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Dengue virus (DENV), Japanese encephalitis virus (JEV), and Zika virus (ZIKV) are mosquito-borne flavivirus of medical importance in tropical countries such as Malaysia. However, much remains unknown regarding their prevalence among the underserved indigenous people (Orang Asli) living in communities in the forest fringe areas of Peninsular Malaysia. Information on the prevalence of diseases is necessary to elevate the effectiveness of disease control and preventive measures. This study aimed to determine the seroprevalence of the three major flaviviruses among the Orang Asli and investigate the association between demographic factors and seropositivities. Sampling activities were conducted in the Orang Asli villages to obtain serum samples and demographic data from consenting volunteers. The presence of DENV, JEV, and ZIKV immunoglobulin G (IgG) antibodies in the sera were examined using commercial enzyme-linked immunosorbent assay kits. A focus reduction neutralization assay was performed to measure virus-specific neutralizing antibodies. A total of 872 serum samples were obtained from the Orang Asli volunteers. Serological assay results revealed that DENV IgG, JEV IgG, and ZIKV IgG seropositivities among the Orang Asli were at 4.9%, 48.4%, and 13.2%, respectively. Neutralizing antibodies (FRNT50 ≥ 1:40) against JEV and ZIKV were found in 86.7% and 100.0%, respectively, out of the samples tested. Positive serology to all three viruses corresponded significantly to the age of the volunteers with increasing seropositivity in older volunteers. Findings from the study suggest that Orang Asli are at significant risk of contracting JEV and ZIKV infections despite the lack of active transmission of the viruses in the country., (© 2019 Wiley Periodicals, Inc.)

Temephos is the World Health Organization (WHO) recommended larvicide and is still being utilized worldwide to control larvae of dengue vectors; Aedes aegypti and Aedes albopictus. The efficacy of a commercial temephos product; Temebate® to exterminate the local populations of Ae. albopictus larvae originated from different land use particularly dengue-risk and dengue-free housing localities as well as agrarian localities including oil palm plantations, rubber estates and paddy fields was assessed to verify its bioefficacy in these localities. Field populations of Ae. albopictus larvae were attained via a larval survey at each study locality. Each Ae. albopictus larval population was subjected to a 24-h larval bioassay using Temebate® at operational dosage of 1 mg/L. Almost all Ae. albopictus larval populations demonstrated mortalities between 7.00% and 100.00% by the end of the first 4 h of Temebate® exposure with the resistance ratios between 0.94 and 8.33. After 24 h of Temebate® exposure, all sixteen Ae. albopictus larval populations exhibited increased mortalities with ten of them showing 100% mortalities. These results confirmed the relevance of Temebate® to be continuously used by the residents of these localities as their control efforts against dengue vectors. Nevertheless, Temebate® application by consumers in dengue-risk localities need to be carefully monitored to prevent further development of temephos resistance among Ae. albopictus populations and substantiated with other vector control approaches., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Dengue is widespread globally, but it is more severe in hyperendemic regions where the virus, its vectors, and its human hosts naturally occur. The problem is particularly acute in cities, where outbreaks affect a large human population living in a wide array of socio-environmental conditions. Controlling outbreaks will rely largely on systematic data collection and analysis approaches to uncover nuances on a city-by-city basis due to the diversity of factors., Objective: The main objective of this study is to consolidate and analyse the dengue case dataset amassed by the e-Dengue web-based information system, developed by the Ministry of Health Malaysia, to improve our epidemiological understanding., Methods: We retrieved data from the e-Dengue system and integrated a total of 18,812 cases from 2012 to 2019 (8 years) with meteorological data, geoinformatics techniques, and socio-environmental observations to identify plausible factors that could have caused dengue outbreaks in Ipoh, a hyperendemic city in Malaysia., Results: The rainfall trend characterised by a linearity of R 2  > 0.99, termed the "wet-dry steps", may be the unifying factor for triggering dengue outbreaks, though it is still a hypothesis that needs further validation. Successful mapping of the dengue "reservoir" contact zones and spill-over diffusion revealed socio-environmental factors that may be controlled through preventive measures. Age is another factor to consider, as the platelet and white blood cell counts in the "below 5" age group are much greater than in other age groups., Conclusions: Our work demonstrates the novelty of the e-Dengue system, which can identify outbreak factors at high resolution when integrated with non-medical fields. Besides dengue, the techniques and insights laid out in this paper are valuable, at large, for advancing control strategies for other mosquito-borne diseases such as malaria, chikungunya, and zika in other hyperendemic cities elsewhere globally., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Dengue fever is a mosquito-borne viral infection of humans caused by a virus of the Flaviviridae family. In Malaysia the annual incidence risk of dengue fever for the period 2000 to 2019 ranged from 30 to 390 cases per 100,000. The aim of this paper was to identify spatial, temporal and spatio-temporal clusters of dengue fever in Peninsular Malaysia for the period 2015 to 2017. Counts of confirmed incident cases of dengue fever for each of the 86 districts of Peninsular Malaysia for the period 1 January 2015 to 31 December 2017 (inclusive) and district-level census data allowed us to calculate the incidence rate of dengue fever, defined as the number of confirmed cases of dengue fever per 100,000 person-years at risk. We applied Kulldorff's cylindrical space-time scan statistic and Takahashi et al.'s prismatic space-time scan statistic to the data. We identified no major differences in the number and location of spatial clusters of dengue incidence for 2015, 2016 and 2017 using Kulldorff's and Takahashi et al.'s method. Spatio-temporal clusters of dengue occurred at several times throughout each year in various high population dense areas. These clusters not only included high population density districts but also their adjacent district neighbours. The temporal clustering of dengue cases during the monsoon season (mid September to late December each year) implies that there is a biologically plausible causal association between rainfall and the incidence of dengue. Identification of locations and time periods when the frequency of dengue is high allows Malaysian public health authorities to be more objective in their decision making around vector control and dengue public awareness campaigns. Future research will quantify the association between population density and rainfall on dengue incidence. This will allow health authorities to take a more proactive approach for dengue control., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Dengue is a vector-borne disease affected by meteorological factors and is commonly recorded from ground stations. Data from ground station have limited spatial representation and accuracy, which can be overcome using satellite-based Earth Observation (EO) recordings instead. EO-based meteorological recordings can help to provide a better understanding of the correlations between meteorological variables and dengue cases. This paper aimed to first validate the satellite-based (EO) data of temperature, wind speed, and rainfall using ground station data. Subsequently, we aimed to determine if the spatially matched EO data correlated with dengue fever cases from 2011 to 2019 in Malaysia. EO data were spatially matched with the data from four ground stations located at states and districts in the central (Selangor, Petaling) and east coast (Kelantan, Kota Baharu) geographical regions of Peninsular Malaysia. Spearman's rank-order correlation coefficient (ρ) was performed to examine the correlation between EO and ground station data. A cross-correlation analysis with an eight-week lag period was performed to examine the magnitude of correlation between EO data and dengue case across the three time periods (2011-2019, 2015-2019, 2011-2014). The highest correlation between the ground-based stations and corresponding EO data were reported for temperature (mean ρ = 0.779), followed by rainfall (mean ρ = 0.687) and wind speed (mean ρ = 0.639). Overall, positive correlations were observed between weekly dengue cases and rainfall for Selangor and Petaling across all time periods with significant correlations being observed for the period from 2011 to 2019 and 2015 to 2019. In addition, positive significant correlations were also observed between weekly dengue cases and temperature for Kelantan and Kota Baharu across all time periods, while negative significant correlations between weekly dengue cases and temperature were observed in Selangor and Petaling across all time periods. Overall negative correlations were observed between weekly dengue cases and wind speed in all areas from 2011 to 2019 and 2015 to 2019, with significant correlations being observed for the period from 2015 to 2019. EO-derived meteorological variables explained 48.2% of the variation in dengue cases in Selangor. Moderate to strong correlations were observed between meteorological variables recorded from EO data derived from satellites and ground stations, thereby justifying the use of EO data as a viable alternative to ground stations for recording meteorological variables. Both rainfall and temperature were found to be positively correlated with weekly dengue cases; however, wind speed was negatively correlated with dengue cases.

