Support of smoking restriction in public areas among adolescents in Malaysia-the findings from tobacco and e-cigarette survey among adolescents in Malaysia (TECMA)

Adolescents are the future generation, and their support for smoke-free policies might create momentum for future stringent smoke-free initiatives. This study aimed to determine the levels and factors associated with support for smoking in public areas among Malaysian school-going adolescents aged 10-19 years. The data were derived from the Tobacco and E-cigarettes among adolescents in Malaysia (TECMA), which employed the cross-sectional study design and multistage sampling to select the representative samples of school-going adolescents. Data was obtained through self-administered of pre-validated questionnaire. Descriptive study, cross-tabulation and multivariable analysis were used for analysis. Majority of respondents supported smoking restriction in public areas (86.3%, 95 CI 85.4-87.1). The proportion and likelihood of support of smoke-free initiative were higher among respondents with better knowledge of the harmful effects of second-hand smoke (SHS), been taught in school about the health effects of smoking, older age group (16-19 years), female, those students schooling in urban areas, Malay and other Bumiputras from Sabah and Sarawak. However, current smokers and ECV users were less likely to support smoke-free initiatives in public areas. The level of support for smoke-free initiative in public areas was high among youths in Malaysia, and this might offer promising prospects to expand the non-smoking areas to more public areas in the future

Prevalence and factors associated with smoking cessation among elderly in Malaysia- A findings from the population-based study

Introduction: The information of prevalence and associated factor(s) with smoking cessation among the elderly will assist in formulating the suitable policies and reducing the mortality among Malaysian elderly due to smoking-related diseases. This paper aims to describe the prevalence and factor(s) associated with smoking cessation among Malaysian elderly. Methods: We carried out the population-based study using the cross-sectional study design and a sample size of 2,674 respondents obtained via a multistage sampling method. Validated questionnaire and face-to-face interviews approach were the methodologies employed to collect data from the selected respondents. The interview was conducted by trained enumerator using a standardized and validated questionnaire. Descriptive and multiple logistic regression were used in data analysis. Results: The present findings demonstrated that almost 1 out of 10 of Malaysian elderly are current smokers. The prevalence of smoking was significantly higher among men (28.1%) compared to women (2.9%). Multivariable analysis showed that males and other ethnicities were less likely to cease smoking, while those with advancing age were more likely to stop smoking compared to the younger-aged elderly. Based on multivariate analysis, diabetes, hypertension and hypercholesterolemia were not significant factors associated with smoking cessation. Conclusions: The study has shown a low proportion of Malaysian elderly is ex- smoker. Suitable measures and programmes should be formulated and implemented to increase the quit smoking rate among them and subsequently to increase the quality of life by reducing the burden of smoking-related disease among the Malaysian elderly

Construct validity and reliability of Malay language-perception towards smoking questionnaire (BM-PTSQ) among secondary school adolescents

Multitude studies have demonstrated that perception is an integral factor associated with smoking. However, no such tool was available in the Malay language. In this study, we established a Bahasa Malaysia version of PTSQ (BM-PTSQ) and tested the validity and reliability among secondary school adolescents. The English version of PTSQ originally consists of 12 items. It was translated into Bahasa Malaysia and back-translated again into English to check for consistency. After face validity (face-to-face query) was determined among 20 secondary school adolescents, only 10 items were included in the survey. Construct validity was established from 407 school adolescents through random selection in the same locality. More than 60% of the respondents were female, while the majority of them (67.3%) were schooling in rural areas. Then, the reliability of the questionnaire was determined with Cronbach’s alpha. The Exploratory Factor Analysis (EFA) has grouped PTSQ into two components associated with either knowledge or attitude towards smoking. The variance and Cronbach’s alpha for the first and second components were 38.24% and 0.861 (7 items), 21.62% and 0.661 (3 items), respectively. The PTSQ showed good validity and reliability for measuring perception of smoking among secondary school-going adolescents in Malaysia. Hence, this is a viable measurement tool. But, more importantly, this study showed an urgent need to improve smoking education among adolescents in Malaysia

Characterization of sodium channel mutations in the dengue vector mosquitoes Aedes aegypti and Aedes albopictus within the context of ongoing Wolbachia releases in Kuala Lumpur, Malaysia

