Animals as a reservoir of human ringworm in New Zealand

German-Wide Analysis of the Prevalence and the Propagation Factors of the Zoonotic Dermatophyte Trichophyton benhamiae

For about 10 years, a new variant of the pathogen Trichophyton (T.) benhamiae has appeared in Germany, characterized by a previously unobserved culture phenotype with a strong yellow reverse. A few studies suggest that this new variety is now the most common zoophilic dermatophyte in Germany. The guinea pig is the main carrier. Exact prevalence measurements are not yet available. Thus, the aim of our ongoing study was to collect data on the frequency and geographic distribution of the pathogen and its phenotypes (white and yellow) in humans and guinea pigs throughout Germany. Our former studies have already shown that animals from large breeding farms are particularly heavily affected. In contrast to this, 21 small, private breedings were sampled and husbandry conditions recorded. This placed us in a position to identify propagation factors and to give recommendations for containment. For animals from private breedings, we detected T. benhamiae with a prevalence of 55.4%, which is a reduction of nearly 40% compared with animals from large breeding farms. As risk factors, we identified the type of husbandry and the contact to other breedings. Furthermore, certain animal races, like Rex guinea pigs and races with long hair in combination with curls were predestined for colonization with T. benhamiae due to their phenotypic coat characteristics. A prevalence for infections with T. benhamiae of 36.2% has been determined for symptomatic pet guinea pigs suspected of having dermatophytosis and is comparable to the study of Kraemer et al. showing a prevalence of 34.9% in 2009 in Germany. The prevalence in humans is stable with about 2-3% comparing the data of 2010-2013 and 2018 in Thuringia. The new type of T. benhamiae was by far the most frequent cause in all settings.

Clinical signs, therapy and zoonotic risk of pet guinea pigs with dermatophytosis

Systematic studies about pet guinea pigs with dermatophytosis are rare. The aim of this study was to evaluate clinical signs, therapy and zoonotic risk of pet guinea pigs with dermatophytosis. Questionnaires from both owners (n = 74) of pet guinea pigs with dermatophytosis and their veterinarians (n = 101) were analysed regarding clinical signs, therapy and data pertinent to zoonotic potential. Trichophyton (T.) mentagrophytes was found in 97% of cases. In the weeks preceding the onset of the clinical signs, a new guinea pig joined the household in 43% of cases. One third of the affected guinea pigs had lived in the household for less than 3 months. Predominant clinical signs were alopecia (83%), scaling (73%) and crusting (70%). The most commonly affected body site was the head (75%). In approximately one quarter of the cases humans showed clinical signs of dermatophytosis, in half the households, only children were affected. Skin lesions were seen most often on the face, the neck and the arms. Pet guinea pigs carrying dermatophytes must be considered a serious zoonotic risk for their owners, especially for children. A major risk factor for dermatophytosis seems to be a recent acquisition of a new guinea pig.

Dermatophytes in pet Guinea pigs and rabbits

PROBLEM ADDRESSED

The frequency of dermatophytes in pet Guinea pigs and rabbits.

OBJECTIVES

To determine the frequency and types of dermatophytes in pet Guinea pigs and rabbits.

METHODS AND APPROACH

First, 2153 samples collected from pet Guinea pigs (n=1132) and rabbits (n=1021) with suspected dermatophytosis and submitted to three different laboratories for fungal culture were analysed. Subsequently, healthy Guinea pigs and rabbits, animals with skin lesions and with noncutaneous diseases were examined prospectively for dermatophytes.

RESULTS

Trichophyton (T.) mentagrophytes was the most common fungal species isolated (91.6% and 72.3% of positive cultures from Guinea pigs (n=431) and rabbits (n=83), respectively). Animals with positive fungal culture did not show any gender predisposition, but affected animals were younger than those with negative fungal culture (P<0.0001) or than healthy animals of the prospective part of the study. Dermatophytes were isolated from 14/164 healthy Guinea pigs and 0/140 healthy rabbits. In addition, fungal cultures of Guinea pigs with skin lesions (n=26) and other diseases (n=25) were positive in 7.7% and 8.0% respectively. Samples collected from 17 rabbits with skin lesions and 32 rabbits with noncutaneous disease were all negative in culture.

