Lucille K. Georg

A case of phaeohyphomycosis caused by a new species of Phialophora.

A subcutaneous fungus infection that developed in a kidney transplant patient on immunosuppressive maintenance therapy was found to be caused by a new species of Phialophora. This species, P. paras...

In vitro hair cultures for differentiating between atypical isolates of Trichophyton mentagrophytes and Trichophyton rubrum.

Isolates ofT. mentagrophytes andT. rubrum are encountered that cannot be distinguished from each other solely on the basis of morphological criteria. Since these two species fundamentally differ in the manner in which they attack hairin vitro, this property can be used as a diagnostic aid, when correlated with their morphologic characteristics as developed on a variety of media. T. mentagrophytes radially penetrates hair segments immersed in water forming wedge-shaped perforations.T. rubrum does not perforate hair. The method of determining the ability or inability ofT. mentagrophytes orT. rubrum to perforate hair and the use of this test in identifying those species are described.Isolates ofT. mentagrophytes andT. rubrum are encountered that cannot be distinguished from each other solely on the basis of morphological criteria.

A new species of Microsporum pathogenic to man and animals

A new dermatophyte species, Microsporum vanbreuseghemii, is described. This fungus was isolated from ringworm of a Malabar squirrel, a dog, and 2 human beings. The fungus is characterized by the development of many large, thick-walled, echinulate, cylindro-fusiform macroconidia. Cleistothecia with ascospores were produced by all strains when grown on hair on the surface of soil. It is proposed that the perfect form of M. vanbreuseghemii be included in the genus Nannizzia as N. grubyia sp. nov.

RECENT DEVELOPMENTS IN ANIMAL RINGWORM AND THEIR PUBLIC HEALTH IMPLICATIONS

The ability to break down keratin is an important characteristic of the dermatophytes. In vioo, these fungi are parasites of the keratinized tissues of the body, such as the epidermis, the hair, and the nails, and they produce alterations of the structures invaded. These alterations, together with attendant immunological reactions, are clinically classified as ringworm. Both man and the lower animals are susceptible to infection by ringworm fungi. However, the individual dermatophyte species show varying degrees of host specificity. Some are parasites of man, and these rarely, if ever, infect lower animals; others are primarily animal pathogens that are found to produce human disease on occasion. Thus, on the basis of host preference or host adaptation, the ringworm fungi have been divided into two groups. In one category have been placed the human pathogens or anthropophilic organisms and, in the other, the animal pathogens or zoophilic dermatophytes. While it is true that some of the human and animal pathogens have been recovered from the contaminated environment of infected hosts1e3 such apparent saprophytism appears to be secondary to their parasitism of man or animals. Until recently, nearly all of the known dermatophytes have been placed in one or the other of these two groups. Recent findings, however, point to the necessity of establishing still another category of dermatophytes, one that would draw its members from among the keratinophilic soil-inhabiting fungi that have the ability, under certain conditions, to invade the keratinized tissues of human and animal hosts and there to produce disease. Members of this group are essentially saprophytes and, probably, serve along with other keratinophilic organisms in the microbiological breakdown in soil of keratin into simple Plements. To date, only two species, Microsfiorum gypseum4j u and Keratinomyces ajelloi6-8 have been demonstrated to belong in this third category. Thus, from an epidemiological standpoint it is logical, a t this time, to consider the existence of these three groups of ringworm fungi: the anthropophilic or “human-type” organisms, the zoophilic or “animal-type” organisms, and the “geophilic” or soil organisms. hiembers of the three groups of dermatophytes are involved in human disease, and each type presents distinct public health problems. As might be anticipated, the vast majority of ringworm infections in man are caused by anthropophilic organisms. Such conditions as “athlete’s foot,” and ringworm of the groin and nails are comrnon conditions affccting large segments of our population. They are caused by anthropophilic dermatophytcs, and animals have not been shown to play a role in the cpidemiology of thcse diseases. IIowever, if one excludes these common infections and considers only ringworm of the exposed parts of the body, such as the scalp, face, neck, and extremities, then the zoophilic organisms appear as important contributors to human

Epidemiology of the dermatophytoses sources of infection, modes of transmission and epidemicity.