Specific sodium channel gene mutations confer target site resistance to pyrethroid insecticides in mosquitoes and other insects. In Aedes mosquito species, multiple mutations that contribute to resistance vary in their importance around the world. Here, we characterize voltage sensitive sodium channel (Vssc) mutations in populations of Aedesaegypti from Kuala Lumpur, Malaysia, and look at their persistence in populations affected by ongoing Wolbachia releases (a dengue control measure). We also describe a Vssc mutation in Aedesalbopictus (F1534L) found for the first time in Malaysia. We show that there are three predominant Vssc haplotypes in Aedesaegypti in this region, which all persist with regular backcrossing, thereby maintaining the original genetic composition of the populations. We identify changes in genotype frequency in closed populations of Ae. aegypti maintained for multiple generations in laboratory culture, suggesting different fitness costs associated with the genotypes, some of which may be associated with the sex of the mosquito. Following population replacement of Ae. aegypti by Wolbachia in the target area, however, we find that the Vssc mutations have persisted at pre-release levels. Mosquitoes in two genotype classes demonstrate a type I pyrethroid resistance advantage over wildtype mosquitoes when exposed to 0.25% permethrin. This resistance advantage is even more pronounced with a type II pyrethroid, deltamethrin (0.03%). The results point to the importance of these mutations in pyrethroid resistance in mosquito populations and the need for regular backcrossing with male mosquitoes from the field to maintain similarity of genetic background and population integrity during Wolbachia releases

Establishment of Wolbachia strain wAlbB in Malaysian populations of Aedes aegypti for dengue control

Dengue has enormous health impacts globally. A novel approach to decrease dengue incidence involves the introduction of Wolbachia endosymbionts that block dengue virus transmission into populations of the primary vector mosquito, Aedes aegypti. The wMel Wolbachia strain has previously been trialed in open releases of Ae. aegypti; however, the wAlbB strain has been shown to maintain higher density than wMel at high larval rearing temperatures. Releases of Ae. aegypti mosquitoes carrying wAlbB were carried out in 6 diverse sites in greater Kuala Lumpur, Malaysia, with high endemic dengue transmission. The strain was successfully established and maintained at very high population frequency at some sites or persisted with additional releases following fluctuations at other sites. Based on passive case monitoring, reduced human dengue incidence was observed in the release sites when compared to control sites. The wAlbB strain of Wolbachia provides a promising option as a tool for dengue control, particularly in very hot climates

Spatial distribution and long-term persistence of Wolbachia-infected Aedes aegypti in the Mentari Court, Malaysia

Dengue is endemic in Malaysia, and vector control strategies are vital to reduce dengue transmission. The Wolbachia strain wAlbB carried by both sexes of Ae. aegypti was released in Mentari Court, a high-rise residential site, in October 2017 and stopped after 20 weeks. Wolbachia frequencies are still being monitored at multiple traps across this site, providing an opportunity to examine the spatiotemporal distribution of Wolbachia and mosquito density with respect to year, residential block, and floor, using spatial interpolation in ArcGIS, GLMs, and contingency analyses. In just 12 weeks, Wolbachia-infected mosquitoes were established right across the Mentari Court site with an overall infection frequency of >90%. To date, the Wolbachia frequency of Ae. aegypti has remained high in all areas across the site despite releases finishing four years ago. Nevertheless, the Wolbachia invaded more rapidly in some residential blocks than others, and also showed a relatively higher frequency on the eighth floor. The Ae. aegypti index tended to differ somewhat between residential blocks, whilst the Ae. albopictus index was relatively higher at the top and bottom floors of buildings. In Mentari Court, only a short release period was required to infiltrate Wolbachia completely and stably into the natural population. The results inform future releases in comparable sites in a dengue control programme

Introduction of Aedes aegypti mosquitoes carrying wAlbB Wolbachia sharply decreases dengue incidence in disease hotspots

Partial replacement of resident Aedes aegypti mosquitoes with introduced mosquitoes carrying certain strains of inherited Wolbachia symbionts can result in transmission blocking of dengue and other viruses of public health importance. Wolbachia strain wAlbB is an effective transmission blocker and stable at high temperatures, making it particularly suitable for hot tropical climates. Following trial field releases in Malaysia, releases using wAlbB Ae. aegypti have become operationalized by the Malaysian health authorities. We report here on an average reduction in dengue fever of 62.4% (confidence intervals 50-71%) in 20 releases sites when compared to 76 control sites in high rise residential areas. Importantly the level of dengue reduction increased with Wolbachia frequency, with 75.8% reduction (61-87%) estimated at 100% Wolbachia frequency. These findings indicate large impacts of wAlbB Wolbachia invasions on dengue fever incidence in an operational setting, with incidence expected to further decrease as wider areas are invaded

