Clinical Epidemiologyhttp://hdl.handle.net/2263/25002024-03-28T15:04:31Z2024-03-28T15:04:31ZEffectiveness of pneumococcal vaccine in preventing hospital admissions for pneumonia among the elderlyhttp://hdl.handle.net/2263/767762023-09-07T09:48:41Z2019-01-01T00:00:00ZEffectiveness of pneumococcal vaccine in preventing hospital admissions for pneumonia among the elderly
Introduction
Hospitalisations and prolonged hospital stays impose great economic burden especially at the present time when resources are limited. Community-acquired pneumonia (CAP) is a common and costly illness associated with considerable morbidity and mortality. Other than children, the elderly are the most vulnerable to CAP due to reduced immunity and comorbid chronic conditions. Streptococcus pneumoniae (S. pneumoniae) has been identified as the most common culprit encountered in cases of CAP with the incidence of CAP peaking during the annual influenza season. There is a known synergistic pathogenesis between the influenza virus and S. pneumoniae. Vaccination against invasive pneumococcal disease (IPD) is established in children. However, the burden of pneumonia has remained high in the elderly. This study sought to explore primarily the effectiveness of pneumococcal vaccination, as administered in a South African Medical scheme population, in the elderly who are aged 65 years and older; and secondly to explore the effectiveness of influenza vaccination in the same age group in preventing hospital admissions due to pneumonia (all causes).
Methods
The study population consisted of 34 068 beneficiaries of Medihelp medical aid scheme, and the outcome measures were investigated for years 2017/2018. The researcher has conducted a case-control study using cross-sectional secondary data with 1:1 matching. The sample size consisted of 800 pairs of case and control for primary and secondary exposures (pneumococcal vaccine and influenza vaccine, respectively). ICD-10 (International classification of diseases .10th revision) coding was used to identify study cases based on hospital admission claims and was matched for covariates age, sex and important comorbidities: ischaemic heart disease (IHD), chronic obstructive pulmonary disease (COPD), asthma and diabetes mellitus (DM). For the primary outcome, we adjusted for the use of influenza vaccine and for the secondary outcome, we adjusted for the use of pneumococcal vaccine. McNemar’s odds ratio (OR) and its 95% confidence interval (CI) was used to measure the association between vaccination and hospitalisation for CAP. Sensitivity analyses by means of propensity score matching (PSM) were also performed to estimate the OR. In addition, subgroup analyses were performed by estimating the odds ratios in participants who have used 23-valent pneumococcal polysaccharide vaccine (PPSV-23) and 13-valent pneumococcal conjugate vaccine (PCV-13) respectively for the primary exposure by PSM.
Results
All participants had claimed only one type of pneumococcal vaccine in this study. Vaccine uptake for pneumococcal vaccine and influenza vaccine in the study population were 0.9% and 16.6% respectively. For the primary exposure, 15 (1.9%) cases were exposed to pneumococcal vaccine compared to nine (1.1%) in controls with an OR of 1.67 (95% confidence interval (CI), 0.683 - 4.319) (P= 0.308). Propensity score matching revealed similar estimates, although closer to the null value, with OR of 1.05 (95% CI, 0.991 - 1.121) (P= 0.095). For the secondary exposure, 140 (17.5%) cases were exposed to influenza vaccination compared to 152 (19.0%) controls with an OR of 0.90 (95% CI, 0.683 - 1.178) with a (P= 0.460). Using PSM the OR was 0.99 (95% CI, 0.983 - 0.994) (P<0.001).
Conclusions
In order to enhance the vaccine effectiveness (VE) of pneumococcal vaccine, it is recommended that sequential vaccination with a dose of PCV-13 to be followed by a dose of PPSV-23 one year later in all adults 65 years and older. Once off vaccination with either type of pneumococcal vaccine did not confer a protective benefit in this study. This recommendation is based on guidelines in use for South Africa and other international agencies. Compliance with the guidelines vaccination schedule was found not to be the practice in our study population. For the secondary exposure, our findings reaffirm the significance of seasonal influenza vaccination for the study age cohort. We recommend that programmes to significantly enhance both pneumococcal and influenza vaccine uptake be earnestly addressed in order to address severe uptake deficiencies observed in this study. Both vaccines should be given concurrently in order to enhance compliance and to further reduce the burden of CAP for the study age cohort.
Dissertation (MSc (Clinical Epidemiology)--University of Pretoria, 2019.
