Epidemiology of human dermatophytoses in Africa.

In this critical literature review, we summarize the epidemiological trends of dermatophytoses reported in Africa. Our findings clearly emphasize the heavy burden of dermatophytosis in Africa. Tinea capitis is the primary clinical presentation of dermatophytosis in African children throughout the entire African continent. The disease affects more than 20% of school-age children in West Africa, while the prevalence ranges from 10% to more than 70% in other regions of Africa. In African adults, the presence of tinea corporis is the most frequent indicator of dermatophytosis. However, epidemiological studies have been primarily conducted on particular patient groups that are not representative of the general population. We examined dermatophyte species distribution patterns. We observed a predominance of anthropophilic dermatophytes, mainly T. violaceum, in the North and East of Africa and both T. soudanense and M. audouinii in the Western and Central regions of the continent. Interestingly, the zoophilic species, M. canis, has recently emerged in North and East Africa. Optimization of both mycology diagnosis capacities and epidemiological methodology would provide insight into the role that climate and other global aspects of the human environment play in dermatophyte epidemiology. We advocate that using a multisectoral and collaborative strategy would strengthen such future studies.

New insights in dermatophyte research.

Dermatophyte research has renewed interest because of changing human floras with changing socioeconomic conditions, and because of severe chronic infections in patients with congenital immune disorders. Main taxonomic traits at the generic level have changed considerably, and now fine-tuning at the species level with state-of-the-art technology has become urgent. Research on virulence factors focuses on secreted proteases now has support in genome data. It is speculated that most protease families are used for degrading hard keratin during nitrogen recycling in the environment, while others, such as Sub6 may have emerged as a result of ancestral gene duplication, and are likely to have specific roles during infection. Virulence may differ between mating partners of the same species and concepts of zoo- and anthropophily may require revision in some recently redefined species. Many of these questions benefit from international cooperation and exchange of materials. The aim of the ISHAM Working Group Dermatophytes aims to stimulate and coordinate international networking on these fungi.

[Trichophyton mentagrophytes-from snow leopard to man : A molecular approach for uncovering the chain of infection]. / Trichophyton mentagrophytes ­ vom Schneeleoparden zum Menschen : Ein molekularer Ansatz zur Aufdeckung der Infektionskette.

Sources of infection for Trichophyton (T.) mentagrophytes-a zoophilic dermatophyte-comprise pet rodents (guinea pigs, mice, rabbits) and sometimes cats. Human infections due to dermatophytes after contact with zoo animals, however, are extreme rare. Four zoo keepers from Basel Zoo were diagnosed to suffer from tinea manus and tinea corporis due to T. mentagrophytes. The 22-year-old daughter of one zoo keeper was also infected with tinea corporis after having worked in the snow leopard section for one day. The strain of the index patient was confirmed by a direct uniplex-PCR-EIA and sequence analysis of the ribosomal internal transcribed spacer (ITS) region (18S rRNA, ITS1, 5.8S rRNA, ITS2, 28S rRNA) as T. mentagrophytes. Three young snow leopards from Basel Zoo were identified as the origin of the fungal skin infection. The transmission occurred due to direct contact of the zoo keepers with the young snow leopards when removing hedgehog ticks (Ixodes hexagonus). Two adult snow leopards had developed focal alopecia of the facial region which was diagnosed as dermatomycoses due to T. mentagrophytes by the zoo veterinarians. By sequence analysis, both the strains from the animals and a single strain of the index patient showed 100% accordance proving transmission of T. mentagrophytes from animals to the zoo keepers. Molecular biological identification revealed a strong relationship to a strain of T. mentagrophytes from European mink (Mustela lutreola) from Finland. Treatment of patients was started using topical ointment with azole antifungals, and oral terbinafine 250 mg once daily for 4 weeks. Both adult snow leopards and the asymptomatic young animals were treated with oral itraconazole.

Molecular epidemiology of Trichophyton quinckeanum - a zoophilic dermatophyte on the rise.

