Thesis (M.Med.Sc.)--University of Hong Kong, 2002. / Includes bibliographical references. Also available in print.

Title from title page of PDF (University of Missouri--St. Louis, viewed Mar. 2, 2010). Includes bibliographical references.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 5 uppsatser.

Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2016-03-22T18:32:18Z No. of bitstreams: 1 Milena Soares dos Santos Efeito....docx: 5951904 bytes, checksum: d28e49e9a6c37cb463504bb5cf122c6f (MD5) / Approved for entry into archive by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2016-03-22T18:32:30Z (GMT) No. of bitstreams: 1 Milena Soares dos Santos Efeito....docx: 5951904 bytes, checksum: d28e49e9a6c37cb463504bb5cf122c6f (MD5) / Made available in DSpace on 2016-03-22T18:32:30Z (GMT). No. of bitstreams: 1 Milena Soares dos Santos Efeito....docx: 5951904 bytes, checksum: d28e49e9a6c37cb463504bb5cf122c6f (MD5) Previous issue date: 2015 / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, Brasil / Streptococcus pneumoniae é uma bactéria patogênica que afeta crianças e idosos em todo o mundo, sendo responsável por elevada morbidade e mortalidade, especialmente nos países em desenvolvimento onde o acesso às vacinas pneumocócicas conjugadas (PCVs) é limitado. A colonização da nasofaringe precede o desenvolvimento de infecções e as crianças são o principal reservatório deste patógeno na comunidade. As vacinas pneumocócicas conjugadas reduzem a taxa de colonização e de doenças causadas por sorotipos vacinais, entretanto, pouco se sabe sobre seu efeito em eventos na substituição de sorotipos. Os objetivos deste estudo foram determinar o efeito da vacina pneumocócica conjugada 10-valente (PCV10) na colonização nasofaríngea por pneumococos em crianças menores que um ano, saudáveis e que apresentaram doença crônica ou desordem imunológica nos períodos pré- e pós esquema vacinal primário entre maio de 2011 a janeiro de 2014 e determinar a influência desta vacina na distribuição de sorotipos, da susceptibilidade antimicrobiana e do perfil genotípico dos pneumococos. Foram investigadas 168 crianças, sendo 63 do grupo de portadores de doenças clínicas (Grupo I) e 105 do grupo de crianças sadias (Grupo II). O isolamento, a identificação e a avaliação da resistência antimicrobiana do pneumococo foram realizados através de técnicas microbiológicas convencionais. A determinação dos sorotipos capsulares foi realizada através das técnicas de reação de polimerase em cadeia multiplex e reação de Quellung. A taxa de colonização pneumocócica total foi de 24%, sendo 17% (11/63) e 28% (29/105) para os grupos I e II, respectivamente. Convívio com crianças menores que 6 anos no mesmo domicílio mostrou associação com colonização para o grupo I [OR= 8,36 (IC95%= 1,69-44,70); p=0.004 enquanto que renda foi associada a risco para crianças do grupo II [(OR=3,22; IC95%= 1,22-8,64; p=0,01]. Os sorogrupos/tipos identificados com maior frequência foram: 23F (10%), 19F e 15B/15C (7,5%) e cepas não tipáveis (15%), Após a 3 ª dose da vacina houve uma redução de 7% para 5% na taxa de colonização por sorotipos vacinais e um aumento de três vezes na probabilidade de colonização por sorotipos não vacinais (7% para 21%). Identificamos 17% de não susceptibilidade à penicilina. Os sorotipos PCV10 associados com um ST foram os sorotipos 19F (ST177) e 23F (ST338) e os não associados a PCV10 foram os seguintes: 11A/11D (ST62 e ST408), 15A/15F (ST73), 15B/15C (ST766), 23A (ST42) e 23B (ST727). Os resultados demonstram que três doses da PCV10 reduzem ou estabilizam a colonização por sorotipos vacinais, a despeito da colonização pelos sorogrupos/tipos vacinais 6A/6B, 14 e 23F e destaca-se a colonização por sorotipos não vacinais (6C<7C<13<23A<23B<15A/15F<15B/15C<11A/11D) e cepas não tipáveis, independente do grupo de crianças avaliadas. Embora não tenha sido avaliado o efeito da PCV10 após a 4ª dose