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71.
Haemophilus parasuis causes Glässer''s disease, a syndrome of polyserositis, meningitis, and arthritis in swine. Previous studies with H. parasuis have revealed virulence disparity among isolates and inconsistent heterologous protection. In this study, virulence, direct transmission, and heterologous protection of 4 isolates of H. parasuis (SW114, 12939, MN-H, and 29755) were evaluated using a highly susceptible pig model. In an initial experiment, isolates 12939, MN-H, and 29755 caused Glässer''s disease, while strain SW114 failed to cause any clinical signs of disease. One pig from each group challenged with MN-H or 29755 failed to develop clinical disease but was able to transmit H. parasuis to noninfected pigs, which subsequently developed Glässer''s disease. Pigs colonized with SW114, 29755, or MN-H that were free of clinical disease were protected from a subsequent challenge with isolate 12939. In a following experiment, pigs vaccinated with strain SW114 given as either a bacterin intramuscularly or a live intranasal vaccine were protected from subsequent challenge with isolate 12939; however, some pigs given live SW114 developed arthritis. Overall these studies demonstrated that pigs infected with virulent isolates of H. parasuis can remain healthy and serve as reservoirs for transmission to naive pigs and that heterologous protection among H. parasuis isolates is possible. In addition, further attenuation of strain SW114 is necessary if it is to be used as a live vaccine.  相似文献   
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Offering rapid HIV testing improves rates of testing in adults, but little is known about whether offering adolescents a choice of testing methods increases rates of testing. The aims of the study were to determine rates of HIV testing in adolescents when different testing methods were offered and explore factors associated with agreement to be tested for HIV. Participants (n= 200, sexually experienced 13-22 year olds) were recruited from an urban adolescent clinic, completed a 99-item theory-based survey and were offered their choice of venipuncture, rapid fingerstick or rapid oral fluid HIV testing. Approximately half (49.5%) agreed to HIV testing. Male gender, parental completion of high school, intention to test for HIV if offered by clinician and higher perceived likelihood of current HIV infection were independently associated with agreement to test. Combining new strategies, such as opt-out testing, with routine testing may be needed to improve rates of adolescent HIV testing.  相似文献   
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Background

Legal regulations concerning infection protection have been repeatedly revised in the last few years. At the national level the regulations for notifable diseases were recently broadened to include the suspicion of disease, the disease and death due to mumps, pertussis, rubella including congenital rubella and varicella (chickenpox). In addition notification deadlines were shortened in the new regulations and the information to be reported was expanded. At the “Bundesländer” level, there are also new regulations which expand notification concerning diseases and are extended to other contagious diseases. In addition, infection protection also includes measures to prevent and combat contagious diseases.

Objective

This article describes the current legal situation.  相似文献   
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