CONCLUSIONS

T. mentagrophytes is the most common dermatophyte in pet Guinea pigs and rabbits, asymptomatic carriers are regularly seen in Guinea pigs, but not in rabbits.

Keratinophilic fungi on feathers of pigeon in Maharashtra, India. Keratinophile Pilze auf Taubenfedern in Maharashtra, Indien

Results of a preliminary survey of keratinophilic fungi associated with feathers of pigeon on high rise buildings in Thane district of Maharashtra (India) are reported. A total of 100 samples were examined, of which 67 samples were positive for keratinophilic fungi. Altogether 67 fungal strains belonging to 10 species of seven genera were isolated viz. Chrysosporium indicum (24%), Chrysosporium sp. (2%), Chr. tropicum (8%), Chrysosporium state of Arthroderma tuberculatum (3%), Chrysosporium state of Ctenomyces serratus (15%), Malbranchea pulchella (3%), Malbranchea sp. (1%), Microsporum gypseum (5%), Myriodontium keratinophilum (2%) and Trichophyton terrestre (4%).

Dermatophyte agents in the city of São Paulo, from 1992 to 2002

Dermatophytosis are superficial mycoses caused by fungi that can invade stratum corneum and keratinized tissues. In order to study the frequency of dermatophytes species and the clinical manifestations caused by these fungi, in São Paulo, SP, Brazil, the authors analyzed cultures isolated at the Mycology Laboratory from a selected population (15,300 out-patients of the Hospital das Clínicas, Department of Dermatology, Faculty of Medicine of University of São Paulo) from January 1992 to June 2002. The most prevalent dermatophyte was Trichophyton rubrum (48.7%), followed by Microsporum canis (20.9%), Trichophyton tonsurans (13.8%), Trichophyton mentagrophytes (9.7%), Epidermophyton floccosum (4.1%), and Microsporum gypseum (2.5%). These agents determined more than one clinical manifestation, i.e., tinea corporis (31.5%), tinea capitis (27.5%), tinea unguium (14.8%), tinea cruris (13.9%), tinea pedis (9.9%), and tinea manuum (1.9%). Clinical variants of dermatophytosis and their relationship to the etiologic agents were studied and the results were compared to those obtained in previous studies in other regions of Brazil and in other countries.

Isolation of fungi from the pelage of cats and dogs using the hairbrush technique

A total of 178 cats and 59 dogs in Palmerston North, New Zealand were sampled for the presence of keratinophilic fungi on their pelage; 57.8% had fungi. The fungi were classified in 20 genera with the predominant species being members of the genera; Chrysosporium, Microsporum and Trichophyton. Cats were the major carriers of keratinolytic fungi. 18.5% of the cats and 5.1% of the dogs were either carriers or infected with M. canis. Microsporum canis was a frequent isolate and its distribution had a seasonal variation, with a peak appearing in May-June.

Microsporum canis with polymorphous macroconidia

An atypical strain of Microsporum canis was isolated in our laboratory, which was characterized by a variety of polymorphous macroconidia. These are demonstrated by illustrations. Based on our observation and literature, the relationship between Microsporum canis and Microsporum distortum is discussed. Epidemiologic aspects are mentioned.

Keratinophilic fungi on the hair of goats from the West Bank of Jordan

The mycoflora of the hair in 178 goats from the West Bank of Jordan was analysed and the frequency of occurrence and the relative importance value for the different keratinophilic fungi found were calculated. One hundred and seven species which belong to 38 genera were isolated. Thirty six of these species were either well recognised agents of mycoses (Trichophyton mentagrophytes, T. verrucosum, and M. nanum), or have been frequently isolated from human and animal lesions (Arthroderma spp., Acremonium kiliense, Alternaria alternata, Aspergillus flavus, Cladosporium carionii, and several other species). These potentially pathogenic fungal species comprised 66.9% of all keratinophilic fungi found on the hair of goats. The role of this animal as a reservoir for dermatophytes and other potentially pathogenic fungi is discussed.