When era big data has reached to Malaysia, our government realized that all data are streaming all over the Internet from various data sources like sensors, social media data, excel spreadsheets, reviews, customer data, and etc. There are a lot data from our government need to be analysis which is can help decision making in the future. This Malaysia Open data can be analysis to help the government to predict what the next planning to do. In this paper, we use the Malaysia Open Data Government Portal about Malaysian Dengue Hotspot from 2010 until 2015. In the days, machine learning algorithms and technologies were mostly used by scientists, tech geeks or domain experts. However, several organizations are now using machine learning online and offline tool to make these technologies available to the masses to people outside. Online and offline tool make it easy for developers to apply machine learning to a dataset so as to add predictive features to their applications. In this paper, we used BigML which it provide online platform to integrate machine learning in real world applications and to predict the most popular place for Dengue to get an early warning and awareness to the people. BigML use the decision tree algorithms to do data analytics and prediction the popular place. In this case, we are using BigML to predict the place which always dengue occur in Malaysia which is also called as hotspot. [ABSTRACT FROM AUTHOR]

A well-developed healthcare system, decent access to clean water and sanitation, and programmes to eliminate poverty and build modern infrastructure are essential components to create healthier Malaysia's population. Non-communicable diseases currently account for most of the mortality and morbidity, although communicable diseases such as dengue fever, avian flu and covid-19 still pose a threat. The World Health Organization (WHO) identified COVID-19 is a rare pneumonia disease that originated in Wuhan, on January 12, 2020, before it became an outbreak in all countries including Malaysia. The requirement of a precise mapping and Cartography for the accurate disease mapping and data management are crucial due to a precise map gives higher resolution of the data and for more specific data analysis, interpretation and decision making process. In Malaysia, there no specific report on precise mapping for health applications, and it is therefore this paper is to identify the potential criteria and factors needed for precise health mapping applications. A precise health mapping is essential to create a precise risk map towards the surveillance and signal detection, predicting future risk, targeted interventions, and understanding disease phenomena. [ABSTRACT FROM AUTHOR]

The incidence of dengue cases and dengue death has grown-up dramatically around the world in recent decades. Recently, the number of reported cases, especially in Malaysia continued to increase. Over the year, many researchers try to estimate the number of deaths that cause by dengue. One of the methods in Biostatistics is ARIMA method which is involving time series analysis. Time series analysis commonly referred to any analysis which involved in a time series data. If the continuous observation is dependable, then the values that will come are able to be forecasted from the previous observation. The objective of this research paper is to forecast the number of dengue deaths, to describe the behavior of the time series data and afterwards made use of skilled statistical techniques for estimation, forecasting but also the controlling. In this paper the recognition of concerning the SARIMA (p,d,q) (P,D,Q)15 was given attention through the approach to the Autocorrelation Function ACF and Partial Autocorrelation Function (PACF) theory plot. SARIMA (2,1,0) (0,1,1)15 is being selected as the best model to represent the dengue death data. The gained model will be used as a tool for the prediction of the dengue death. [ABSTRACT FROM AUTHOR]

An estimated 105 million dengue infections occur per year across 120 countries, where traditional vector control is the primary control strategy to reduce contact between mosquito vectors and people. The ongoing sars-cov-2 pandemic has resulted in dramatic reductions in human mobility due to social distancing measures; the effects on vector-borne illnesses are not known. Here we examine the pre and post differences of dengue case counts in Malaysia, Singapore and Thailand, and estimate the effects of social distancing as a treatment effect whilst adjusting for temporal confounders. We found that social distancing is expected to lead to 4.32 additional cases per 100,000 individuals in Thailand per month, which equates to 170 more cases per month in the Bangkok province (95% CI: 100–242) and 2008 cases in the country as a whole (95% CI: 1170–2846). Social distancing policy estimates for Thailand were also found to be robust to model misspecification, and variable addition and omission. Conversely, no significant impact on dengue transmission was found in Singapore or Malaysia. Across country disparities in social distancing policy effects on reported dengue cases are reasoned to be driven by differences in workplace-residence structure, with an increase in transmission risk of arboviruses from social distancing primarily through heightened exposure to vectors in elevated time spent at residences, demonstrating the need to understand the effects of location on dengue transmission risk under novel population mixing conditions such as those under social distancing policies. Author summary: Significant healthcare burdens arise from dengue and traditional vector control is the primary control strategy to reduce dengue transmission potential. The ongoing sars-cov-2 pandemic has resulted in dramatic reductions in human mobility due to social distancing measures; the effects on vector-borne illnesses are not known. This paper examines the pre and post differences of dengue case counts in Malaysia, Singapore and Thailand, and estimate the effects of social distancing as a treatment effect whilst accounting for temporal confounders. We found that social distancing is expected to lead to an increase in the number of cases in Thailand, with the largest increase arising from Bangkok province. Social distancing policy estimates for Thailand were also found to be robust in sensitivity analysis. Conversely, no significant impact on dengue transmission was found in Singapore or Malaysia. Across country disparities in social distancing policy effects on reported dengue cases are reasoned to be driven by differences in workplace-residence structure, with an increase in transmission risk of arboviruses from social distancing primarily through heightened exposure to vectors in elevated time spent at residences, demonstrating the need to understand the effects of location on dengue transmission risk under novel population mixing conditions such as those under social distancing policies. [ABSTRACT FROM AUTHOR]

In the study of disease mapping, relative risk estimation is the focus of analysis. Many methods have been introduced to estimate relative risk. In this paper, one of the common spatial models known as Besag, York and Mollié (BYM) model is discussed, and its application to dengue data for epidemiology weeks 1 to 52 of the year 2013 for 16 states in Malaysia is studied. Findings show that Selangor has the highest relative risk of dengue in comparison with other states. Data on the estimated relative risks are presented in the form of risk maps which can be used as a tool for the prevention and control of dengue. [ABSTRACT FROM AUTHOR]

In this paper, we will start off by introducing the classical Ross-Macdonald model for vector-borne diseases which we use to describe the transmission of dengue between humans and Aedes mosquitoes in Shah Alam, which is a city and the state capital of Selangor, Malaysia. We will focus on analysing the effect of using the Mosquito Home System (MHS), which is an example of an autodissemination trap, in reducing the number of dengue cases by changing the Ross-Macdonald model. By using the national dengue data from Malaysia, we are able to estimate λ , which represents the initial growth rate of the dengue epidemic, and this allows us to estimate the number of mosquitoes in Malaysia. A mathematical expression is also constructed which allows us to estimate the potential number of breeding sites of Aedes mosquitoes. By using the data available from the MHS trial carried out in Section 15 of Shah Alam, we included the potential effect of the MHS into the dengue model and thus modelled the impact MHS has on the spread of dengue within the trial area. We then extended our results to analyse the effect of the MHSs on reducing the number of dengue cases in the whole of Malaysia. A new model was constructed with a basic reproduction number, R , which allows us to identify the required MHSs coverage needed to achieve extinction in Malaysia. Numerical simulations and tables of results were also produced to illustrate our results.0,Mala MHS , which allows us to identify the required MHSs coverage needed to achieve extinction in Malaysia. Numerical simulations and tables of results were also produced to illustrate our results., Competing Interests: The authors declare that there are no conflicts of interest regarding the publication of this paper.