da vacina neste estudo, ressaltamos a importância da manutenção da dose de reforço no calendário vacinal do programa nacional de imunizações para que a proteção contra os sorotipos oferecida pela vacina seja alcançada. Estudos epidemiológicos devem continuar para monitorar a taxa de colonização de pneumococos circulantes no período pós-vacinal, bem como as taxas de não susceptibilidade aos antimicrobianos que são essenciais para o direcionamento das estratégias de saúde pública no manejo clínico e prevenção das doenças pneumocócicas. / Streptococcus pneumoniae is a pathogenic bacterium that affects children and elderly throughout the world, accounting for high morbidity and mortality, especially in developing countries where acess to pneumococcal conjugate vaccines (PCVs) is limited. Nasopharyngeal colonization precedes the development of infections and children are the main reservoir of this pathogen in the community. The pneumococcal conjugate vaccine has been effective in reducing colonization and disease by vaccine serotypes, however, little is known about its effect on the overall rate of colonization due to serotypes replacement events. The study aims to evaluate the effect of pneumococcal conjugate vaccine on nasopharyngeal carriage in children younger than one years old, healthy, suffering from crhonic diseases or immune disorders during vaccine primary immunization with PCV-10 between may 2011 and jaanuary 2014 and the influence of this vaccine in the distribution of serotypes, antimicrobial susceptibility and genotypic profile of pneumococcus. A total of 168 children were enrolled, 63 with chronic diseases (Group I) and 105 of the group of healthy children (Group II). The isolation, identification and evaluation of antimicrobial resistance of pneumococci were made using conventional microbiological techniques. The determination of capsular serotypes was performed using the multiplex-PCR and/or Quellung reaction. Overal, the pneumococcal colonization rate was 24%, being 17% (11/63) and 28% (29/105) to group I and II, respectively. Living with children aged up to six 6 years in the same household was associated with colonization in group I[OR= 8,36 (CI95%= 1,69-44,70); p=0.004] and income was associated with risk for children in group II [(OR=3,22; IC95%= 1,22-8,64; p=0,01]. The most frequently serotypes identified were: 23F (10%), 15B/15C (7,5%) and nontypeable strains (15%). A total of 28% (11/40) of serotypes identified in both groups are represented in PCV10. After the 3rd dose of vaccine was reduced from 7% to 5% in vaccine serotypes colonization rate and a three-fold increase in the probability of colonization by serotypes not represented in the PCV-10 (7% to 21%). Penicillin nonsusceptibility was identified in 17% of the isolates. PCV10 serotypes associated with a ST serotypes were 19F (ST177) and 23F (ST338) and not associated with PCV10 were 11A/11D (ST62 and ST408), 15A/15F (ST73), 15B/15C (ST766), 23A (ST42) and 23B (ST727). The results demonstrate that three doses of PCV10 stabilizes or reduces colonization by the vaccine serotypes, regardless of colonization by vaccines types 6A/6B, 14 and 23F and highlight the rates of colonization by non vaccine serotypes (6C<7C<13<23A<23B<15A/15F<15B/15C<11A/11D) and nontypeable pneumococcal, independent of the study group. Although this study was not evaluated the effect of PCV10 after the 4th dose of the vaccine, we emphasize the importance of booster dose of maintenance in the immunization schedule of the national immunization program for the protection offered by the vaccine serotypes is achieved. Epidemiological studies should continue to monitor the rate of colonization of pneumococci circulating in the post-vaccine period and antimicrobial non-susceptibility rates that are essential for the targeting of public health strategies in the clinical management and prevention of pneumococcal diseases.

