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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

The epidemiology and prevention of pertussis in Australia

Torvaldsen, Siranda January 2001 (has links)
Pertussis (whooping cough) remains an important public health problem in Australia. Although mortality and morbidity from pertussis declined dramatically following the introduction of mass vaccination programs in 1953, the level of morbidity remains unacceptably high for a vaccine-preventable disease. Aims and methods The primary aims of this thesis were (i) to ascertain the epidemiology of pertussis in Australia between 1993 and 2000 by analysing and interpreting sources of routinely collected data on pertussis; and (ii) to examine the effectiveness of vaccination against pertussis in a number of ways. Data from three primary national sources (notifications of disease, hospitalisations for pertussis and death certificates) were used to examine the burden from pertussis in Australia over these eight years. Analyses included the age distribution of cases, temporal and geographic trends, comparisons of notification and hospitalisation data, and the impact of differences in the method of diagnosis of notified cases between years and age groups. In addition to analyses at the national level using data from the national databases, further detailed analyses were undertaken at the State level for New South Wales (NSW), the most populous Australian State. Pertussis vaccine coverage was estimated using data from the recently established Australian Childhood Immunisation Register (ACIR); these data were also used to track the transition from whole-cell to acellular pertussis vaccines. The different types of studies used to evaluate vaccine effectiveness were reviewed, and a method suitable for ongoing estimation of vaccine effectiveness in Australia was developed. This was then applied to the NSW data, to determine the effectiveness of pertussis vaccination in this State. Main findings The annual notification rate for pertussis in Australia ranged from 23�59 per 100 000 population over the eight years. Infants had the highest notification and hospitalisation rates in Australia � they accounted for 5percent of notifications, 61percent of hospitalisations and 100percent of deaths. Age-specific notification and hospitalisation rates in children aged less than two years strongly suggested a protective effect of vaccination, with the greatest reduction in rate coinciding with eligibility to receive a second dose of pertussis vaccine at four months of age. Notification rates among 5�9 year olds progressively decreased in successive age cohorts, consistent with an effect of the introduction in 1994 of a pertussis vaccine booster for preschool-aged children. Although adults (persons aged 15 years or more) accounted for half the notifications, they had the lowest notification rate. The highest numbers of pertussis notifications were in 1997, when most jurisdictions experienced an epidemic. Notification and hospitalisation rates varied across the States and Territories and also across smaller geographic regions in NSW. Areas and years with high notification rates tended to also have high hospitalisation rates, suggesting that trends in notifications reflected trends in incidence. The number of infant hospitalisations in NSW between July 1993 and June 1999 exceeded the number of notifications by 32percent, highlighting the extent of under-notification. Overall, and particularly amongst those aged more than 12 months, the majority of cases notified in NSW were based on the results of serological tests. The proportion diagnosed by culture of the organism was greatest in infants; the proportion diagnosed by serological tests increased with age. There was no evidence that the use of serology had increased since 1994 in NSW, hence changes in notification rates after this time are unlikely to be attributable to increased use of serological diagnosis. ACIR records indicated that in December 2000, 92percent of one-year-old children had received three doses of diphtheria-tetanus-pertussis (DTP) vaccine and 90percent of two-year-olds had received four doses. Vaccine coverage varied by jurisdiction. Since 1997, there was an increased use of DTP vaccines containing acellular pertussis components with a corresponding decrease in the use of vaccines containing whole-cell components. In 2000, almost all DTP vaccines administered contained acellular pertussis components. The results of the vaccine effectiveness study showed that pertussis vaccination was highly effective at preventing pertussis in NSW children, as measured by notified cases. Vaccine effectiveness was highest (91percent) in the youngest age group (8�23 months) and lowest (78percent) in the oldest age group (9�13 years). The screening method has not previously been used to estimate pertussis vaccine effectiveness in Australia. Conclusions This thesis demonstrates the value of integrating varied data sources in estimating the disease burden from pertussis. The data presented here show that the disease burden is substantial in all age groups, despite high levels of vaccine coverage in infants and children. This problem of disease control does not appear to be due to lack of vaccine effectiveness, but there is evidence of waning immunity over time. The analyses presented here form a basis for the ongoing monitoring of trends in pertussis epidemiology following the replacement of whole-cell by acellular pertussis vaccines, and will assist consideration of the need for additional booster doses in adolescents and adults.
72