Spatio-temporal disease mapping models give a great worth in epidemiology, especially in describing the pattern of disease incidence across geographical space and time. This paper analyses the spatial and temporal variability of dengue disease rates based on generalized linear mixed models. For spatio-temporal study, the models incorporate spatially correlated random effects as well as temporal effects. In this study, two different spatial random effects are applied and compared. The first model is based on Leroux spatial model, while the second model is based on the stochastic partial differential equation approach. For the temporal effects, both models follow an autoregressive model of first-order model. The models are fitted within a hierarchical Bayesian framework with integrated nested Laplace approximation methodology. The main objective of this study is to compare both spatio-temporal models in terms of their ability in representing the disease phenomenon. The models are applied to weekly dengue fever data in Peninsular Malaysia reported to the Ministry of Health Malaysia in the year 2017 according to the district level. [ABSTRACT FROM AUTHOR]

Time series of counts occur in many different contexts, the counts being usually of certain events or objects in specified time intervals. In this paper we introduce a model called parameter-driven state-space model to analyse integer-valued time series data. A key property of such model is that the distribution of the observed count data is independent, conditional on the latent process, although the observations are correlated marginally. Our simulation shows that the Monte Carlo Expectation Maximization (MCEM) algorithm and the particle method are useful for the parameter estimation of the proposed model. In the application to Malaysia dengue data, our model fits better when compared with several other models including that of Yang et al. (2015) [ABSTRACT FROM AUTHOR]

Vector-borne infectious disease such as dengue fever (DF) has spread rapidly due to more suitable living environments. Considering the limited studies investigating the disease spread under climate change in South and Southeast Asia, this study aimed to project the DF transmission potential in 30 locations across four South and Southeast Asian countries. In this study, weekly DF incidence data, daily mean temperature, and rainfall data in 30 locations in Singapore, Sri Lanka, Malaysia, and Thailand from 2012 to 2020 were collected. The effects of temperature and rainfall on the time-varying reproduction number (Rt) of DF transmission were examined using generalized additive models. Projections of location-specific Rt from 2030s to 2090s were determined using projected temperature and rainfall under three Shared Socioeconomic Pathways (SSP126, SSP245, and SSP585), and the peak DF transmissibility and epidemic duration in the future were estimated. According to the results, the projected changes in the peak Rt and epidemic duration varied across locations, and the most significant change was observed under middle-to-high greenhouse gas emission scenarios. Under SSP585, the country-specific peak Rt was projected to decrease from 1.63 (95% confidence interval: 1.39–1.91), 2.60 (1.89–3.57), and 1.41 (1.22–1.64) in 2030s to 1.22 (0.98–1.51), 2.09 (1.26–3.47), and 1.37 (0.83–2.27) in 2090s in Singapore, Thailand, and Malaysia, respectively. Yet, the peak Rt in Sri Lanka changed slightly from 2030s to 2090s under SSP585. The epidemic duration in Singapore and Malaysia was projected to decline under SSP585. In conclusion, the change of peak DF transmission potential and disease outbreak duration would vary across locations, particularly under middle-to-high greenhouse gas emission scenarios. Interventions should be considered to slow down global warming as well as the potential increase in DF transmissibility in some locations of South and Southeast Asia. Author summary: Climate change has a significant impact worldwide, including the proliferation of infectious diseases in tropical areas. While the warmer and more humid living conditions in these regions are generally considered favorable for the transmission of vector-borne diseases, we argue that the effects of climate change on DF infection may vary across different locations. Unlike previous studies focusing primarily on the disease incidence, this study aims to estimate changes in peak DF transmissibility and the duration of disease epidemics in the future. By analyzing data from 30 locations in four tropical countries, we have found that changes in DF transmissibility and epidemic duration exhibit variations both within and between countries, particularly under the scenarios of moderate to high greenhouse gas emissions. In light of these findings, we recommend conducting location-specific evaluations of DF transmissibility under the influence of climate change, as well as implementing targeted interventions to mitigate the potential increase in DF transmission rates in specific tropical locations. [ABSTRACT FROM AUTHOR]

Few publications consider the estimation of relative risk for vector-borne infectious diseases. Most of these articles involve exploratory analysis that includes the study of covariates and their effects on disease distribution and the study of geographic information systems to integrate patient-related information. The aim of this paper is to introduce an alternative method of relative risk estimation based on discrete time–space stochastic SIR-SI models (susceptible–infective–recovered for human populations; susceptible–infective for vector populations) for the transmission of vector-borne infectious diseases, particularly dengue disease. First, we describe deterministic compartmental SIR-SI models that are suitable for dengue disease transmission. We then adapt these to develop corresponding discrete time–space stochastic SIR-SI models. Finally, we develop an alternative method of estimating the relative risk for dengue disease mapping based on these models and apply them to analyse dengue data from Malaysia. This new approach offers a better model for estimating the relative risk for dengue disease mapping compared with the other common approaches, because it takes into account the transmission process of the disease while allowing for covariates and spatial correlation between risks in adjacent regions. [ABSTRACT FROM AUTHOR]

Dengue fever, an arbovirus disease transmitted by Aedes mosquitoes, has recently spread rapidly, especially in the tropical countries of the Americas and Asia-Pacific regions. It is endemic in Malaysia, with an annual average of 37,937 reported dengue cases from 2007 to 2012. This study measured the overall economic impact of dengue in Malaysia, and estimated the costs of dengue prevention. In 2010, Malaysia spent US$73.5 million or 0.03% of the country's GDP on its National Dengue Vector Control Program. This spending represented US$1,591 per reported dengue case and US$2.68 per capita population. Most (92.2%) of this spending occurred in districts, primarily for fogging. A previous paper estimated the annual cost of dengue illness in the country at US$102.2 million. Thus, the inclusion of preventive activities increases the substantial estimated cost of dengue to US$175.7 million, or 72% above illness costs alone. If innovative technologies for dengue vector control prove efficacious, and a dengue vaccine was introduced, substantial existing spending could be rechanneled to fund them., (© The American Society of Tropical Medicine and Hygiene.)