Masters of Science / Invasive pneumococcal disease (IPD), which includes potentially fatal conditions such as meningitis, septicaemia and pneumonia poses a threat in children aged <5 years, pneumonia being the leading cause of child mortality worldwide. Even though capsular polysaccharides are the main antigens involved in the immunity to encapsulated bacteria, it was found that in children in that age group, the immune system was unresponsive. Conjugate vaccines however induce immunologic memory and provide long-term protective immunity. Therefore the aim of this project was to develop novel conjugation strategies towards a pneumococcal conjugate vaccines and focuses mainly on the serotypes that are a burden to the African continent. The chemistry involved in developing a conjugate vaccine is of importance beacuse while some polysaccharides contain chemical grouping which can be conveniently utilized for conjugation, many medically important ones require derivatization before they can be coupled to protein. Derivatization of which can be achieved through various strategies, important to note is through hypervalent iodine oxidants. Two hypervalent iodine reagents, O-Methyl substituted-1-hydroxy-1,2-benziodoxol-3(1H)-one 1-oxide (Me-IBX)and modified 1-hydroxy-1,2-benziodoxol-3(1H)-one 1-oxide (mIBX)were successfully synthesized in preparation for the use in polysaccharide, polyribitol phosphate, (PRP) oxidation. The polysaccharide to be oxidised was first size reduced by microfluidisation to allow maximum oxidation. However, the extent to which oxidisation was achieved was not enough to conjugate the polysaccharide to the protein of preference, Bovine Serum Albumin, (BSA).

This thesis aimed to elucidate the demographic characteristics associated with elevated or reduced rates of pneumococcal conjugate 13 (PCV13) vaccination. A retrospective cohort study was performed using the Truven Health MarketScan® Database. Three cohorts were created corresponding to populations for which the CDC recommends PCV13 vaccination. Cohort 1: children < 36 months of age. Cohort 2: adults 19-64 years of age with high infection risk. Cohort 3: adults > 65 years of age. Odds of having a PCV13 claim were calculated for each cohort. For Cohort 1, 78% out of a total of 353,214 subjects had a sufficient number of PCV13 doses to meet CDC recommendations. For Cohort 2, 3.7% out of a total of 673,157 subjects had a PCV13 claim. For Cohort 3, 18% of 1,262,531 subjects had a PCV13 claim. Odds of vaccination were generally lower in younger subjects, those with fewer outpatient claims, and those with residence in the Northeast and South regions. In Cohort 2, odds were reduced in subjects with generalized malignancy. Gender and urban residence were poor predictors of vaccination status. By understanding the demographic factors associated with lower rates of vaccination, clinicians may more effectively direct their efforts to increase pneumococcal vaccination coverage.

No description available.