Infection by, and immunity to, Vibrio cholerae /

Attridge, Stephen Richard. January 1979 (has links) (PDF)
Thesis (Ph.D.) - Dept of Microbiology, University of Adelaide, 1980.
73

Evaluation of the application of a thermostable Newcastle disease vaccine by community volunteers in the North West Province

Modise, Cynthia Keamogetse. January 2007 (has links)
Thesis (MSc (Veterinary Tropical Diseases))--University of Pretoria, 2007. / Includes bibliographical references.
74

The potency of BCG vaccines determined on animals

Jespersen, Andreas. January 1971 (has links)
Afhandling--Copenhagen. / Summary in Danish. Bibliography: p. [99]-110.
75

Die Abhängigkeit der Immunitätsdauer von der Anzahl und Tiefe der Erstimpfnarben eigene Untersuchungen an 7759 Münchener Schulkindern bei der Wiederimpfung 1933 auf Anzahl und Tiefe der Erstimpfnarben /

Marr, Rudolf. January 1934 (has links)
Thesis (doctoral)--München, 1934.
76

BCG-Lupus

Cremer, Wolfgang, January 1978 (has links)
Thesis (doctoral)--Universität Hamburg, 1978.
77

Plasmodium falciparum candidate malaria vaccine antigen, MSP1.p42, expression in Nicotiana tabacum

Vine, Benjamin G. January 2001 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 2001. / Includes bibliographical references (leaves 65-75). Also available on microfiche.
78

Die Abhängigkeit der Immunitätsdauer von der Anzahl und Tiefe der Erstimpfnarben eigene Untersuchungen an 7759 Münchener Schulkindern bei der Wiederimpfung 1933 auf Anzahl und Tiefe der Erstimpfnarben /

Marr, Rudolf. January 1934 (has links)
Thesis (doctoral)--München, 1934.
79

Immunogenetic analysis of HLA Class II in premalignant disease of the cervix and correlation with HPV status

Odunsi, Adekunle Omatayo January 1999 (has links)
The human papilloma virus (HPY) infection has a causal association with cervical intraepithelial neoplasia (CIN) and cervical cancer. However, pre-malignant or malignant transformation is not always observed with HPY infection. lILA molecules are important in the regulation of the immune response to foreign antigens. The role of genetic variation at the HLA class II loci (DR and DQ) in CIN was investigated in 176 British Caucasian patients and 420 controls (normal cervical cytology and negative for HPY 16, 18, 31 and 33). HLA DQB 1 *03 typing was performed by a novel polymerase chain reactionrestriction fragment length polymorphism method (A-RFLP). The technique uses PCR to mutate the first base of codon 40 (DQ alleles) from T to G to create an artificial restriction site for an enzyme, MluI, which distinguishes DQB 1 *03 from other alleles and is confirmed by digestion of amplified DNA with Mlul. Further HLA DR-DQ typing was performed by PCR DNA amplification and oligonucleotide probe typing. HPY types (16, 18, 31 & 33) were detected by using type-specific oligonucleotide primers and PCR. The alleles of the DQB 1 *03, DRB 1 *04 and DRB 1 * 11 groups were strongly associated with susceptibility to CIN. Specifically the haplotypes DRB 1 *040 I-DQB 1 *0301 and DRBl*1101-DQB1*0301 were significant and indicated susceptibility. The DQBl*03 locus was more contributory to this association than the DRB 1 loci. A weak protective effect was shown for the haplotype DRB 1 *0 10 I-DQB 1 *0501. Positive correlation was also observed for HPY-positive CIN, suggesting that specific HLA alleles may be important in determining the immune response to HPY antigens and the risk for CIN after HPY infection. Immunoaffinity purification of the susceptibility and protective HLA ~ molecules was performed and the naturally processed peptides were eluted and sequenced by Edman degradation. The data obtained was used for motif prediction of HPY 16 E6, E7, Ll and L2 sequences that may be capable of binding to these HLA molecules. Motif prediction as well as the binding affinity of predicted peptide motifs for HLA D RB 1 *0401 and DRB 1 *0 10 1 was accomplished using the published data' on the naturally bound peptide sequences bound to these HLA molecules. The results revealed significant differences in both the number and binding affinity of the HPV 16 derived peptides to the protective and susceptibility HLA molecules. These results should help in the rational design of vaccines against HPV.
80

