological approach in a given geographic region.

Sporothrix schenckii and Sporotrichosis

Sporotrichosis, which is caused by the dimorphic fungus Sporothrix schenckii, is currently distributed throughout the world, especially in tropical and subtropical zones. Infection generally occurs by traumatic inoculation of soil, plants, and organic matter contaminated with the fungus. Certain leisure and occupational activities, such as floriculture, agriculture, mining, and wood exploitation, are traditionally associated with the mycosis. Zoonotic transmission has been described in isolated cases or in small outbreaks. Since the end of the 1990s there has been an epidemic of sporotrichosis associated with transmission by cats in Rio de Janeiro, Brazil. More than 2,000 human cases and 3,000 animal cases have been reported. In humans, the lesions are usually restricted to the skin, subcutaneous cellular tissue, and adjacent lymphatic vessels. In cats, the disease can evolve with severe clinical manifestations and frequent systemic involvement. The gold standard for sporotrichosis diagnosis is culture. However, serological, histopathological, and molecular approaches have been recently adopted as auxiliary tools for the diagnosis of this mycotic infection. The first-choice treatment for both humans and cats is itraconazole.

Molecular characterisation of Sporothrix schenckii isolates from humans and cats involved in the sporotrichosis epidemic in Rio de Janeiro, Brazil

An epidemic of sporotrichosis, a subcutaneous mycosis caused by the fungus Sporothrix schenckii, is ongoing in Rio de Janeiro, Brazil, in which cases of human infection are related to exposure to cats. In an attempt to demonstrate the zoonotic character of this epidemic using molecular methodology, we characterised by DNA-based typing methods 19 human and 25 animal S. schenckii isolates from the epidemic, as well as two control strains. To analyse the isolates, the random amplified polymorphic DNA (RAPD) technique was performed using three different primers, together with DNA fingerprinting using the minisatellite derived from the wild-type phage M13 core-sequence. The analyses generated amplicons with considerable polymorphism. Although isolates exhibited high levels of genetic relatedness, they could be clustered into 5-10 genotypes. The RAPD profiles of epidemic S. schenckii isolates could be distinguished from that of the United States isolate, displaying 20% similarity to each primer and 60% when amplified with the M13 primer. DNA fingerprinting of S. schenckii isolated from the nails (42.8%) and the oral cavities (66%) of cats were identical to related human samples, suggesting that there is a common infection source for animals and humans in this epidemic. It is clear that cats act as a vehicle for dissemination of S. schenckii.

Attempted isolation of Blastomyces dermatitidis from the nares of dogs: Northern Wisconsin, USA

The nasal cavities of domestic animals may concentrate and allow isolation of environmentally acquired fungal pathogens. We obtained two swabs each from the nares of 110 asymptomatic, physically normal dogs from a veterinary practice in Eagle River, WI, USA, an area highly endemic for blastomycosis. Four of the tested dogs had past histories of blastomycosis. Samples were placed on yeast extract phosphate (Smith's) media at 20 degrees C but growth of Blastomyces dermatitidis was not observed on any of the 220 cultures. One dog developed cytologically confirmed B. dermatitidis one month following culture of its samples, 6 died of other illnesses, while 91/103 dogs completing follow-up have remained asymptomatic for three years. We did not observe nasal colonization by B. dermatitidis in this population of dogs with potential for sniffing and digging in an environment highly endemic for this fungus.