• Dengue model with the temperature effect, using integer-order and the fractional-order differential equations is proposed. • The optimal temperature for a maximum dengue transmission is around 32∘C. • The backward bifurcation occurs in the presence of dengueinduced death rate. • The solutions of the aquatic stage of the integer-order model exhibit oscillatory behaviour whenever dengue is endemic. • Fractional-order dengue model provides stable solutions compared to the integer-order model. In this study, a deterministic mathematical model of the dengue transmission is developed by considering the effect of temperature on the transmission dynamics. It has a locally asymptotically stable disease-free equilibrium (DFE) point whenever the basic reproduction number (R 0) is less than unity. This model has shown a possibility of backward bifurcation, where the stable DFE coexists with a stable endemic equilibrium point when R 0 < 1. Using the entomological data of the Aedes mosquito population and the experimental data of the dengue transmission in Malaysia, R 0 is evaluated at different temperatures, given that at 32∘C, R 0 attain its maximum value. The solutions of the model show an oscillatory behaviour. Although the oscillations are unobservable in the state variable, they are present in the numerical solution. Finally, a fractional analogue of the dengue model is presented, and numerical solutions are performed to make a comparison with the integer-order model. A comparison of the two results reveals that the fractional-order model provides stable solutions as the oscillatory behaviour can be dampened. This paper provides numerical evidence that the dengue virus can spread in temperate areas where it is no longer limited to tropical and subtropical regions, and suggests that the fractional-order approach can be a great alternative in modelling dengue transmission dynamics. [ABSTRACT FROM AUTHOR]

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.

Dengue is a serious mosquito borne disease common in tropical and sub-tropical countries including Malaysia. There is at present a lack of specific treatment and an effective tetravalent vaccine against dengue. The control of dengue depends solely on the suppression of the two most important vectors namely, Aedes aegypti and Ae albopictus. Despite intensive and extensive control efforts by health agencies, the disease continues to spread. This paper updates various innovations on control of dengue vectors. Gene-based sterile insect technique using the RIDL technology for both Aedes aegypti & Ae albopictus control has now been actively researched and field trials are pursued to evaluate the effectiveness of the technology. The release of Wolbachia-infected Ae aegypti is another dengue control innovation. The infected mosquito cannot support development of dengue virus and has shorter life span. Other innovations include: auto-dissemination of insect control agents using ovitrap, autocidal adult and larva trap, outdoor residual spraying, insecticidal paint and biocontrol agent. In other innovation, outbreak prediction capability is enhanced by developing model based on environmental data and analysis utilising neural network. [ABSTRACT FROM AUTHOR]

Background: Dengue fever is endemic in Malaysia, with frequent major outbreaks in urban areas. The major control strategy relies on health promotional campaigns aimed at encouraging people to reduce mosquito breeding sites close to people's homes. However, such campaigns have not always been 100% effective. The concept of self-efficacy is an area of increasing research interest in understanding how health promotion can be most effective. This paper reports on a study of the impact of self-efficacy on dengue knowledge and dengue preventive behaviour., Methods and Findings: We recruited 280 adults from 27 post-outbreak villages in the state of Terengganu, east coast of Malaysia. Measures of health promotion and educational intervention activities and types of communication during outbreak, level of dengue knowledge, level and strength of self-efficacy and dengue preventive behaviour were obtained via face-to-face interviews and questionnaires. A structural equation model was tested and fitted the data well (χ(2) = 71.659, df = 40, p = 0.002, RMSEA = 0.053, CFI = 0.973, TLI = 0.963). Mass media, local contact and direct information-giving sessions significantly predicted level of knowledge of dengue. Level and strength of self-efficacy fully mediated the relationship between knowledge of dengue and dengue preventive behaviours. Strength of self-efficacy acted as partial mediator in the relationship between knowledge of dengue and dengue preventive behaviours., Conclusions: To control and prevent dengue outbreaks by behavioural measures, health promotion and educational interventions during outbreaks should now focus on those approaches that are most likely to increase the level and strength of self-efficacy.

The Water-associated Disease Index (WADI) was developed to identify and visualize vulnerability to different water-associated diseases by integrating a range of social and biophysical determinants in map format. In this study vulnerability is used to encompass conditions of exposure, susceptibility, and differential coping capacity to a water-associated health hazard. By assessing these conditions, the tool is designed to provide stakeholders with an integrated and long-term understanding of subnational vulnerabilities to water-associated disease and contribute to intervention strategies to reduce the burden of illness. The objective of this paper is to describe and validate the WADI tool by applying it to dengue. A systemic ecohealth framework that considers links between people, the environment and health was applied to identify secondary datasets, populating the index with components including climate conditions, land cover, education status and water use practices. Data were aggregated to create composite indicators of exposure and of susceptibility in a Geographic Information System (GIS). These indicators were weighted by their contribution to dengue vulnerability, and the output consisted of an overall index visualized in map format. The WADI was validated in this Malaysia case study, demonstrating a significant association with dengue rates at a sub-national level, and illustrating a range of factors that drive vulnerability to the disease within the country. The index output indicated high vulnerability to dengue in urban areas, especially in the capital Kuala Lumpur and surrounding region. However, in other regions, vulnerability to dengue varied throughout the year due to the influence of seasonal climate conditions, such as monsoon patterns. The WADI tool complements early warning models for water-associated disease by providing upstream information for planning prevention and control approaches, which increasingly require a comprehensive and geographically broad understanding of vulnerability for implementation.

Dengue fever is a recurring public health problem afflicting thousands of Malaysians annually. In this paper, the risk map for dengue fever in the peninsular Malaysian states of Selangor and Kuala Lumpur was modelled based on co-kriging and geographical information systems. Using population density and rainfall as the model's only input factors, the area with the highest risk for dengue infection was given as Gombak and Petaling, two districts located on opposite sides of Kuala Lumpur city that was also included in the risk assessment. Comparison of the modelled risk map with the dengue case dataset of 2010, obtained from the Ministry of Health of Malaysia, confirmed that the highest number of cases had been found in an area centred on Kuala Lumpur as predicted our risk profiling.

Aim: This study aims to detect the spatial cluster, the temporal cluster, as well as the spatio-temporal cluster of high dengue disease incidence in Peninsular Malaysia for the year 2015 until 2017. As dengue disease cases are properly recorded according to their location and time, cluster analysis of the dengue disease based on its spatial, temporal, as well as spatio-temporal similarity would be more efficient. Subject and Methods: Clustering is one of the essential components in disease mapping that could be helpful in controlling diseases, especially those related to infectious disease. It is used to group large sets of disease data based on their similarity. The clustering method that has been used in this study is Kulldorff's retrospective space-time scan statistics. The data used in this study are weekly dengue disease cases in districts of Peninsular Malaysia from 2015 to 2017. Results and Conclusions: From the results, there were significant spatial cluster, temporal cluster, and spatio-temporal clusters of dengue disease incidence in Peninsular Malaysia for 2015, 2016, and 2017. Results from spatial clustering focused on areas in Selangor as the dengue clustered area and results from temporal clustering revealed the weeks in October until December as the dengue clustered period. Meanwhile, the spatio-temporal clustering demonstrated that there exists another clustered region of high dengue disease incidence in different areas and time periods. [ABSTRACT FROM AUTHOR]