Cavitation-enhanced transdermal vaccine delivery by ultrasound

Bhatnagar, Sunali January 2014 (has links)
Currently, the most common route for vaccine delivery is by intramuscular injection with a needle and syringe. Injection has number of disadvantages, such as risk of infection at the i njection site, needle prick injuries, and needle phobia that leads to significant levels of patient non-compliance. Therefore, the focus of this thesis is the development of an alternative ultrasound-assisted transdermal vaccine delivery system. To do so, we target immunological Langerhans cells in the epidermal layer of the skin that efficiently provoke an immune response. The stratum corneum (SC) is a barrier that prevents conventional transdermal vaccine delivery. Methods such as microneedles, iontophoresis and thermal ablation are presented in literature for the permabilisation of this layer. Sonophoresis is the use of ultrasound to transport molecules through a medium. Previous studies have demonstrated that the key underpinning mechanism is inertial cavitation, which leads to permeabilisation of the SC and facilitates transdermal delivery. Most studies to date have pre-exposed the skin to ultrasound prior to delivery of a vaccine in liquid form as a droplet placed on the skin. This approach is not practical for widespread use, but more importantly fails to take advantage of the potential of cavitation-mediated micro streaming to enhance active transport of molecules beyond the permeabilised skin. The focus of the present work is the development of a complete system that enables storage of the vaccine in a readily useable gel form whilst promoting and monitoring cavitation activity to simultaneously permeabilise the skin and enhance transdermal vaccine transport. Through initial in vitro studies, we first demonstrated that inertial cavitation can be exploited to promote the active transport of molecular entities such as vaccine molecules from a gel into a biological medium. A gel vaccine dosage formulation is utilised in order to mimic current clinically approved and established clinical ultrasound coupling gel formulations. By comparing the effects mediated at two ultrasound frequencies (0.256 MHz vs 1 MHz) which preferentially promote cavitational microstreaming or acoustic streaming, ultrasound parameters most conducive to producing high levels of inertial cavitation were identified as 0.256 MHz and peak rarefactional pressures on the order of 1 MPa. Three vaccine loaded gels were then formulated with either micro- or nano-sized cavitation nuclei and assessed for the optimal acoustic and chemical characteristics at the predetermined ultrasound parameters. Nano-sized nuclei were shown to be most effective at lowering the inertial cavitation threshold, as well as instigating the highest and most sustained levels of inertial cavitation as indicated by broadband acoustic emissions at the ultrasound focus, without causing any structural damage to the vaccine molecules themselves. Ex vivo data has shown that nanoscale-nucleated inertial cavitation at the skin surface delivered a model vaccine Ovalbumin (OVA) to depths of 500 μm into porcine skin. Novel nanoparticles produced in-house used to enhance and instigate cavitation at lower pressures penetrated to depths of up to 700 μm, due to their small size and unique ability to self-propel. Delivery profiles were obtained using multi-photon microscopy of skin sections immediately after treatment. Analysis of acoustic emissions from the focus showed substantial correlation between high delivery dose and depth, and significant amounts of inertial cavitation (i.e. broadband acoustic emissions from the focus). In vivo studies showed that the delivery achieved to murine skin was significantly (p<0.05) higher in the nanoparticle-assisted ultrasound transdermal vaccination group than the chemical penetration enhancer (positive control) group, with delivery of doses up to 1 μg /treatment, compared to 400 ng in the positive control group. This dose was sufficient to trigger an antigen-specific immune response. Specific anti-OVA IgG antibody levels in the ultrasound-assisted vaccine delivery group were significantly (p<0.05) higher than in all other control groups, and substantially higher than the current gold standard in transdermal delivery – chemical penetration enhancers. Although a low level antibody response was observed transdermally compared to the subcutaneous injection group (indicative of 100% delivery response), it is believed that optimisation of this system will lead to a viable and non-invasive delivery platform for vaccines that can be used both in a primary care setting, and eventually for self-vaccination at home.

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