The dermatophytes and the diseases that they produce may be divided into several groups on the basis of sources of infection, host preference, and epid emici ty . As might be expected, human infections in rural areas are commonly acquired from domesticated or wild animals. Such infections usually evoke considerable tissue reaction in the host, and are characterized by suppuration, kerion formation, and allergic phenomena that appear to be responses to fungi not well adapted to existence in human tissues. Until recently, we have had little knowledge of the prevalence of ringworm infections of animals or information regarding the frequency of their transmission to humans. In the past few years, however, several epidemiological studies and surveys such as those conducted in England by Ainsworth and Austwick,l La Touche: Gentles and O’S~llivan,~ and McPher~on,~ in Yugoslavia by Oiegovit and Grin,6s6 and in the United States by the Communicable Disease Center in Atlanta, Ga.,7*s have been carried out. The results of these studies have shown the high prevalence of ringworm in animals and have given considerable evidence on the manner in which these infections are transmitted to humans. The individual dermatophyte species have varying degrees of host specificity, These are the so-called zoophilic fungi. Although animals appear to be the natural hosts for this group of fungi, such infections frequently are transmitted to humans. Six dermatophyte species that commonly cause ringworm in animals have been found to be important in relationship to human infection. These include Microsporum canis, M . distortum, Trichophyton verrucosum, T . mentagrophytes (var. granulare), T. equinum, and T. gallinae. Human infections due to M . canis are common in both rural and urban communities, and there is little doubt that most cases are of animal origin. This fungus is the most common cause of ringworm in cats and dogs. I n the Communicable Disease Center survey, 325 feline specimens yielded dermatophytes. Of these, 318 or 97.8 per cent were M . canis. Of 495 canine specimens, 329 or 66.5 per cent were M . canis. Cats and dogs appear to be the most important source of M . canis infections in man. Human infections due to T. verrucosum are confined almost entirely to the rural population. This fungus causes the vast majority (98 to 100 per cent in Some areas) of ringworm infections in cattle.4vs Most human infections are easily traced to direct contact with ringworm-infected ~ a t t l e . ~ ’ ~ A number of cases of indirect transmission have been reported als0.1iJ3J4 In some instances it appears that infected cattle hairs have been carried on the clothing of the farmer into his home where children, including infants, have become infected indirectly.” WalkerI5 has shown that T. verrucosum remains viable on

Rothia, gen. nov. an aerobic genus of the family Actinomycetaceae

SUMMARY Rothia gen. nov. (Actinomycetaceae) is proposed as the name of a monotypic genus with the species Rothia dentocariosus comb. nov. (basionym Actinomyces dentocariosus Onisi 1949), synonyms Nocardia dentocariosus (Onisi) Roth 1957; Nocardia salivae Davis and Freer 1960, No strain of Onisis original isolates is extant. ATCC 17931 is described and proposed as the neotype strain of Rothia dentocariosus (Onisi) Georg and Brown 1967.

Odontomyces viscosus, gen. nov., spec. nov., a filamentous microorganism isolated from perio-dontal plaque in hamsters

It is proposed that a new genus, Odontomyces, with Odontomyces viscosus as the type species, be created for the organism previously described from plaques from spontaneous periodontal disease in hamsters. Odontomyces viscosus should be placed in the Actinomycetaceae.

Encephalitis in Turkey poults due to a new fungus species

A dematiaceous fungus, Diplorhinotrichum gallopavum sp. nov. is described as an agent of encephalitis in young turkey poults. In the outbreak described, at least 600 poults, of a flock of 4,000, were affected. The infection was proven by isolation of the fungus from the brains of 9 of the turkey poults, and by demonstration of dematiaceous mycelium in the brain tissue. The disease was probably acquired through contact with old sawdust used as litter for the birds. Attempts to reproduce the disease experimentally failed.

Trichophyton equinum var. Autotrophicum; Its characteristics and geographical distribution

“As for the horse, it appears to be one of the animals most often afflicted with ringworm, and the variety of them is nearly as great as that of ringworms of man”             (Sabouraud, 1903)The morphological and nutritional characteristics and experimental pathogenicity of typical nicotinic-acid requiring strains of Trichophyton equinum were compared with atypical nonnicotinic acid strains from New Zealand and Australia. Apart from this nutritional dependancy and slight variations in reverse pigmentation, both types were similar. Under the conditions of our experiments, atypical strains produced larger lesions in horses than did typical strains of T. equinum but the difference was not useful diagnostically. Infections with either the nicotinic acid requiring or the non-requiring strains resulted in resistance to re-infection with both the homologous and heterologous variety. The atypical strains have been named Trichophyton equinum var. autotrophicum to indicate their less exacting nutritional requireme...

The Relation of Nutrition to the Growth and Morphology of Trichophyton Violaceum. I. The Vitamin and Amino Acid Requirements of T. Violaceum

SUMMARY1. T. violaceum grows slowly and poorly on Sabourauds dextrose agar. The colonies are usually small, and glabrous, and consist of a mass of poorly developed mycelium and chlamydospores.2. O...