Comparison of virulence for guinea pigs and mice of different Coxiella burnetii phase I strains.

Virulence of four Coxiella burnettii phase I strains associated with acute (Nine Mile and Luga strains) and chronic (S and Priscilla strains) forms of Q fever, respectively, for outbred guinea pigs and inbred BALB/c mice was compared. In guinea pigs exposed to infectious aerosol, virulence of the strains Nine Mile, Luga and S was similar, because they all caused lethal infection and high febrile reaction (FR). By contrast, exposure to similar doses of the strain Priscilla resulted in the non-lethal infection manifested only by low, dispersed and protracted FR during a 20 day-period of observation.

[Clinical and serologic study of Czecho-Slovak citizens working in developing countries from the aspect of risk of infection with Coxiella burnetii].

In the years 1984-1988 we observed, besides the routine examinations of history, clinical state, and laboratory tests, also the presence of antibodies to Coxiella burnetii antigens by means of microagglutination reaction (MAR). The examinations were performed in our citizens returning to Czecho-Slovakia from a long termed business stay in the developing countries. Antibodies to C.

Immunoblot analysis of antibody response in mice infected with Coxiella burnetii phase I.

Mouse sera collected from day 4 to day 133 postinfection (p.i.) with phase I Coxiella burnetii strain Nine Mile were analysed by immunoblotting with phase I C.

Control of rickettsial diseases.

Prevention of rickettsial infections is aimed at individual control and epidemic measures (especially in epidemic typhus), vector and rodent control, milk pasteurization (in Q fever), chemoprophylaxis and immunoprophylaxis. In vector and rodent control, the main obstacle is the rise in resistance to insecticides and rodenticides. For this reason in vector control, apart from insecticides, enhancement of the natural immunity acquired by animals in response to tick infestation and vaccination with concealed tick antigens as well as the use of hormones, chemosterilants and genetic manipulation can also be considered.