Prior to COVID-19, dengue was an important public health problem in Malaysia. Due to the movement control order imposed by the Malaysian government to curb the COVID-19 transmission, a study predicted that mosquito-borne diseases would increase during lockdown and partial lockdown seasons. Thus, this study aims to determine the current situation of dengue incidence during the pre-COVID-19 pandemic (2019) and during the COVID-19 pandemic (2020 and 2021). We compared the number of laboratory-confirmed cases in the pre-COVID19 year (2019) and during the COVID-19 pandemic (2020 and 2021). In addition to that, we characterized the clinical manifestation, dengue serotype and viremia levels of dengue patients that were admitted to the Hospital Cancelor Tuanku Muhriz. We found a significant decrease in the number of laboratory-confirmed cases between COVID-19 pandemic and the pre-covid period (p2020=0.064; p2021< 0.001). In this study, we found DENV 4 serotype was the most common serotype in dengue patients admitted to our hospital. There was no significant correlation between DENV serotype/viremia level with clinical manifestation of dengue fever and dengue with warning signs. However, patients infected with DENV4 had the highest viral load compared to patients infected with other serotypes. We also found high viremia levels were significantly associated with the febrile phase. [ABSTRACT FROM AUTHOR]

The release of over 6,000 genetically modified mosquitoes (GMM) into uninhabited Malaysian forests in 2010 was a frantic step on the part of the Malaysian government to combat the spread of dengue fever. The field trial was designed to control and reduce the dengue vector by producing offspring that die in the early developmental stage, thus decreasing the local Aedes aegypti population below the dengue transmission threshold. However, the GMM trials were discontinued in Malaysia despite being technologically feasible. The lack of systematic studies in terms of cost-benefit analysis, questionable research efficacy and safety-related concerns might have contributed to the termination of the field trial. Hence, this research aims to evaluate the feasibility of GMM release in Malaysia by using a holistic approach based on an Islamic ethical-legal assessment under the maslahah-mafsadah (benefit-risk) concept. Three main strategies based on the maslahah-mafsadah concept approach have been applied: 1) an evidence-based approach, 2) an impact-based approach and, 3) a priority approach. The analysis concluded that GMM could be categorised as zanniyyah (probable). GMM is a promising alternative for dengue control, but many issues must be addressed before its widespread adoption. [ABSTRACT FROM AUTHOR]

Dengue fever has long been a community health problem in tropical countries. Dengue virus is a crucial cause of disease in international tourists, with a rising number of them returning from dengue-endemic countries infected with dengue fever. This study analyses the impact of international tourist arrivals on economic growth moderated by dengue fever cases in Malaysia from 2014 until 2020. This study was carried out using secondary monthly data for dengue fever cases, gross domestic product (GDP), and international tourist arrivals. A correlation test was used to analyse the correlation between the independent, dependent and moderating variables. Granger causality test was employed to determine the causality between the selected three variables, dengue fever cases, international tourist arrivals, and economic growth. The results reveal a significant correlation between dengue fever cases, tourist arrivals, and economic growth. Between 2017 and 2018, higher international tourist arrivals led to lower economic growth under dengue disease hazards in Malaysia. Furthermore, dengue fever risk is found to have a positive relationship with international tourist arrivals and vice versa. The findings show a causality effect between the selected variables. The selected three indicators drive each other in the period study. In line with the government's strategy to promote the Malaysian tourism industry, prevention and recovery policies should be planned considering the number of dengue cases and economic factors. [ABSTRACT FROM AUTHOR]

Background Due to an ageing population, dengue among older patients is encountered more frequently in many countries. Our study aimed to explore the clinico-laboratory parameters and outcomes among dengue-infected older patients in comparison with younger patients. Methods This retrospective chart review involved dengue patients with dengue non-structural protein 1 (NS1) antigen positivity admitted to a tertiary hospital in Malaysia from January to July 2015. A comparison was made between older people (aged ≥60 y) and others. Results Among 406 dengue patients, 43 (10.6%) were older people. Older dengue patients were less likely to present with persistent vomiting (adjusted OR [AOR] 0.247, 95% CI 0.093 to 0.656, p=0.005), while restlessness and confusion were more common at presentation (AOR 3.356, 95% CI 1.024 to 11.003, p=0.046). Older patients had significantly lower albumin upon admission (38 vs 40 g/L, p=0.036) and during hospital stay (35 vs 37 g/L, p=0.015). Compared with younger patients, older patients were more likely to have experienced nadir platelet counts of <50×109/L (AOR 2.897, 95% CI to 1.176 to 7.137, p=0.021). They were also more likely to require an extended hospital stay (AOR 3.547, 95% CI 1.575 to 7.986, p=0.002). Conclusions Diagnosis of dengue in older people may be challenging because of atypical presentations. Increased vigilance is necessary as there is an increased tendency to develop severe thrombocytopenia, hypoalbuminemia and prolonged hospitalisation in older people. [ABSTRACT FROM AUTHOR]

Dengue is a mosquito-borne disease that causes high mortality and fatality rate among humans. The disease and the virus are spread through female Ae. aegypti and Ae. albopictus. 176 Modified Sticky Ovitraps (MSO) were installed in six blocks of high-rise apartment buildings in Petaling Jaya, Selangor. The specimens were collected throughout a duration of 26 weeks. NS1 dengue antigen kit was used to detect dengue antigen in mosquitoes, and positive mosquitoes were serotyped using Reverse Transcriptase-PCR, followed by Multiplex-PCR. The relationship between the number of Aedes mosquitoes and meteorological parameters was also determined. The association between the number of Aedes spp. captured, dengue cases, and positive specimens was also evaluated in this study. A total of 243 adult mosquitoes were successfully captured using MSO, with 95.1% (231) of the mosquitoes being Ae. aegypti, while 4.1% (10) and 0.8% (2) were Ae. albopictus and a mixed Aedes species, respectively. The molecular detection of the dengue virus showed that only 2 individual specimens of Ae. aegypti were positive, with one specimen being a dual serotype of DEN-II and IV, and another specimen was DENV-II. The weekly number of Aedes spp. captured correlated positively with Tmax, Tmin, and Tmean, and correlated negatively with RF and RH. The significant and useful data obtained from this study can be utilized in dengue vector management by local health authorities. [ABSTRACT FROM AUTHOR]

Dengue is a major public health threat in Malaysia, which is known for the hyperendemicity with all the four serotypes of the dengue virus circulating concurrently. Annual dengue cases reported were 43,000 cases for 2013, and this imposed a heavy toil on the resources for dengue prevention and control program. The objective of mapping in our study is to determine the spatial clustering of the dengue cases and to identify the areas that are vulnerable to dengue outbreaks. A Geographical Information System (GIS) was used to assess the vulnerability of Seremban district. Dengue data were obtained from the Ministry of Health. We determined the spatial distribution, the average distance of dengue cases and identified hotspots areas using the Moran-'s I, Average Nearest Neighbourhood (ANN), Kernel density estimation. Vulnerability to dengue was assessed with the spatial temporal analyses and Local Indicator for Spatial Autocorrelation (LISA). From 2003-2009 Seremban recorded 6076 dengue cases. Moran-'s I showed the cases occurred in clusters with a Z-score of 16.384 (p<0.001). ANN 0.264 (p<0.001) indicated the mean distance between every dengue case was 55 meters. Kernel density estimation showed hotspots of dengue were concentrated in two subdistricts. This paper discusses how spatial-temporal approach can be used to assess the vulnerability of Seremban to dengue where control activities can be more focused to these high risk areas. Mapping the dengue distribution using spatial-temporal approach is useful and guides the public health management of dengue. [ABSTRACT FROM AUTHOR]