BACKGROUND: Formerly only referred to as a subspecies (T. mentagrophytes var. quinckeanum), T. quinckeanum once again constitutes a distinct species according to the updated taxonomy of dermatophytes. PATIENTS AND METHODS: During routine diagnostic tests conducted at the Mycology Laboratory, Mölbis, Germany, between 11/2013 to 1/2017 (three years and three months), all specimens sent in were examined for T. quinckeanum. Molecular biology methods employed included: 1) DNA hybridization (PCR ELISA), 2) gene sequencing of the ITS region and TEF-1α, and 3) in some cases, MALDI-TOF mass spectrometry. RESULTS: Overall, 62 strains of T. quinckeanum were found. Sixty-eight percent of patients were female; 43 % were children and adolescents (≤ 19 years of age). Cats were a frequent source of infection. Sequencing of all 62 strains revealed a concordance of 100 % with T. quinckeanum sequences contained in the NCBI database. Isolates analyzed by MALDI-TOF mass spectrometry showed specific spectra. CONCLUSIONS: In Germany, the zoophilic dermatophyte T. quinckeanum currently appears to be more prevalent than expected. T. quinckeanum strains were isolated from children and adults with dermatomycosis and tinea capitis. Sources of infection with T. quinckeanum include small rodents (mice), horses, and - remarkably commonly -  cats. Given that unequivocal morphological identification of this dermatophyte is not always possible, molecular methods have to be employed in the diagnosis.

Detection of dermatophytes in human nail and skin dust produced during podiatric treatments in people without typical clinical signs of mycoses.

Pedicures are the most common cosmetic foot treatment. Many pedicurists and podiatrists suffer from respiratory infections and diseases such as asthma, sinusitis, chronic cough and bronchitis. Skin and nail dust may play an important role in the development of occupational diseases and the transmission of mycosis to other clients. To examine the presence of dermatophytes in nail and skin dust produced during podiatric treatments of people without typical symptoms of mycosis and to assess the epidemiological hazards of tinea pedis for podiatrists as well as other clients. Seventy-seven samples underwent direct microscopy and culture. The results of direct microscopy were positive in 28/77 samples (36.36%) and doubtful in 3/77 (3.9%). Fungi were cultured from 36/77 samples (46.75%), including 8/77 (10.3%) positive for dermatophytes (Trichophyton rubrum-6 isolates and Trichophyton mentagrophytes-2). Material collected during podiatric treatments is potentially infected by pathogenic fungi; thus, there is a need to protect both workers who perform such treatments, as well as other clients, to prevent the transmission of pathogens in the Salon environment. Exposure to this occupational hazard may increase not only the risk of respiratory infections but also increase asthmatic or allergic reactions to Trichophyton.

Infection and transmission heterogeneity of a multi-host pathogen (Batrachochytrium dendrobatidis) within an amphibian community.

The majority of parasites infect multiple hosts. As the outcome of the infection is different in each of them, most studies of wildlife disease focus on the few species that suffer the most severe consequences. However, the role that each host plays in the persistence and transmission of infection can be crucial to understanding the spread of a parasite and the risk it poses to the community. Current theory predicts that certain host species can modulate the infection in other species by amplifying or diluting both infection prevalence and infection intensity, both of which have implications for disease risk within those communities. The fungus Batrachochytrium dendrobatidis (Bd), the causal agent of the disease chytridiomycosis, has caused global amphibian population declines and extinctions. However, not all infected species are affected equally, and thus Bd is a good example of a multi-host pathogen that must ultimately be studied with a community approach. To test whether the common midwife toad Alytes obstetricans is a reservoir and possible amplifier of infection of other species, we used experimental approaches in captive and wild populations to determine the effect of common midwife toad larvae on infection of other amphibian species found in the Peñalara Massif, Spain. We observed that the most widely and heavily infected species, the common midwife toad, may be amplifying the infection loads in other species, all of which have different degrees of susceptibility to Bd infection. Our results have important implications for performing mitigation actions focused on potential 'amplifier' hosts and for better understanding the mechanisms of Bd transmission.

High dermatophyte contamination levels in hairdressing salons of a West African suburban community.

