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The results briefly presented here highlight some of the observations met with during the course of a study aimed at finding out differential pathogenic behavior of the two strains of Cryptococcus neoformans i.e. W71/A117 and W2/A94 with special reference to cryptococcoma formation. Both strains were isolated from bird excreta but differed in their gross and microscopic morphology. Groups of male albino mice NMRI were separately inoculated, intramuscularly, with a comparable dose of the two strains. All the 50 animals challenged with W71/A117 developed macroscopically distinct cryptococcoma of variable size, and fatally progressive disease, involving most of the internal organs, namely, brain, heart, lung, liver, spleen and kidneys. On the contrary, only 34 of the 50 mice infected with the strain W2/A94 showed cryptococcoma formation at the site of inoculation, which were comparatively much smaller in size and gradually diminished. None of the animals, observed over a period of 93 days, died, and showed any sign of metastasis. In another series of experiment, only one instance of mortality was observed in a group of 80 mice inoculated intraperitoneally with about 2 X 10(7) viable cells of this strain. However, the fungus could be recovered, in a majority of cases, only from the brain of animals sacrificed after one month, though most of them showed no sign of sickness. The number of mice yielding positive cultures gradually decreased, and after 87 days the fungus could not be isolated from any organ. The high morbidity and mortality in mice caused by strains W71/A117 was significantly lowered when the animals were infected intramuscularly 3 months ago with the strain W2/A94. After an observation period of 61 days, 91% of the double infected animals were still alive in comparison to 23% survival among the animals challenged with the strain W71/A117 only.

In an 8-year-old girl with cystic fibrosis Aspergillus fumigatus infection of the lung was diagnosed. Pot-plant soil as reservior of Aspergillus fumigatus was shown to be the source of inhalable Aspergillus fumigatus units within the clinic. Cystic fibrosis mucus of the patient acted as nutritive substrate for Aspergillus fumigatus. Consequent exclusion of pot plants in housing and hospital rooms is considered necessary for prevention of Aspergillus fumigatus infection in patients with cystic fibrosis.

The incidence and distribution of aspergillosis among patients of a lung clinic in West Berlin were recorded. The immunodiffusion test (IDT) was used on sera of 228 patients seen during one day to test for precipitins against A. fumigatus, A. flavus, and A. niger. Precipitating antibodies specific against A. fumigatus were found in five patients, in two of them A. fumigatus was isolated simultaneously from sputum. In order to obtain a clear view of the clinical occurrence of asperigillosis and its course one requires not only serological tests but also the isolation of Aspergillus in culture from sputum or bronchial secretion. IDT is useful for detecting aspergillosis and for screening persons harbouring Aspergillus in their respiratory tract.

Twenty-eight out of 30 patients suffering from denture-wearer's stomatitis, yielded yeast-like fungi from the areas of inflammation. The fungi included Candida albicans (20), Torulopsis glabrata (7), C. tropicalis (3), C. pseudotropicalis (1), and C. krusei (1). In 15 cases, a heavy fungal growth was found. Of the 20 C. albicans strains, 18 exhibited an extra-cellular proteolytic activity on Serum-Albumin agar with the initial pH value of 5.0. In the sera from 20 patients, precipitating antibodies against C. albicans antigens were detected with the help of the immunodiffusion test. The haemagglutination test revealed titers greater than or equal to 1:160 in 18 cases. The questionable pathogenic significance of the yeast-like fungi in the denture wearer's stomatitis is discussed.

The increasing incidence of human A. fumigatus infections particularly such of the respiratory tract has led to this study of the epidemiological situation. During the period between October 1968 and December 1977, A. fumigatus was isolated from clinical material in 425 cases. These findings which were established at the Mycology Unit, Robert Koch Institute, Federal Health Office, exhibited the following distribution by regions of the body or type of specimen: respiratory tract 277 (65.1(); venous blood 58 (13.6%); urine 3 (0.7%); stools 9 (2.1%) and others 78 (18.3%). Approximately two thirds of these findings were made during the period from October to March and about one third between April and September. The presence of A. fumigatus in the air both indoors and outdoors and also in the environment of patients suffering from aspergillosis was studied with the aid of the sedimentation-method. This method was chosen because the occurrence of A. fumigatus conidia in the air is of epidemiological interest. The number of isolations of A. fumigatus from outdoors samples was low, so the search for inhalative conidia concentrated upon sites near A. fumigatus habitats. These studies revealed that aspergillosis patients, clinical material sampled from them, decaying plant material (agriculture, horticulture), and used clothes and linen may form foci for the spread of A. fumigatus conidia. The control of aspergillosis in the hospital environment involves in particular a control of aspergillosis patients by means of culture and serology (preferably by ghe immunodiffusion test). Numerous recommendations are made on how to prevent A. fumigatus infections in hospitals, at the working site, and in the laboratory.