Dengue remains a major public threat and existing dengue control/surveillance programs lack sensitivity and proactivity. More efficient methods are needed. A cluster randomized controlled trial was conducted for 18 months to determine the efficacy of using a combination of gravid oviposition sticky (GOS) traps and dengue non-structural 1 (NS1) antigen for early surveillance of dengue among Aedes mosquito. Eight residential apartments were randomly assigned into intervention and control groups. GOS traps were placed at the intervention apartments weekly to trap Aedes mosquitoes and these tested for dengue NS1 antigen. When dengue-positive pool was detected, the community were notified and advised to execute protective measures. Fewer dengue cases were recorded in the intervention group than the control. Detection of NS1-positive mosquitoes was significantly associated with GOS Aedes index (rs = 0.68, P < 0.01) and occurrence of dengue cases (rs = 0.31, P < 0.01). Participants' knowledge, attitude, and practice (KAP) toward dengue control indicated significant improvement for knowledge (P < 0.01), practice (P < 0.01) and total scores (P < 0.01). Most respondents thought this surveillance method is good (81.2%) and supported its use nationwide. Thus, GOS trap and dengue NS1 antigen test can supplement the current dengue surveillance/control, in alignment with the advocated integrated vector management for reducing Aedes-borne diseases. [ABSTRACT FROM AUTHOR]

Background: A recent approach in controlling dengue is by using the Wolbachia-infected Aedes mosquito (WiAM). The approach has been reported to be more effective than traditional methods, such as fogging. Therefore, it is imperative to assess the factors predicting its acceptance among stakeholders before implementing this technology more widely in Malaysia.Methods: The survey data were collected from two primary stakeholder groups using a stratified random sampling technique. The two primary stakeholder groups were scientists (n = 202) and the public (n = 197) in the Klang Valley region of Malaysia, a hot spot area known for the high rate of dengue cases. The respondents answered questions on a seven-point Likert scale survey regarding trust in key players, attitudes toward nature versus materialism, religiosity, perceived benefits, perceived risks, attitudes, and intentions. The data were analyzed using Smart Partial Least Square (SmartPLS) software (version 3.2.6) to determine the predictors influencing attitudes and intentions to support the use of WiAM technology.Results: The results indicated a strong positive relationship between attitudes and intentions to support the use of WiAM (β = 0.676, p < 0.001). The most important significant predictor for attitudes was perceived benefits (β = 0.493, p < 0.001), followed by perceived risks (β = - 0.080, p = 0.048). Trust in key players, attitudes toward nature versus material, and religiosity had indirect relationships with attitudes through the perceived benefits and risks.Conclusions: The identified predictors can serve as indicators for the decision-making process regarding WiAM implementation in Malaysia and other developing countries with similar demographics and cultures. [ABSTRACT FROM AUTHOR]

Introduction. Dengue, a vector-borne viral illness, shows worldwide widening spatial distribution beyond its point of origination, namely, the tropical belt. The persistent hyperendemicity in Malaysia has resulted in the formation of the dengue early warning system. However, weather variables are yet to be fully utilized for prevention and control activities, particularly in east-coast peninsular Malaysia where limited studies have been conducted. We aim to provide a time-based estimate of possible dengue incidence increase following weather-related changes, thereby highlighting potential dengue outbreaks. Method. All serologically confirmed dengue patients in Kelantan, a northeastern state in Malaysia, registered in the eDengue system with an onset of disease from January 2016 to December 2018, were included in the study with the exclusion of duplicate entry. Using a generalized additive model, climate data collected from the Kota Bharu weather station (latitude 6°10 ′ N, longitude 102°18 ′ E) was analysed with dengue data. Result. A cyclical pattern of dengue cases was observed with annual peaks coinciding with the intermonsoon period. Our analysis reveals that maximum temperature, mean temperature, rainfall, and wind speed have a significant nonlinear effect on dengue cases in Kelantan. Our model can explain approximately 8.2% of dengue incidence variabilities. Conclusion. Weather variables affect nearly 10% of the dengue incidences in Northeast Malaysia, thereby making it a relevant variable to be included in a dengue early warning system. Interventions such as vector control activities targeting the intermonsoon period are recommended. [ABSTRACT FROM AUTHOR]

Outdoor Residual Spraying (ORS) technique is a complementary preventive measure for dengue. The alarming number of dengue cases in Malaysia requires an alternative method to control dengue besides the traditional method such as fogging. However, the introduction of new technologies depends on social acceptance. Therefore, this study was important to determine the factors that influence stakeholders' attitudes towards the ORS and the moderating factor. A validated instrument was used to randomly interview 399 respondents representing two stakeholder groups which consist of scientists, and the public in Klang Valley, Malaysia. The findings revealed that the stakeholders claimed to have a high degree of religiosity, a high level of trust in the key players, perceived ORS as having high benefits, and displayed highly positive attitudes towards the ORS. The attitudes model towards the ORS model was developed using the SmartPLS software version. The perceived benefit was endorsed as the most important direct predictor of attitudes towards the ORS (ß = 0.618, P<0.001), followed by trust in the key players (ß = 0.151, P<0.001). It is also interesting to note that religiosity served as a moderator for the association between perceived benefit (ß = 0.075, P = 0.024) and perceived risk (ß = 0.114, P = 0.006) with attitudes towards the ORS. The identified predictor factors of stakeholders' attitudes toward the ORS and the moderating factor can serve as indicators for social acceptance of ORS in developing countries. These indicators can help the policymakers in decision making to implement this technique. Author summary: The ups and downs of dengue cases require the Outdoor Residual Spraying (ORS) technique as an alternative method to control dengue in Malaysia. However, the introduction of ORS depends on stakeholders' acceptance. Here, the purpose of this study was to determine the factors that predict attitude to ORS and the role of religiosity as a moderator. The results indicate positive responses for implementing the ORS as a suitable technique to control dengue in Malaysia. Perceived benefit emerged as the most significant direct predictor of attitude towards the ORS (β = 0.618, p<0.001), which they viewed this technique as less risky. Trust in key players had a significant positive relationship with attitudes towards the ORS that makes this factor the second most important direct predictor (β = 0.151, p<0.001). Interestingly, the religiosity factor significantly moderated the relationship between perceived benefit and risk with attitudes towards the ORS. This study also showed the role played by both perceived benefit and risk as mediating factors. [ABSTRACT FROM AUTHOR]

Background: In common with many South East Asian countries, Malaysia is endemic for dengue. Dengue control in Malaysia is currently based on reactive vector management within 24 h of a dengue case being reported. Preventive rather than reactive vector control approaches, with combined interventions, are expected to improve the cost-effectiveness of dengue control programs. The principal objective of this cluster randomized controlled trial is to quantify the effectiveness of a preventive integrated vector management (IVM) strategy on the incidence of dengue as compared to routine vector control efforts.Methods: The trial is conducted in randomly allocated clusters of low- and medium-cost housing located in the Federal Territory of Kuala Lumpur and Putrajaya. The IVM approach combines: targeted outdoor residual spraying with K-Othrine Polyzone, deployment of mosquito traps as auto-dissemination devices, and community engagement activities. The trial includes 300 clusters randomly allocated in a 1:1 ratio. The clusters receive either the preventive IVM in addition to the routine vector control activities or the routine vector control activities only. Epidemiological data from monthly confirmed dengue cases during the study period will be obtained from the Vector Borne Disease Sector, Malaysian Ministry of Health e-Dengue surveillance system. Entomological surveillance data will be collected in 12 clusters randomly selected from each arm. To measure the effectiveness of the IVM approach on dengue incidence, a negative binomial regression model will be used to compare the incidence between control and intervention clusters. To quantify the effect of the interventions on the main entomological outcome, ovitrap index, a modified ordinary least squares regression model using a robust standard error estimator will be used.Discussion: Considering the ongoing expansion of dengue burden in Malaysia, setting up proactive control strategies is critical. Despite some limitations of the trial such as the use of passive surveillance to identify cases, the results will be informative for a better understanding of effectiveness of proactive IVM approach in the control of dengue. Evidence from this trial may help justify investment in preventive IVM approaches as preferred to reactive case management strategies.Trial Registration: ISRCTN ISRCTN81915073 . Retrospectively registered on 17 April 2020. [ABSTRACT FROM AUTHOR]