Tinea capitis is a dermatophyte infection of scalp is commonly spread by currently infected patients, asymptomatic carriers or by fomites, such as hairdressing tools. However, studies on the risk factors of Tinea capitis remain scarce. The aim of this study was to evaluate the dermatophytes contamination level of the hairdressing tools to which hairdressing salon customers are exposed in Sirakoro-Méguétana, a suburb of Bamako, the capital city of Mali. A total of 41 hairdressing tools were sampled in five hairdressing salons. Two anthropophilic dermatophytes species, Microsporum audouinii (53.3%) and Trichophyton soudanense (46.7%), were cultured from 30 (73.2%) samples. This first study, addressing hairdressing salons dermatophyte contamination, revealed a strikingly high contamination of hairdressing tools with dermatophyte propagules, which exposes hairdressing salons customers to an important dermatophytosis risk. The sterilisation of hairdressing tools is central to preventing dermatophytoses spreading. Appropriate community information and hairdressers training should be implemented in this view.

Trichophyton verrucosum infection in cattle farms of Umbria (Central Italy) and transmission to humans.

Trichophyton verrucosum is the most common ringworm agent in cattle. Epidemiology of cattle dermatophytoses in Central Italy is not clear. Its diffusion among cattle and herdsmen was investigated in 20 Umbrian farms, Central Italy. Hairs and scales were taken from 395 animals and 31 workers. Typical ringworm was present in 71.7% of cattle under 6 months and in 11% of animals over 6 months. T. verrucosum was isolated from 98.9% of symptomatic heads and was the most prevalent dermatophyte in all herds investigated (isolated in 18 of the 20 farms). T. mentagrophytes var. mentagrophytes was found in 16 symptomatic and in eight asymptomatic young animals. Prevalence of asymptomatic carriers of both species was significantly higher in young heads (21.1% vs. 8.1%) and the age below 6 months was the only statistically significant risk factor associated with dermatophytosis. About the workers, all the 14 men with lesions were positive for T. verrucosum; copresence of T. verrucosum and Microsporum gypseum was noticed in one case. Results indicate a high diffusion of T. verrucosum among both animals and humans in Umbrian farms and confirm the dermatophyte infection as a public health problem. Periodic epidemiological surveys, treatment of sick livestock and workers, cleaning/sanitisation of herds and vaccination programmes may be useful in controlling the infection.

Subcutaneous (deep) fungal infections.

Fungal infection is a common clinical problem in dermatology. While most cases in practice are superficial infections, invasive subcutaneous mycoses are important to recognize and treat, as these conditions often have significant morbidity and mortality. Deep fungi demonstrate species-specific syndromes and may be identified by clinical and histological features in addition to serological evaluation and culture. Identification of the common innoculation subcutaneous mycoses, as well as those associated with pulmonary primary infection and dissemination to the skin is important, as treatments vary by organism and clinical setting. This overview will help to identify the key dermatological presentations of subcutaneous fungal infection, and the clues they give to cause.

Coccidioidomycosis.

Coccidioidomycosis is a common, environmentally acquired, pulmonary fungal infection in arid and semi-arid regions of the West, especially Arizona and California. The infection is frequently associated with striking cutaneous manifestations. Reactive, immunologically mediated eruptions include erythema nodosum, a generalized exanthem, Sweet syndrome, and reactive granulomatous dermatitis. Less commonly, the skin can harbor the actual organisms as a result of dissemination from the lungs. Dermatologists may play a key role in the recognition of coccidioidomycosis

[Dermatophytes transmitted by pets and cattle]. / Dermatophytes transmis par les animaux domestiques.

Most inflammatory skin and hair dermatophytoses are caused by one of four zoophilic dermatophyte species: Microsporum canis (from cats and dogs), Trichophyton verrucosum (from cattle), Arthroderma benhamiae (from Guinea-pigs) and Arthrodermna vanbreuseghemii (generally from cats and dogs). In cases of highly inflammatory tinea corporis, tinea faciae and tinea capitis in humans, it is important to identify with certainty the precise etiologic agent and to examine pets as the possible source of infection. The recurrence of infections or new infections can be prevented by adequately treating incriminated domestic animals and their environments. Cooperation between the medical and veterinary professions is required in this situation.