Microsporum nanum infection in hog farmers

Microsporum nanum is a dermatophyte that can cause disease in both man and animals and is most frequently associated with ringworm infection in pigs. Human infections are rare in the literature. Three new cases of human M. nanum infection are reported here. Two patients had inflammatory tinea faciei and one had tinea cruris. The patients were successfully treated with clotrimazole or miconazole cream, sometimes combined with griseofulvin. All three patients were hog farmers and lived in the same small rural area. Occupational exposure is suggested as the cause of infection.

Fungi on the hair of large mammals in Egypt

The frequency of occurrence of fungi in 260 hair samples of dog, donkey and cow collected from Veterinary Medicine Hospital of Assiut University was determined. Twenty-three species which belong to fifteen genera were collected. In low frequency, several dermatophytes (Chrysosporium, Microsporum, Arthroderma and Trichophyton) were found as well as some other fungal species pathogenic to man and animals (Aspergillus fumigatus, Stachybotrys chartarum, Scopulariopsis brevicaulis and Cephalosporium acremonium).

[Microsporum nanum. Report of the 2d case of human infection in Brazil]

É comunicado o segundo caso de infecção humana por Microsporum nanum no Brasil. A investigação epidemiológica visando determinar a fonte de infecção não obteve sucesso. O padrão dermatológico das lesões foi o de Tinea corporis clássica.

Vaccination procedures and the infectivity of dermatophyte lesions

By means of an experimental guinea pig model, the immunogenicities of a live spore vaccine, a killed hyphal cell wall vaccine and a soluble cytoplasmic extract vaccine of Trichophyton mentagrophytes var. erinacei were compared, and their modifying influence on the infectivity and duration of experimental dermatophyte lesions examined. Of the three vaccines, the live-spore one was the most effective and closely simulated the type of immunity which develops following a natural infection. Lesions produced in cell wall vaccinated animals revealed significantly less infectivity and were reduced in duration as compared with lesions in unvaccinated animals. The cytoplasmic extract vaccine had no beneficial effect on the course of experimental infection; indeed it seemed to increase the infectivity of lesions. Acquired resistance to reinfection in a pregnant guinea pig was not passed on to the offspring. Significant levels (titer of greater than or equal to 1:16) of antibody were detected in the sera of all infected and vaccinated animals using an indirect fluorescent antibody technique and germling antigens. Using counterimmunoelectrophoresis, precipitating antibodies were detectable in the sera of all seven animals vaccinated with the cell wall or cytoplasmic extract, in one (20%) of the control animals after reinfection, and none of the four animals injected subcutaneously with the live spore vaccine. Thus no correlation between antibody titer and the severity and duration of lesions was observed. These results endorse the growing hypothesis that cell mediated immunity is of prime importance in protection again dermatophyte invasion and suggests that prophylactic vaccination procedures are worthy of further evaluation in lower animals.

Dermatophyte prevalence in Wellington, New Zealand

Over a 5 year period (1975-1979) 746 dermatophytes were isolated from 4,234 patients examined in the Wellington area of New Zealand. Trichophyton rubrum was the predominant isolate, although the Microsporum canis isolation rate was also high, especially in children.

Zoophilic dermatophytes and their natural hosts in Western Australia

Zoophilic dermatophytes were a common source of both human and animal ringworm infections in Western Australia. Microsporum canis was the chief aetiologic agent of infections in kittens and children. Trichophyton mentagrophytes was isolated from domestic pets, farm animals, laboratory animals and wild animals as well as humans. T. verrucosum was a less frequent cause of infection in both man and animals. Other zoophilic species isolated included M. Gypseum, M. nanum and T. equinum var. autotrophicum.

First European report of swine infection by Microsporum nanum

The first European case of swine infection by Microsporum nanum is reported. The infected pig came from a farm in the Emilia-Romagna region of Italy. European records of human and lower animal infections by this fungus and soil isolation records are discussed.