Background: In Malaysia, dengue remains a top priority disease and usage of insecticides is the main method for dengue vector control. Limited baseline insecticide resistance data in dengue hotspots has prompted us to conduct this study. The present study reports the use of a map on the insecticide susceptibility status of Aedes aegypti and Aedes albopictus to provide a quick visualization and overview of the distribution of insecticide resistance. Method and results: The insecticide resistance status of Aedes populations collected from 24 dengue hotspot areas from the period of December 2018 until June 2019 was proactively monitored using the World Health Organization standard protocol for adult and larval susceptibility testing was conducted, together with elucidation of the mechanisms involved in observed resistance. For resistance monitoring, susceptibility to three adulticides (permethrin, deltamethrin, and malathion) was tested, as well as susceptibility to the larvicide, temephos. Data showed significant resistance to both deltamethrin and permethrin (pyrethroid insecticides), and to malathion (organophosphate insecticide) in all sampled Aedes aegypti populations, while variable resistance patterns were found in the sampled Aedes albopictus populations. Temephos resistance was observed when larvae were tested using the diagnostic dosage of 0.012mg/L but not at the operational dosage of 1mg/L for both species. Conclusion: The present study highlights evidence of a potential threat to the effectiveness of insecticides currently used in dengue vector control, and the urgent requirement for insecticide resistance management to be integrated into the National Dengue Control Program. Author summary: Insecticide resistance may threaten the efficacy of insecticides currently used in the dengue vector control program. These current findings reveal widespread insecticide resistance in Aedes aegypti and Aedes albopictus sampled from dengue hotspots. This screening provides comprehensive data on insecticide resistance to insecticides commonly used in dengue vector control programs. The mapping approach utilized in this present study facilitates easy visualization of the resistance distribution in dengue vectors across many dengue hotspots. Therefore, it could hence be beneficial to the Ministry of Health in managing the threat of resistance before it compromises current dengue vector control strategies. [ABSTRACT FROM AUTHOR]

Background A periodic serosurvey of dengue seroprevalence is vital to determine the prevalence of dengue in countries where this disease is endemic. This study aimed to determine the prevalence of dengue immunoglobulin G (IgG) seropositivity among healthy Malaysian adults living in urban and rural areas. Methods A total of 2598 serum samples (1417 urban samples, 1181 rural samples) were randomly collected from adults ages 35–74 y. The presence of the dengue IgG antibody and neutralising antibodies to dengue virus (DENV) 1–4 was determined using enzyme-linked immunosorbent assay and the plaque reduction neutralisation test assay, respectively. Results The prevalence of dengue IgG seropositivity was 85.39% in urban areas and 83.48% in rural areas. The seropositivity increased with every 10-y increase in age. Ethnicity was associated with dengue seropositivity in urban areas but not in rural areas. The factors associated with dengue seropositivity were sex and working outdoors. In dengue IgG-positive serum samples, 98.39% of the samples had neutralising antibodies against DENV3, but only 70.97% of them had neutralising antibodies against DENV4. Conclusion The high seroprevalence of dengue found in urban and rural areas suggests that both urban and rural communities are vital for establishing and sustaining DENV transmission in Malaysia. [ABSTRACT FROM AUTHOR]

Introduction Dengue fever is an arthropod-borne viral disease that has become endemic in most tropical countries. In 2014, Malaysia reported 108 698 cases of dengue fever with 215 deaths which increased tremendously compared to 49 335 cases with 112 deaths in 2008 and 30 110 cases with 69 deaths in 2009. This study aimed to identify the best method in determining dengue outbreak threshold for Negeri Sembilan as it can help to send uniform messages to inform the general public and make the outbreak analysis comparable within and between countries. Methods Using retrospective Negeri Sembilan country dataset from 1st epid week of 2011 till the 52nd epid week of 2016. The data were split into two periods: 1) a 3-year historic period (2011-2013), used to calibrate and parameterise the model, and a 1-year evaluation period (2014); 2) a 2-year historic period (2014-2016), used to calibrate and parameterise the model, and a 1-year evaluation period (2016), used to test the model. E-dengue is a registration system for confirmed dengue cases dengue by Ministry of Health. Data included were details of cases, district locality, records on the outbreak and epidemiological week (Sunday to Saturday) captured using the Excel spreadsheet. Analysis method included endemic channel method, moving average or deviation bar chart and recent mean. Results Seremban as big district and facing with heavy dengue cases, all three methods (endemic curve, current mean and moving mean) showed promising results. Meanwhile comparing with small district of Port Dickson and Tampin with fewer dengue cases and outbreak recorded, the suitable method is by using endemic channel for epidemic threshold. Conclusions Simpler methods such as the endemic channel, recent mean and moving mean may be more appropriate in urban district. Whereas in rural or district with minimal dengue cases, Endemic Channel would be the most suitable method for epidemic threshold. However, both methods require a consistent updated graph threshold as time progress. [ABSTRACT FROM AUTHOR]

BACKGROUND Papaya is widely grown in Malaysia and normally only the fruits are consumed. Other parts of the plant such as leaves, roots, bark, peel, seeds and pulp are also known to have medicinal properties and have been used to treat various diseases. Papaya leaves also contain flavonoids, alkaloids phenolic compounds and cynogenetic compounds, and are also reported to be able to treat dengue fever. RESULTS: Studies were carried out on drying of papaya leaves using hot air (60, 70 and 80 °C), shade and freeze drying. Effective diffusivities were estimated ranging from 2.09 × 10−12 to 2.18 × 10−12 m2 s−1 from hot air drying, which are within the order of magnitudes reported for most agricultural and food products. The activation energy to initiate drying showed a relatively low value (2.11 kJ mol−1) as a result of the thin leave layer that eased moisture diffusion. In terms of total polyphenols content and antioxidant activities, freeze‐dried sample showed a significantly higher (P < 0.05) total polyphenols content [2158 mg gallic acid equivalent 100 g dry weight−1] and antioxidant activities [2,2'‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS) = 571 mg TE 100 g DW−1 and 2,2'‐diphenyl‐1‐picrylhydrazyl (DPPH) = 215 μg mg−1] compared to hot air and shade dried samples. CONCLUSION: Freeze dried sample retained the most total polyphenols content and showed the highest antioxidant activities in both ABTS and DPPH antioxidant assays. Hot air and shade drying are not conducive with repect to preserving the antioxidants as a result of possible thermal degradation at elevated temperatures and oxidations under prolonged drying condition. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