2019-01-01T00:00:00ZThe prevalence of intentional and unintentional injuries in selected Johannesburg housing settlementsMendes, J.F.Mathee, A.Naicker, N.Becker, Piet J.Naidoo, S.http://hdl.handle.net/2263/628282022-04-08T22:47:39Z2011-11-01T00:00:00ZThe prevalence of intentional and unintentional injuries in selected Johannesburg housing settlements
Mendes, J.F.; Mathee, A.; Naicker, N.; Becker, Piet J.; Naidoo, S.
Intentional and unintentional injuries were reported to be the
second leading cause of Disability Adjusted Life Years in South
Africa in 2000. We present household experiences of such injuries
in 5 impoverished housing settlements in Johannesburg, Gauteng
Province. Data for this study were extracted from the database of
the Health, Environment and Development (HEAD) project. The
incidence of reported intentional injuries was determined to be
double that of unintentional injuries. Households in the Hospital
Hill and Riverlea settlements reported the highest prevalence of
stabbing and gunshot incidents. We concluded that impoverished
South African neighbourhoods bear a high burden of intentional
injury; surveillance mechanisms are required to inform prevention
strategies at an individual, a community and a societal level.
2011-11-01T00:00:00ZFischer dinuclear and mononuclear bis-carbene complexes of thiophene and thiophene derivativesLotz, SimonVan Jaarsveld, Nina AllettaLiles, David C.Crause, ChantelleGörls, HelmarTerblans, Yvette M.http://hdl.handle.net/2263/585692022-04-08T22:46:27Z2012-01-01T00:00:00ZFischer dinuclear and mononuclear bis-carbene complexes of thiophene and thiophene derivatives
Lotz, Simon; Van Jaarsveld, Nina Alletta; Liles, David C.; Crause, Chantelle; Görls, Helmar; Terblans, Yvette M.
The reaction of dilithiated thiophene and
thiophene derivatives with group 6 transition metal carbonyl
precursors and subsequent alkylation afforded linearly
arranged Fischer 2,5-bis-carbene and the rare unsymmetrical
2,3-bis-carbene chelated complexes. The latter requires a
second lithiation to occur at an adjacent, less reactive site on the thiophene ring. The control of reactivity sites was investigated
and achieved by either blocking more reactive positions with substituents or activating less reactive positions by lithium−halogen
exchange reactions. A series of Fischer bis-carbene chelates were synthesized by manipulating the above variables. Structural
features of Fischer mono-carbene, mononuclear bis-carbene, and bis-carbene chelated complexes were studied by IR, NMR, and
single-crystal X-ray diffraction
2012-01-01T00:00:00ZEffect of metformin therapy and dietary supplements on semen parameters in hyperinsulinaemic malesBosman, E.Esterhuizen, A.D.Rodrigues, Frederico AntonioBecker, Piet J.Hoffmann, W.A.http://hdl.handle.net/2263/528232022-04-08T22:45:23Z2015-11-01T00:00:00ZEffect of metformin therapy and dietary supplements on semen parameters in hyperinsulinaemic males
Bosman, E.; Esterhuizen, A.D.; Rodrigues, Frederico Antonio; Becker, Piet J.; Hoffmann, W.A.
Previous reports indicated that hyperinsulinaemic men may exhibit a higher
percentage of poorly compacted DNA in their spermatozoa and less success in
an IVF programme (Andrologia, 45, 2003, 18; Andrologia, 2014, doi: 10.1111/
and.12227). The aim of this study was to investigate the effect of metformin
(Glucophage ) and antioxidant treatment (StaminoGro ) on the semen parameters
of hyperinsulinaemic men. Nineteen hyperinsulinaemic male patients were
treated for 3 months with metformin alone (Group A), and fifteen patients used
metformin in combination with the nutritional supplement (Group B). Combined
data of the two groups (pre- and post-treatment) differ significantly
regarding sperm morphology (P = 0.0003) and CMA3 (P < 0.0001) values. The
improvement in sperm morphology after treatment was similar for the two
respective groups (P < 0.05). The morphological normal sperm forms increased
from the mean percentage of 3.9 to 5.5% and from 4.2 to 5.5% for Group A
and B respectively. Where a combination of metformin and the supplement
were used (Group B), the combination treatment proved to be superior in
obtaining enhanced chromatin packaging quality although not statistically significant
(P = 0.5929) when compared with the metformin (Group A) group.
The chromatin packaging quality in Group B improved with 10% while the
improvement in Group A was approximately 8.3%. Therefore, infertile hyperinsulinaemic
men can benefit from metformin treatment and should be advised
on the use of nutritional supplements with antioxidant properties.
2015-11-01T00:00:00Z