Molecular analysis of dermatophytes suggests spread of infection among household members.

Dermatophyte infection from the same strains may be an important route for transmission of dermatophytoses within a household. In this study, we used molecular methods to identify dermatophytes in members of dermatophyte-infected households and evaluated variables associated with the spread of infection. Fungal species were identified by polymerase chain reaction (PCR) using primers targeting the internal transcribed spacer (ITS) regions (ITS1 and ITS4). For strain differentiation, fungal DNA was probed with a ribosomal DNA-specific probe (containing ITS1, 5.8S ribosomal DNA, and ITS2) to detect restriction fragment length polymorphisms (RFLPs). Associations between the spread of a dermatophyte infection and fungal/host variables were determined using χ² and logistic regression analyses. Among the 50 households enrolled in this study, 18 included multiple infected members (MIMs). Trichophyton rubrum was the most commonly isolated dermatophyte species, followed by Trichophyton mentagrophyts and Epidermophyton floccosum. Sixteen T rubrum strains (TR-A to TR-P) were identified, with spread of infection detected in 8 MIM households. Factors that were significantly (P<.05) associated with the spread of infection included the presence of strains TR-B or TR-D, a history of concomitant tinea pedis and onychomycosis, and plantar scaling and/or nail discoloration. This study is unique in that it used molecular evidence to demonstrate the association of certain strains with the spread of dermatophyte infection among members of the same household.

Cutaneous congenital candidiasis in a full-term newborn from an asymptomatic mother.

A male infant of 2,900 g was born at term to a 19-year-old primigravida woman who had adequate prenatal care and no major complications detected during the pregnancy. The only reported medical event was an episode of urinary tract infection by E. coli one month before delivering, which resolved without complications using nitrofurantoin. There was no history of maternal herpes simplex infection and her serologic screening was negative for syphilis.

Transmission of the major skin microbiota, Malassezia, from mother to neonate.

BACKGROUND: Skin surface colonization starts after birth. It is thought that early microbial colonization affects the development of skin immune functions. Although Malassezia is the predominant fungus in the skin microbiota in healthy individuals, the microorganism is associated with atopic dermatitis and seborrheic dermatitis. In the present study, transmission of skin microbiota from mothers to their neonates was elucidated using the Malassezia microbiota as an indicator. METHODS: Temporal changes in the level of Malassezia colonization of the skin from 27 neonates and mothers were investigated by real-time polymerase chain reaction assay. The genotypes of Malassezia colonizing the neonate and mother were also determined. RESULTS: Malassezia was detected from 89% and 100% of neonate samples on days 0 and 1 after birth, respectively. Subsequently, the level of Malassezia colonization of the neonates increased with time, whereas that of the mothers did not change. The Malassezia diversity of neonates shifted to the adult type by day 30. The genotype of Malassezia colonizing the skin of neonates agreed well with that of Malassezia colonizing the skin of the mothers. CONCLUSION: Fungal microbiota colonization of neonates began on day 0, and the fungal microbiota of neonates had changed to the adult type by day 30. To our knowledge, this is the first report of a molecular analysis of the fungal microbiota of neonates.

[Dermatomycoses due to pets and farm animals : neglected infections?]. / Dermatomykosen durch Haus- und Nutztiere : Vernachlässigte Infektionen?