This study aims to assess the trends of dengue incidence and socio-demographic characteristics of reported dengue cases in Seremban district, Malaysia during the last decade. Secondary data on reported dengue cases during 2003-2011 were collected from the District Health Office, Seremban. Trend analysis was conducted to assess the status of dengue incidence and demographic distribution of the disease in the district. Annual incidence rates of the disease were also calculated and compared. The district experienced a total of 11,936 dengue infections during 2003-2011. It was found that majority of the reported cases were among the Malays (62%), followed by Chinese (17%) and Indians (15%). The age-specific incidence rate was highest in young adult and adult group (15-44 years), followed by middle-age group (45-59 years). The analysis also revealed that majority of the reported cases (on average, 79% per year) came from urban areas of the district which highlights the fact that dengue is still an urban public health problem in Seremban. The study findings provide the critical data and information on trends of dengue incidence and socio-demographic characteristics of reported dengue cases which might assist the public health authorities to achieve dengue mortality and morbidity reduction goals in the district. [ABSTRACT FROM AUTHOR]

Several sites, Z-7L, Z-5 and Z-14, in Sibu district, Sarawak, Malaysia, experienced intense dengue transmission in 2014 that continued into 2015. A pilot study with Bacillus thuringiensis israelensis (Bti) to control Aedes aegypti (L.) and Ae. albopictus (Skuse) was evaluated in Z-7L, a densely populated site of 12 ha. Bti treatments were conducted weekly from epidemiology week (EW) 24/2015 for 4 weeks, followed by fortnight treatments for 2 months, in addition to the routine control activities. Bti was directly introduced into potable containers and the outdoor artificial and natural containers were treated via a wide area spray application method using a backpack mister. Aedes indices significantly reduced during the treatment and post treatment phases, compared to the control site, Z-5 (p<0.05). A 51 fold reduction in the incidence rate per 100,000 population (IR) was observed, with one case in 25 weeks (EW 29–52). In Z-5 and Z-14, control sites, a 6 fold reduction in the IR was observed from EW 29–52. However, almost every week there were dengue cases in Z-14 and until EW 44 in Z-5. In 2016, dengue cases resurfaced in Z-7L from EW 4. Intensive routine control activities were conducted, but the IR continued to escalate. The wide area Bti spray misting of the outdoor containers was then included from EW 27 on fortnight intervals. A 6 fold reduction in IR was observed in the Bti treatment phase (EW 32–52) with no successive weekly cases after EW 37. However, in the control sites, there were dengue cases throughout the year from EW 1–52, particularly in Z-14. We feel that the wide area Bti spray application method is an integral component in the control program, in conjunction with other control measures carried out, to suppress the vector population in outdoor cryptic containers and to interrupt the disease transmission. [ABSTRACT FROM AUTHOR]

Dengue diagnostics have come a long way. Attempts at breaking away from lab-oriented dengue detection, such as NS1 antigen, IgM or IgG antibodies detection have extensively received numerous coverage. As a result, rapid detection tests (RDTs) have started to gain inroads in medical practice. Rapid detection tests notwithstanding, analysis of blood serum is still a relatively complicated task. This includes the necessity of phlebotomy, centrifugation for blood serum, and other reagent-based tests. Therefore, a non-invasive method of dengue detection was considered. In this study, we present the utility of diffuse reflectance skin spectroscopy (bandwidth of 200-2500nm) on the forearm during the triaging period for dengue screening potential. This is performed with multivariate analysis of 240 triaged febrile/suspected dengue patients. The data is then scrutinized for its clinical validity to be included as either confirmed or probable dengue, or a control group. Based on discriminant analysis of several data normalization models, we can predict the patients' clinical dengue-positivity at ranges of accuracy between ~93–98% depending on mode of the data, with a probably optimal sensitivity and specificity to the clinical diagnosis of ~89% and ~100% respectively. From the outcomes of this study, we recommend further trials with cautious optimism. With these findings, it is hoped that the elusive non-invasive detection of tropical diseases may gain platform in the near future. [ABSTRACT FROM AUTHOR]

Background: Dengue is an emerging infectious disease that infects up to 390 million people yearly. The growing demand of dengue diagnostics especially in low-resource settings gave rise to many rapid diagnostic tests (RDT). This study evaluated the accuracy and utility of ViroTrack Dengue Acute - a new biosensors-based dengue NS1 RDT, SD Bioline Dengue Duo NS1/IgM/IgG combo - a commercially available RDT, and SD Dengue NS1 Ag enzyme-linked immunosorbent assay (ELISA), for the diagnosis of acute dengue infection.Methods: This prospective cross-sectional study consecutively recruited 494 patients with suspected dengue from a health clinic in Malaysia. Both RDTs were performed onsite. The evaluated ELISA and reference tests were performed in a virology laboratory. The reference tests comprised of a reverse transcription-polymerase chain reaction and three ELISAs for the detection of dengue NS1 antigen, IgM and IgG antibodies, respectively. The diagnostic performance of evaluated tests was computed using STATA version 12.Results: The sensitivity and specificity of ViroTrack were 62.3% (95%CI 55.6-68.7) and 95.0% (95%CI 91.7-97.3), versus 66.5% (95%CI 60.0-72.6) and 95.4% (95%CI 92.1-97.6) for SD NS1 ELISA, and 52.4% (95%CI 45.7-59.1) and 97.7% (95%CI 95.1-99.2) for NS1 component of SD Bioline, respectively. The combination of the latter with its IgM and IgG components were able to increase test sensitivity to 82.4% (95%CI 76.8-87.1) with corresponding decrease in specificity to 87.4% (95%CI 82.8-91.2). Although a positive test on any of the NS1 assays would increase the probability of dengue to above 90% in a patient, a negative result would only reduce this probability to 23.0-29.3%. In contrast, this probability of false negative diagnosis would be further reduced to 14.7% (95%CI 11.4-18.6) if SD Bioline NS1/IgM/IgG combo was negative.Conclusions: The performance of ViroTrack Dengue Acute was comparable to SD Dengue NS1 Ag ELISA. Addition of serology components to SD Bioline Dengue Duo significantly improved its sensitivity and reduced its false negative rate such that it missed the fewest dengue patients, making it a better point-of-care diagnostic tool. New RDT like ViroTrack Dengue Acute may be a potential alternative to existing RDT if its combination with serology components is proven better in future studies. [ABSTRACT FROM AUTHOR]

This study aims to assess the trends of dengue incidence and socio-demographic characteristics of reported dengue cases in Seremban district, Malaysiaduring the last decade. Secondary dataon reported dengue cases during 2003-2011 were collected fromthe District Health Office, Seremban. Trend analysis was conducted to assess the status of dengue incidence and demographic distribution of the disease in the district. Annual incidence rates of the disease were also calculated and compared. The district experienceda total of 11,936 dengue infections during 2003-2011. It was found that majority of the reported cases were among the Malays (62%), followed by Chinese (17%) and Indians (15%). The age-specific incidence rate was highest in young adult and adult group (15-44 years), followed by middle-age group (45-59 years). The analysis also revealed that majority of the reported cases (on average, 79% per year) came from urban areas of the district which highlights the fact that dengue is still an urban public health problem in Seremban. The study findings provide the critical data and information on trends of dengue incidence andsocio-demographic characteristics of reported dengue cases which might assistthe public health authorities to achieve dengue mortality and morbidity reduction goals in the district. [ABSTRACT FROM AUTHOR]