A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the degree of Master of Science in Epidemiology in the field of Epidemiology & Biostatistics November 2016 / Background The vaccination coverage estimates reported for South Africa by WHO are below the 90% target indicating that many children in South Africa remain unvaccinated. Data on proportion of children with delayed vaccination and factors leading to missed and delayed vaccination are limited in this setting. The aim of this study was to describe the vaccination coverage and assess factors associated with missed and delayed vaccination in South Africa. Methods and material A secondary data analysis which used data from two Healthcare Utilisation Surveys was conducted in Soweto, Johannesburg in 2012 and in Edendale, Pietermaritzburg in 2013. The analysis was restricted to children aged less than 5 years who had immunisation cards/ vaccine histories. Vaccination coverage and proportion of children with delayed vaccination were calculated for each vaccine dose recommended during the first year of life as described in the South Africa Expanded Programme on Immunisation. Pearson’s Chi square test and Fisher’s exact test were used to compare vaccination coverage across sites. Factors association with delayed and missed third doses of the Diphtheria Tetanus Pertussis vaccine (DTP3) were assessed using univariate and multivariate logistic regression models. Results Vaccination coverage was high (above 90%) for most vaccines except for the third dose of the pneumococcal conjugated vaccine (PCV3) and the second dose of rotavirus vaccine, which had coverage of 80.3% and 85.4% respectively. In Edendale, the coverage for all vaccines appeared to be lower than in Soweto. Vaccination coverage in Soweto ranged from 83.4% to 99.4% and 66.9% to 95.9% in Edendale. In Soweto, DTP3 coverage decreased significantly from 2008 to 2012 (p<0.0001). The highest DTP3 coverage in Soweto was in children aged 48-59 months (98.4%, p<0.0001). In Edendale there was no significant trend observed in coverage by age group or year. A higher proportion of delayed DTP3 vaccination was observed among children aged 12-23 months in Soweto (36.7%, p=0.007) and among children aged 36-47 months in Edendale (42.3%, p<0.0001). Delays were more common in children born in 2010 (47.2%, p<0.0001). Factors associated with missed vaccination after controlling for other factors were child’s age below 12 months (OR 2.7, 95% CI 1.2-5.9) compared to children age 12-23 months, two or more children aged less than 5 years of age in a household (OR 2.5, 95% CI 1.4-4.5) compared to one child and household monthly income less than R500 (OR 2.9, 95% CI 1.03-8.0) compared to a monthly income of more than R2000. Factors associated with delayed vaccination after adjusting for other factors included being born in 2010 (OR 2.9, 95% CI 1.3-6.3) or 2011 (OR 2.7, 95% CI 1.3-5.8) compared to being born in 2008 and a low level of education for the primary caregiver, where caregivers who completed secondary education was associated with lower odds of delayed vaccination (OR 0.5, 95% CI 0.3-0.9) compared with caregivers who had only primary education. Discussion Although most vaccines had high coverage, there were substantial delays in receipt of some vaccines. This difference suggests that both coverage and timely vaccination may be useful as an indicator for immunisation programme performance. Efforts to increase vaccination coverage and timeliness should take into account caregiver’s level of education, number of children aged less 5 years in a household, household income and child’s age to improve child health. Vulnerable groups identified in this study should be targeted with improved vaccination services to enhance uptake and timeliness of vaccination. / MT2017

Thesis (MPH) -- University of Limpopo, 2011. / Background and aim: The development of vaccines is considered one of the greatest achievements of biomedical science and public health, because it has led to the reduction of the global burden of infectious diseases. However, vaccination has become a victim of its own success, since most parents have not been exposed to epidemics of vaccine-preventable diseases, and now some fear the vaccines more than the diseases that they prevent. Globally, there is a growing number of parents who use the internet to seek advice on vaccination, and unfortunately some of this advice is anti¬vaccination (A V). Some studies have analyzed vaccine criticism on the internet, but none have focused on South Aftica (SA). The purpose of this study was to identify the characteristics of the anti¬vaccination lobby on SA internet sites including blogs using search terms that were specifically aimed at increasing the retrieval of A V sites. Methods: A structured internet search was conducted on SA web pages using Google, Yahoo, and MSN search engines, for keywords "don't vaccinate", "vaccination is harmful", "should not vaccinate", " not vaccinating", "vaccination causes harm", "against vaccines", etc. The words "immunization" and "immunisation" were also substituted for the word "vaccination" in these searches. These A V sites were then extracted for analysis of content and authors. Results: The overall coverage of SA A V websites was 30.2% (19/63), with Google identifying the most A V sites (59.3% [16/27]), compared to 33.3% (9/27) for Yahoo and 7.4% (2/27) for MSN. Of these A V sites 42.1 % (8/19) were identified to be blogging sites. The A V advocates included 36% (5/14) mothers / parents, 26% (4/14) business people, and 21% (3/14) journalists. The main concerns identified included vaccine safety and efficacy, ethical concerns, and claimed financial profit motives. There were 32% (6/19) of the authors who referenced or posted articles written by other A V lobbyists from the USA. Conclusion: The A V advocates on SA internet are individuals who are independently lobbying against child vaccination and not a cohesive A VL group. The concerns they raised are similar to those raised by A VL from the USA. The SA population is therefore exposed to influences on the internet both ftom local and international views. The internet blogs and forums are an important platform for sharing A V views in an informal manner.