Dermatomycoses due to contact with pets and livestock frequently affect children and young adults. Zoophilic dermatophytes are the main important causative agents. It has long been known that the often high inflammatory dermatophytoses of the skin and the scalp are caused mostly by Microsporum canis. Due to an absence of an obligation for reporting fungal infections of the skin to the Public Health Office in Germany, an unnoticed but significant change in responsible pathogens has occurred. Today an increasing number of infections due to zoophilic strains of Trichophyton interdigitale (formerly Trichophyton mentagrophytes) and Trichophyton species of Arthroderma benhamiae are found. The latter mentioned dermatophyte is the anamorph species of the teleomorph Arthroderma benhamiae, which originally was isolated in the Far East (Japan). Source of infection of these dermatophytes are small rodents, in particular guinea pigs. These animals are bought in pet shops by the parents of those children who later are affected by the fungal infection. The coincidental purchase of the relevant fungal pathogen is not obvious to the parents. As a consequence, highly contagious dermatophytoses occur, often tinea capitis sometimes with kerion formation. Further dermatophytes should be considered as cause of a zoophilic dermatomycosis. Both Trichophyton verrucosum, the cause of the ringworm in cattle, and Trichophyton erinacei following contact to hedgehogs are worthy of note. Yeasts cannot be ignored as cause of dermatomycosis, especially Malassezia pachydermatis, the only non-lipophilic species within the genus Malassezia, which can be transferred from dog to men. Cryptococcus neoformans also comes from animal sources. The mucous yeast occurs in bird's dropping, and it causes both pulmonary and central nervous system infections, but also primary and secondary cutaneous cryptococcosis in immunocompromised patients (HIV/AIDS) as possible consequence after contact to these animals.

Dermatophytes as a cause of epizoonoses in dairy cattle and humans in Iran: epidemiological and clinical aspects.

Zoophilic dermatophytosis is a major public and veterinary health problem globally widespread among cattle. To identify the causative agent and geographical distribution of dermatophytes involved in cattle ringworm and to establish if they would be related to human diseases in Iran, a study was carried out on 6789 heads of cows and 130 herdsmen during 2006-2007. Samples were taken from 380 cattle and 43 herdsmen with suspected dermatophytosis. The causative agents were identified macroscopically and microscopically by KOH examination and culture isolation. Only 352 cases of dermatophytosis were identified in cattle and Trichophyton verrucosum was the exclusive fungus isolated from animals. Moreover, 27 cases of human dermatophytosis were identified and T. verrucosum was the prevalent causative agent for dermatophytosis in the body, scalp, foot, nail and groin of the patients. The obtained results showed that T. verrucosum was the predominant cause of dermatophytosis in livestock and dairy farmers. There is a scarcity of information on isolation and identification of the epizoonotic agents of dermatophytoses in cattle in Iran. This study showed the occurrence of dermatophytosis in humans and cattle and confirms that the dermatozoonoses are responsible for predominant forms of the disease in people who were in contact with cattle.

A zoonotic ringworm outbreak caused by a dysgonic strain of Microsporum canis from stray cats.

BACKGROUND: Cats are frequent carriers of Microsporum canis and veterinary students are at high risk of exposure and acquisition of the organism a la infección. OBJECTIVES: An outbreak of zoonotic ringworm carried by a litter of stray cats is described. Four veterinary students, four dogs, and six cats living in five separate locations were affected. All had direct or indirect contact with the infected kitten litter. We tried to identify the causal dermatophyte. METHODS: Conventional and mycological culture methods were used. RESULTS: Microscopic features of scrapings and hairs treated with 20% KOH strongly suggested a M. canis etiology, and a diagnosis of ringworm was empirically supported by successful treatment of humans and animals. Nevertheless, cultures failed to show the expected morphology. CONCLUSIONS: Culture features of our strain are compared with those described by other authors for dysgonic M. canis strains. Epidemiological features are also discussed.

Trichophyton erinacei infection from a hedgehog: a case report from Taiwan.

Trichophyton erinacei is a fungus affecting hedgehogs. As these animals have become popular as exotic pets, human infections with this organism have been documented in many countries. In Taiwan, a 36-year-old woman developed tinea lesions at multiple sites after carrying a sick hedgehog. The animal subsequently lost its quills and died. On culture of the patient's skin scrapings, the pathogen was identified mycologically as Trichophyton erinacei, which was confirmed by sequencing of the internal transcribed spacers of the fungal nuclear ribosomal DNA. The same fungus was isolated from the sawdust bed previously used by the diseased hedgehog. A careful contact history is important for identifying this emerging zoonosis.