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Serological investigations in Nigeria for anthropozoonoses in human sera: brucellosis, echinococcosis, toxoplasmosis, chlamydial diseases, listeriosis, rickettsiosis (Coxiella burneti and Rickettsia conori).

176 blood sera taken from patients in the hospital of Minna and Abeokuta (Nigeria) were examined for anthropozoonoses. The following positive reactions could be found: Brucella abortus 9%, Brucella melitensis 11.7%, Echinococcosis 0.53%, Toxoplasmosis 79.2% (CF-Test 6.9%), Chlamydial diseases 45%, Listeriosis 28.7% (Typ 1H) and 19.7% (Typ 4bH), Rickettsiosis--Rickettsia conori 18.6% and Coxiella burneti 63.3%.

Antibodies, Bacterial↗

Study of rickettsioses in Slovakia. II. Infestation of fleas and mites in mole nests in some localities in Central Slovakia with C. burneti and Rickettsiae belonging to the spotted fever (SF) group.

Fleas and mites obtained from 115 mole nests in Central Slovakia from an area where Q fever and rickettsiosis due to rickettsie of the SF occur, from the border of this area and apart from it, were tested for infestation with rickettsiae by the method of isolation of rickettsiae on chick embryo yolk sacs, by the method of detection of rickettsiae on smears from the arthropods using immunofluorescence, by the method of exposure of albino mice and Apodemus flavicollis to mole nests and by the method of inoculation of suspension from the arthropods to albino mice. In the latter two methods, infestation of the arthropods was assessed according to the formation of antibodies in the mice. It has been found that fleas and mites in all three areas under test are infected with C. burneti and with rickettsia of the SF group. C. burneti was currently detected in the focus of rickettsioses and in the localities situated in its borders while only one case was observed apart from the focus. Rickettsiae of the SF group were found in fleas and mites in all areas tested showing no greater percentual differences. The method of detection of rickettsia in smears from the arthropods using the immunofluorescence technique and antibody response in mice inoculated with infected arthropods was found to be the most effective in these studies. On the basis of the obtained results the authors believe that mites and fleas living in mole nests participate in the circulation of both species of rickettsiae in nature in the transfer of rickettsiae among small mammals. The question whether these arthropods are a reservoir, a biological or a mechanical vector, still remains open.

Animals↗

[Experimental Q-rickettsiosis in lambs].

The clinical course, serologic response, and morphologic changes were followed up in month-old lambs infected nasally and via the trachea with Rickettsia burneti at the rate of 10,000 ID50/cm3. Rickettsiae were found in the parenchymal organs, the blood clot, the nasal cavity, the trachea, and the feces of the animals killed on the 7th and 21st day of infection. Complement-fixing antibodies were established in the infected lambs with the use of the complement-fixation test from the 5-6th up to the 160th day (period of testing), the highest value of the titer (1:160) being observed on the 32nd day. Demonstrated were changes in the vessels, and degeneration was found in the liver, kidneys, and other viscera along with proliferative changes in the spleen. Guinea pigs and albino mice were successfully made use of to isolate Rickettsia burneti from the infected parenchymal organs, feces, and others of affected lambs.

Animals↗

[Current data on the polymorphism of Rickettsia prowazekii and burneti in cultured cells].

In cultivation of Rickettsia prowazeki (strains Breinl and E) in the cell cultures of guinea pig kidneys (GPK) and chick embryo fibroblasts (CEF) ultrastructure of rickettsia of unusual shape (filamentous, irregularpleomorphic and spheroplast-like) were revealed along with rickettsia of the usual shape and size. The polymorphism was less pronounced in the GPK and the CEF cells of Rickettsia burneti (strain M-44). It is supposed that rickettsial polymorphism was not associated with their developmental cycle and served as a morphological expression of the changes in the microorganism under the effect of unfavourable ecological conditions. The appearance of filamentous forms could be associated with disturbed cell division process; changed rigidity of the cell wall could serve as the cause of appearance of pleomorphic rickettsia. In difference from polymorphism, the cycle of rickettsial development is considered to be (in the basis of modern electron microscopic data) as a biological replacement of the vegetative (rod-like, bacillary) forms by those more stable in the external environment, resting (coccoid).

Animals↗

Study of rickettsioses in Slovakia. I. Coxiella burneti and Rickettsiae of the spotted fever (SF) group in ticks and serological surveys in animals and humans in certain selected localities in the Lucenec and V. Krtís districts.

A study of the natural focus character of Q fever and the rickettsiosis caused by organisms of the SF group carried out in 1971-1973 in 7 selected villages in the Lucenec district and in a few control villages in the V. Krtis district, produced the following results: Among a total number of 2,200 ticks belonging to the species Dermacentor marginatus, Ixodes ricinus and Haemaphysalis punctata and tested for the presence of rickettsial organisms by the haemocyte test, C. burneti was detected in 8 from the chosen localities--in 2 females and 1 male of D. marginatus in Luborec, in 1 2. ricinus female in Maskova and in 1 female and 3 males of I. ricinus in Pincina--and in 5 from the control localities--in 1 D. marginatus female in Prebelce and in 3 females and 1 male of D. marginatus in V. Lom.

Animals↗

Electron microscopy studies of the limiting layers of the rickettsia Coxiella burneti.

Surface layers of Coxiella burneti studied at a high resoulution reveal a plasma membrane and an outer surface membrane 6 to 7 nm thick, and a thin, moderately electron-dense intermediate layer associated with the inner surface of the outer membrane of many cells. This layer appears to be unaffected by lysozyme treatment. Ruthenium red staining was used to delineate a layer of filamentous material external to the outer membrane; this fuzzy layer has a mean thickness of 20 nm and is not often seen on the surface of cells prepared by conventional means. Both antigenic phase I and II cells show a ruthenium red-binding surface layer. It is suggested that this fuzzy layer may be, among other possibilities, a highly branched mucopolysaccharide.

Animals↗

Clinical, virological, and pathological findings in a fatal case of Q fever endocarditis.

A case resembling subacute bacterial endocarditis in which blood cultures were repeatedly negative is described. The patient had had an influenza-like illness nine months before admission to hospital followed by intervening vague illness and loss of weight. Serological tests revealed a high titre of complement-fixing antibodies to phase 1 and phase 2 antigens of Rickettsia burneti. After death R. burneti was isolated from the diseased aortic valve, liver, and kidneys. Bodies morphologically resembling rickettsiae were seen in the aortic valve and in a very few renal tubule cells. No specific pathological lesions were found but there was a widespread stimulation of reticulo-endothelial cells particularly in the aortic valve cusps, spleen, lymph nodes, and renal glomeruli. It is suggested that tests for Q fever should be carried out in suspected cases of subacute bacterial endocarditis when blood culture is negative.

Aortic Valve↗