Public perceptions of vaccination have changed greatly since George Bernard Shaw unleashed his diatribe against the practice. Today it is recognised that, far from spreading disease, vaccination is one of the cheapest and most effective public health interventions. Immunization against infectious diseases has drastically reduced mortality and morbidity, particularly among children, and has diminished the disease burden caused by poliomyelitis, rubella, measles, tetanus, diphtheria, and whooping cough, amongst others. By one estimation, paediatric immunization worldwide prevents approximately 3 million child deaths each year, and saves 750 000 more from disability.

In 1999-2000, the Texas A&M University Ranch to Rail Program evaluated 1311 steers in two feedlots. The first was the Swisher County Cattle Company in Tulia, Texas and the other was Hondo Creek Cattle Company in Edroy, Texas. Data were collected on several traits, but from this project emphasis was placed on preweaning (PreVac) and postweaning (PosVac) vaccinations and the potential influence on growth and carcass traits. Independent variables used in the analyses were location of the feedyard (LOC), PreVac, PosVac, PreVac*PosVac, LOC* PreVac, LOC*PosVac, LOC*PreVac*PosVac, Ranch of origin (RANCH) nested within LOC*PreVac*PosVac, number of days from weaning to shipping to the feedyard (WNTSHP), and days on feed (DOF). Dependent variables evaluated for live cattle traits were average daily gain (ADG), medicine costs (MED), and initial value upon arriving at the feedyard. Dependent variables evaluated for carcass traits were hot carcass weight (HCW), ribeye area (REA), yield grade (YG), and gross value (GROSS). RANCH (P < 0.0001) and DOF (P < 0.0001) had large impacts on ADG. PreVac*PosVac (P = 0.0209), LOC*PosVac (P = 0.0028), RANCH (P < 0.0001), and DOF (P = 0.0003) all had significant effects on MED. PreVac (P < 0.0001), PreVac*PosVac (P < 0.0001), LOC (P < 0.0001), LOC* PreVac*PosVac (P = 0.0002), RANCH (P < 0.0001), and DOF (P < 0.0001) all had significant impact on Initial value. RANCH (P < 0.0001) was the only significant influence on HCW. LOC (P = 0.0587), LOC*PosVac (P = 0.0525), LOC*PreVac*PosVac (P = 0.0594) all had slightly significant effect on HCW. LOC (P < 0.0001) and RANCH (P < 0.0001) had a significant effect on REA while DOF (P = 0.0535) had slight significant effect. LOC (P = 0.0032), RANCH (P < 0.0001), and DOF (P < 0.0001) had significant impact on YG. RANCH (P < 0.0001) had a significant effect and DOF (P = 0.0552) had slight significance on GROSS. The data indicate that RANCH and to a lesser extent DOF have the most influence on both feedyard and carcass traits.

Background Influenza causes annual, worldwide epidemics of respiratory disease that affects all segments of the population. Mass vaccination of healthy children, who are playing an important role in the transmission of influenza, is promoted to be a complementary approach in prevention and control of influenza. However, lack of published systemic review evidencing the indirect protection of vaccinating healthy children makes the implementation under uncertainty. Method A systemic review was conducted by computerized bibliographic searches in PubMed and the Cochrane Library identifying the published studies on the effectiveness and cost-effectiveness of vaccinating healthy children to control influenza epidemics by reducing transmission in the community. Any study design with vaccinating healthy children as the intervention versus control group with no influenza vaccine was included. Only outcomes measured on the contacts of children, either the community or household members were considered. Result Twenty-two articles were selected to be reviewed in this project, in which 17 of them covered the public health benefit of vaccinating healthy children to protect others in the community against influenza, and five of them were economic studies. Overall the result suggested that vaccinating health children produces a public health benefit in protecting others in the community against influenza and that it is a cost-effective measure. Discussion Targeting vaccines to healthy children should be promoted for optimal vaccine allocation, maximizing the vaccination effectiveness. Community planning on vaccine delivery infrastructure as well as educational and communicational strategies is necessary to improve influenza vaccine coverage. Further well-designed studies such as RCT with larger sample sizes, as well as studies in Hong Kong or other sub-tropical regions should be carried out and included. Moreover, large and population-based studies should be conducted to examine the overall impact of universal childhood influenza immunization. / published_or_final_version / Public Health / Master / Master of Public Health

Diss. (sammanfattning) Uppsala : Univ., 2004. / Härtill 4 uppsatser.

Thesis (M.A.)--University of Wisconsin--Madison, 1966. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Th.--Méd.--Nancy 1, 1984. N°: 259.

Reproduction de : Thèse d'exercice : Médecine : Nancy 1 : 2007. / Titre provenant de l'écran-titre.

No description available.