The role of the National Institute of Public Health in the field of infections with natural focality.

In the post-war period the National Institute of Public Health, later Institutes of Epidemiology and Microbiology, headed by K. Raska, ranked among famous laboratories in the world due to its priority findings and original results. Research results of the Institute stimulated further research not only in Czechoslovakia but also abroad, in laboratories of Europe and America. The authors emphasize the significance of certain results in the epidemiology and ecology of infections characterized by natural focality. In the first place they discuss the isolation of TBE in 1948 and 1949 by Gallia et al., and the study of the role of birds and bats as hosts of TBE. Significant for the recognition of zoonotic influenza viruses are papers by Tumová, and as regards rabies in rodents the studies of Sodja et al. The institute paid attention to the introduction of Coxiella burnetii into the north-west of Bohemia. The institute's activities in the study of tularaemia, leptospirosis, Lyme borreliosis, and toxoplasmosis are also described. Raska's concept of epidemiological surveillance in the prevention of zoonoses with natural focality was fully enforced by workers of the institute. Many results of the Institute have been adopted by the WHO; it was demonstrated that it is possible by appropriate methods not only to detect human diseases in places where they are known but also to discover them in nature extensively altered by man.

Salmonellae in gulls and other free-living birds in the Czech Republic.

Cloacal swabs, collected from 756 wild synanthropic and exoanthropic birds of 57 species in the Czech Republic, yielded 32 strains of Salmonella typhimurium [phage types (PT) 141, 104 and 41], six isolates of S. enteritidis (PT 8, 4 and 6e), and one each of S. panama and S. anatum. Except for one S. enteritidis isolate from a grey-lag goose (Anser anser) and one S. typhimurium isolate from a coot (Fulica atra), all of the other strains were derived from black-headed gulls (Larus ridibundus), of which 24.7% were found to be infected. The black-headed gull might play a role in the dispersal of pathogenic salmonellae.

[Urban cycles of zoonotic mycoses]. / Urbánní cykly nekterých mykóz zoonotického charakteru.

Based on their own results assembled during mycological examinations of 9958 subjects, 5496 animals and 648 specimens of non-animal substrates, and using data from the literature, the authors tried to formulate general laws concerning the prevalence of causal agents of mycoses with a zoonotic character which circulate steadily in urban areas: Microsporum canis, M. persicolor, Trichophyton mentagrophytes, M. equinum and T. equinum, T. verrucosum, some geophilic dermatophytes, Cryptococcus neoformans and Emmonsia crescens. In the characteristics of different urban cycles they used as a basis the evaluation of the prevalence of reservoir animals and reservoir substrates on the territory of towns and the evaluation of the most frequent routes of transmission of the agents from extrahuman sources to man. Preventive provisions leading to a reduction of the risk of the disease in humans must be specific with regard to different urban cycles.

[Natural foci of Lyme borreliosis]. / Prírodní ohniskovost lymské borreliózy.

The submitted paper provides evidence that tick-borne borreliosis described as Lyme disease, is a disease with natural focality. Its properties, despite the widespread occurrence, classify it in this group. The authors give a characteristic of the disease, of hitherto known vectors, the main reservoir animals in America and Europe. Attention is drawn to the importance of deer and the effect of their increasing numbers on the spread of ticks and the disease. The great adaptability of the causal agent is apparent from the wide areas of its occurrence, incl. the Holoarctic, Aethiopian and Australian area. The complicated relations of the natural foci of tick-borne borreliosis must be investigated in particular under Central European conditions.

Growth and bone maturation in children from two regions of the F.R.G. differing in the degree of air pollution: results of the 1974 and 1984 surveys.

Growth and bone maturation criteria were used in this collaborative study to assess the potential health risk posed by excessive air pollutant emission. The study consisted of two surveys carried out 10 years apart. During this decade, a substantial emission reduction through the effective control efforts was achieved in the index area, but not so in the reference area where the situation remained virtually unchanged during this period. In terms of body height and height-weight proportionality, no significant differences were found between areas and years of investigation. In contrast, the bone age retardation encountered in the children from the polluted area was statistically significant, both at 1974 and 1984 surveys, despite the appreciable improvement in this developmental criterion for boys in 1984. This was true for both group mean values and the percentages of individuals exhibiting the bone maturation delay greater than 10 months.

Fungi from interior organs of free-living small mammals in Czechoslovakia and Yugoslavia.

A total of 308 fungi was isolated from interior organs (lungs, spleen, liver) of 529 small mammals belonging to 21 species, 7 families and 3 orders (Insectivora, Chiroptera, Rodentia), some of these being potentially pathogenic to vertebrates (e.g. Aspergillus flavus, A. fumigatus, Geotrichum candidum, Mucor pusillus, Rhizopus arrhizus). In one vole (Microtus arvalis) captured in South Moravia, adiaspiromycosis (Emmonsia crescens) was demonstrated. Comparison of mycoflora of hair and that of interior organs of wild small mammals revealed that out of the total number of isolates the following fungi were represented in a higher proportion from visceral organs than from the hair: Aspergillus (A. amstelodami, A. flavus, A. repens), Aureobasidium (A. pullulans), Candida, Cladosporium (C. herbarum), Cryptococcus, Fusarium, Gliocladium (G. deliquescens), Helminthosporium, Kloeckera, Mucor (M. fragilis, M. hiemalis, M. pusillus), Paecilomyces marquandii, Penicillium (P. purpurogenum), Phoma, Rhizopus arrhizus, Scopulariopsis (S. candida, S. koningii) and Torulopsis.

A proposal for the evaluation of vertebrates as to their role in the circulation of arboviruses.

The authors present a proposal for the classification of vertebrates as hosts or hosts-amplifiers of arboviruses from an ecological point of view.

Mammals as source of ectoparasites in towns.

Four ecological groups of mammal ectoparasites are recognized in urban environment and their medical importance is briefly mentioned.

Some ecological criteria of natural focality of mycotic zoonoses.

Mycotic zoonoses sensu stricto and mycotic infections acquired from animal polluted environment belong to diseases characterized by the phenomenon of natural focality. On a global scale they comprise 16 different diseases caused by yeast-like organisms, dematophytes, dimorphous agents of systemic mycoses and primarily saprophytic fungi as well. Prevalence of mentioned diseases is influenced by a number of factors concerning not only biology and ecology of pathogenic agents and particular hosts, but also character of specific extra-animal substrates which make possible long-term maintenance or active propagation of agents in the environment. On the basis of their experience and published data as well, the authors present a survey and analysis of these factors, with particular emphasis on very frequent dermatophytozoonoses and some systemic mycoses. They pay attention to different conditions in urbanized and rural areas and to specific situations encountered by man and food producing animals in these areas. They note different ways of heterotrophy of particular agents and their association with vertebrate hosts which they divide into six ecologically different groups. The authors also characterize the environment in which a portion of saproparatrophic circulation of the agent takes place. They also give a survey of animal-connected human mycoses, which may arise due to occupational hazards.