A dissertation submitted to the Faculty of Medicine, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Medicine. / The emergence of strains of S. pneumoniae resistant to penicillin and to other antibiotics, and the spread of that resistance over the world, have become major concerns and increase the need for epidemiological surveillance. The following typing methods have been used to detect strain variability in pneumococci: Serotyping, antibiotic susceptibility profiles, multilocus enzyme electrophoresis (MLEE), penicillin-binding protein (PBP) profiles, pulse-field gel electrophoresis (pFGE), and ribotyping. Serotyping, antibiograms, and MLEE only detect phenotypic variability. PBP gene profiles, PFGE, and ribotyping detect genotypic differences but these techniques are labour intensive and time consuming. Random amplified polymorphic DNA (RAPD) is a new technique that bas proved useful for typing bacteria, fungi, and parasites, but has not been. studied using pneumococci. Unlike conventional polymerase chain reaction (peR), RAPD utilizes single, short primers, usually 10 oligonucleotides in length. As the primer is short and low astringency annealing temperatures are used, there will be many complimentary sites scattered randomly throughout a bacterium's genome, When such sites occur a few hundred base pairs away from each other and on opposite DNA strands, the enclosed region can be amplified by peR This results in numerous discrete target fragments which can be separated by agarose-gel electrophoresis and ethidium bromide staining. RAPD requires no sequence information and it scans the whole genome rather than relying on hypervariability within one specific gene. The aims of this study were: to determine strain variability using RAPD, to determine the reproducibility ofRAPD, and to demonstrate intercontinental spread of a multiresistant pneumococcal strain. The following strains were evaluated: a) 10 strains from a day-care centre (DCC), the index case being a 3 year old girl 'with otitis media. An aunt from Spain had recently been staying with the family. The other strains were isolated from class mates and siblings of the index case.; b) 18 clinical isolates from Seoul, Korea; and c) 11 epidemiologically unrelated isolates from South Africa, including the reference strain, R6. Two DNA extraction methods were used. The first involving lysis with sodmm-dodecyl-sulphaze and proteinase K. Proteins were removed with phenol-chloroform, and the DNA precipitated with ethanol. The second method involved incubating the cells at 95 0C for 15 microlitres, followed by centrifugation. 2 microlitres of the supernatant was then used for each PCR reaction, Three primers were evaluated. After 01uimisation of the RAPDreaction for pneumococci, the final peR mixtures per 50 ul was: primer (4 plY1), template (0.5 ng), nuc1eotides (300 pMeach), magnesium (4 mM~, and Taq polymerase (2 U). 35 cycles were used with an annealing temperature of 35'C. Both DNA extraction methods: gave reproducible results but were not comparable to each other. All 10 strains from the DCC gave the same banding pattern as the Spanish done for all 3 primers. 7 of the Korean strains gave the same banding pattern as the Spanish clone using the first two primers, however one strain showed an additional band using the third primer. Of the remaining 22 strains, 21 different banding patterns were obtained. This study has shown that RAPD is a simple and rapid technique that can distinguish strain variation among pneumococci. The reproducibility is excellent within the same laboratory. Finally using RAPD. this study identified a Spanish multiresistant 23F clone in South Africa and Korea. / Andrew Chakane 2018

Background: An estimated 50,000 adults in the United States (U.S.) die each year from one of 10 vaccine preventable diseases. For those who survive vaccine preventable infections, health care costs and loss of income become more significant. While children in the U.S. aged 0-2 exhibit vaccine prevalence rates of almost 90%, some adult vaccine prevalence rates in the U.S. population are reported to be nearly 30-40% less than the goals set forth by Healthy People 2010. The purpose of this study was to examine the associations between socio-demographic characteristics of U.S. adults and adult vaccination prevalence for pneumococcal, hepatitis A, hepatitis B, tetanus, and pertussis. Methods: Data from the 2008 National Health Interview Survey were assessed examining various health indicators and characteristics of non-institutionalized adults and children. The sample was restricted to adults ≥18 years of age. Odds ratios were calculated and multivariate logistic regression was also conducted. P-values of Results: There were 21781 total observations; 19.3% received the pneumococcal vaccine, 9.4% received the hepatitis A vaccine, 27.2% received the hepatitis B vaccine, 55.1% received the tetanus vaccine, and 15.2% received the pertussis vaccine. Of the socio-demographic characteristics examined, age, health insurance, marital status, and education were significant for either all five or at least four of the vaccines included in this study. As one might expect those who reported health insurance and those who had a higher level of education usually had a higher likelihood of vaccine receipt as compared to those without health insurance and those with less than a high school education. Age associations varied due to age-related recommendations for certain vaccines such as pneumococcal (recommended for adults ≥65). Compared to the married population (referent), marital status results varied, but for reasons unclear. Whites, the referent group, were the most likely to be vaccinated as compared to Blacks, Hispanics/Latinos, and Asians. Hispanics/Latinos typically had the lowest likelihood of vaccination in this examination. Conclusions: This study further explores the impact of socio-demographic disparities on vaccination status and adds new information to the literature regarding adult vaccination rates for preventable diseases. While research exists related to strengthening interventions such as patient reminder systems, those who do not see the same health care providers on a regular basis remain at risk for lower vaccination prevalence. It is important to better understand the role of social determinants of health, specifically in terms of vaccinations. Future research is needed to further characterize the association of socio-demographic factors with receipt of optional vaccines in adults.