Please read the abstract in the section 00front of this document / Thesis (PhD (Microbiology))--University of Pretoria, 2007. / Microbiology and Plant Pathology / unrestricted

Please read the abstract in page 85 of the document. / Thesis (DVSc)--University of Pretoria, 1960. / Paraclinical Sciences / DVSc / Unrestricted

B. abortus is an intracellular facultative bacterial pathogen which causes abortion in cattle and undulant fever in humans. Cattle vaccines such as B. abortus strains 19 and RB51 are live vaccine strains which protect approximately 75% of the vaccinated animals. No effective vaccines are available for the prevention of brucellosis in humans. We are developing vaccinia virus recombinants expressing various B. abortus proteins to prevent brucellosis in susceptible mammalian species. In this work the B. abortus groEL gene encoding the antigenic heat shock protein GroEL was subcloned into vaccinia virus via homologous recombination. Expression of the GroEL protein in vaccinia infected cells in-vivo was confirmed by immunoblotting. Groups of 5 female BALB/C mice were injected with the vaccinia recombinant or appropriate positive and negative control vaccines. Mice were bled and their humoral immune responses assessed. In addition, mice were challenged with virulent B. abortus strain 2308 and protection measured by the rate of splenic clearance of live Brucella. In spite of demonstrating specific GroEL antibodies in recombinant vaccinia injected mice, no significant level of protection was demonstrable. Preliminary lymphocyte transformation assays were carried out to establish if a cell mediated immune response to GroEL was induced in the vaccinated animals. / Master of Science

Diss. (sammanfattning) Stockholm : Karol. inst., 2003. / Härtill 5 uppsatser.

Thesis (D.P.H.)--University of Michigan.

Thesis (D.P.H.)--University of Michigan.

Dissertation (D.P.H.)--University of Michigan.

Dissertation (D.P.H.)--University of Michigan.

Over 80% of the newly emerging infectious diseases are caused by RNA viruses. Major global problems associated with the development of vaccines against the RNA virus are their high genetic and antigenic diversity. Hence, effective control of epidemics with newly emerging RNA viruses require improved vaccines which are either specific to the new strain or broadly effective even when new viral strains emerge. The main focus of this dissertation is to develop epidemic vaccines using these two approaches. Using a newly emerged swine enteric virus called porcine epidemic diarrhea virus (PEDV) as a model, our first goal was to develop a quick and easy method for rapid response vaccines with potential applicability to a range of RNA viruses. We hypothesized that the methods which can disrupt genomic RNA without impacting the structural integrity of the virus would result in attenuated vaccine with minimum replication in the host while inducing immune responses. As hypothesized, developed rapid response PEDV vaccine induced complete protection against the virulent challenge virus, while vaccine viral shedding was not detected in vaccinated pigs. To address the second problem of rapid viral evolution leading to vaccines becoming obsolete, we used swine influenza virus (SIV) as a model to develop and test a universal vaccine composed of peptides encoding conserved antigenic epitopes which are present in most influenza A viruses. Importantly, a novel amphiphilic invertible polymer (AIP) was used to address the well-recognized problem of poor antigenicity of peptides. We hypothesized that peptides encoding conserved epitopes when conjugated with an AIP will induce strong immune responses and protect against challenge virus. While the conserved epitopes were previously tested by others in mice, we were the first to test a combination of these epitopes in pigs. Pigs vaccinated with the peptide polymer vaccine mounted strong antibody responses against the epitopes indicating that the delivery system was effective. However, protection against replication of the challenge virus was delayed. In summary, the methods developed and tested in this body of work significantly contribute to the area of emergency response management in infectious disease outbreaks. / United States Department of Agriculture, National Institute of Food and Agriculture (USDA-NIFA) / North Dakota State Agricultural Products Utilization Committee (ND APUC) / North Dakota State Board of Agricultural Research (ND SABRE)

Many people may have become increasingly concerned about the risks associated with vaccines. At the same time, there is a lack of qualitative research on the impact of various vaccinations schedules on individuals' physio-psychological health. In addition, "mandatory" versus "nonmandatory, but recommended" vaccines are still under debate in some Western countries. The purpose of this ethnographic study was to provide an in-depth understanding of the beliefs, experiences, and perceptions of adolescents, parents, and health care providers regarding different vaccination schedules. The health belief model was used as the theoretical framework. The sample consisted of adolescents and parents from different vaccination backgrounds, as well as of healthcare providers who were involved with vaccination schedules (N=72). Purposeful sampling strategy was applied and individual interviews were conducted. All interviews were recorded and transcribed verbatim, and the obtained data were analyzed thematically. According to the results of the study, participants' perceptions on vaccination were generally positive, and a mandatory vaccination schedule was mostly recommended. Adolescents who received mandatory vaccination reported that this scheme was appropriate against several diseases. Further, health care members indicated that vaccination side effects were mainly emotional, and they suggested that public health agencies should disseminate more scientifically-sound information on the benefits and risks of vaccination. The findings of this study may be used as the basis for the formulation of an effective public health policy to adopt a nationally-and internationally-accepted vaccination schedule.