Dengue disease in Malaysia

Der Klimawandel hat weitreichende Folgen auf die Gesundheit der Menschen. Insbesondere Übertragungskrankheiten wie Dengue bekommen global gesehen eine zunehmende Bedeutung. Über die raumzeitliche Verteilung und das Umwelt-Dengue Risiko ist bisher wenig bekannt. Das Hauptziel dieser Dissertation war es daher, die Ätiologie von Dengue in einem hoch endemischen Gebiet besser zu verstehen. Es wurden räumliche Muster des Krankheitsauftretens untersucht, die anschließend in einer Umwelt-Risiko Analyse mit örtlichen Wetterdaten und Landnutzungsinformationen in Zusammenhang gebracht wurden. Zunächst wurde ein raumzeitlicher Ansatz durchgeführt, um herauszufinden, in wie weit Analysen, die verschiedene Aggregationsebenen miteinander kombinieren, zu neuen Erkenntnissen von raumzeitlichen Mustern von Dengue beitragen können. Anschließend wurde ein auf nicht-lineare zeitliche Einflüsse kontrolliertes, Poisson-generalisiertes additives Regressionsmodell genutzt, um herauszufinden, welchen Einfluss Wetterparameter auf die Verbreitung von Dengue haben. Schließlich wurden Boosted regression trees verwendet, um auf nicht-lineare Zusammenhänge und Interaktionen zwischen einzelnen Landnutzungsfaktoren und Dengue zu kontrollieren und um eine Risikokarte zu erstellen. Die Ergebnisse deuten darauf hin, dass mehr als eine geographische Ebene notwendig ist, um Krankheitscluster zu bestätigen. Minimaltemperatur, Regenmenge, und Windgeschwindigkeit waren mit der Verbreitung von Dengue im Untersuchungsgebiet assoziiert. Räumliche Dengue-Muster konnten durch Siedlungen, Wasser, gemischte Landwirtschaftsflächen, offene Flächen und stillgelegte Grünflächen erklärt werden. Dengue-Risiko ist auf der Ergebniskarte des Studiengebietes ersichtlich. Diese Dissertation liefert sowohl wertvolle Informationen für die Gesundheitspolitik in Malaysia als auch wichtige Herangehensweisen für die Entwicklung von Dengue-Kontrollmechanismen in und über die Untersuchungsregion hinaus.Global changes to our earth system have impacts on human health; specifically vector-borne diseases such as dengue are of epidemiological importance. Dengue is a global disease burden. Little is known about the spatio-temporal distribution and environmental risk association of dengue disease. The main goal of this dissertation was to improve understanding of the etiology of dengue disease in a highly endemic region by focusing on, initially, vulnerability mapping of the disease occurrences and, next, environmental risk assessment between disease clusters and both weather and land use. First, a Spatio-temporal scan statistics approach was used to assess to what extent analyses that combine sub-district and address level data contribute to new insights into spatio-temporal dengue disease patterns to better inform health interventions. Second, a Poisson generalized additive model was used to assess the weather effects on dengue disease accounting for non-linear temporal effects. Third, a Boosted regression trees approach was used to account for nonlinearities and interactions between the land use factors and dengue disease and to generate a risk map. Results suggested that more than one geographical level was needed to confirm the disease clusters. Minimum temperature, rainfall and wind speed, were associated with the dengue cases in the study area. Spatial patterns of dengue cases could be explained by land use types, including human settlements, water bodies, mixed horticulture land, open land and neglected grassland. The predicted risk map depicted dengue risk in the study area. This dissertation provided compelling approaches that are highly valuable for dengue vector control policy advice; applicability is not confined to Malaysia but is transferable to other studies in similar settings

Assessing Weather Effects on Dengue Disease in Malaysia

The number of dengue cases has been increasing on a global level in recent years, and particularly so in Malaysia, yet little is known about the effects of weather for identifying the short-term risk of dengue for the population. The aim of this paper is to estimate the weather effects on dengue disease accounting for non-linear temporal effects in Selangor, Kuala Lumpur and Putrajaya, Malaysia, from 2008 to 2010. We selected the weather parameters with a Poisson generalized additive model, and then assessed the effects of minimum temperature, bi-weekly accumulated rainfall and wind speed on dengue cases using a distributed non-linear lag model while adjusting for trend, day-of-week and week of the year. We found that the relative risk of dengue cases is positively associated with increased minimum temperature at a cumulative percentage change of 11.92% (95% CI: 4.41–32.19), from 25.4 °C to 26.5 °C, with the highest effect delayed by 51 days. Increasing bi-weekly accumulated rainfall had a positively strong effect on dengue cases at a cumulative percentage change of 21.45% (95% CI: 8.96, 51.37), from 215 mm to 302 mm, with the highest effect delayed by 26–28 days. The wind speed is negatively associated with dengue cases. The estimated lagged effects can be adapted in the dengue early warning system to assist in vector control and prevention plan

A critique of ISO 9000

The SISIR-ISO 9000 certification schemes were launched in January 1992. To date, 490 certificates have been issued and the schemes' popularity is still growing. Much of current research has concentrated on the benefits of ISO 9000 certification; little attention has been given to examining the criticisms of these quality assurance standards.BUSINES