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Start Over Publication Year Range Last 10 years Region kuala lumpur (malaysia) Region malaysia Publisher elsevier b.v.
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1. Dengue epidemiological characteristic in Kuala Lumpur and Selangor, Malaysia.

Author

Tay, Chai Jian, Fakhruddin, Muhammad, Fauzi, Ilham Saiful, Teh, Su Yean, Syamsuddin, Muhammad, Nuraini, Nuning, and Soewono, Edy

Subjects
*ARBOVIRUS diseases, *DENGUE, *MOSQUITO vectors, *MOSQUITO control, *PREDICTIVE tests, *SENSITIVITY analysis, *TEST methods
Abstract

In the last few decades, dengue remains a leading public health problem in Malaysia. The problem persists with increasing trend of cases despite implementation of various interventions by the Ministry of Health Malaysia. The difficulty in eradicating dengue disease throughout the world is related to the complexity of the dengue phenomena. With no access to a safe, effective and affordable dengue vaccine, the only intervention strategy is to control the mosquito vector. In reality, data on mosquitoes is limited, and in most cases, the dynamic of mosquito is unobservable. In this study, based on the dengue incidence data in Malaysia − Kuala Lumpur and Selangor − from the year 2011 to 2014, a transmission model of type SI-SIR is constructed. Transmission rates in the two locations are estimated from the data fitting of the dynamic of infected human to dengue incidence. The average infection rate and the estimated average reproduction number for Selangor are estimated to be 0.1674 week−1 and 1.025, respectively. An enclave in Selangor, the capital city Kuala Lumpur has slightly lower average dengue infection rate of 0.1656 week−1 and estimated average reproduction number of 1.014. Further sensitivity analysis indicated that the dengue infection rate is the critical parameter of dengue transmission in Kuala Lumpur and Selangor. This implies that dengue control strategies should focus on reducing the dengue infection rate. Numerical simulations are also performed to validate the estimated dengue infection rate, to illustrate the dengue dynamics and to determine the effects of dengue control strategies in the two selected locations. The predictive test results of this method also provide good results in capturing the pattern of dengue cases both in Kuala Lumpur and in Selangor. Numerical simulations on instantaneous reproduction number reveal that the instantaneous reproduction number of Kuala Lumpur varies between 0.8 and 1.28 while the instantaneous reproduction number of Selangor varies between 0.7 and 1.2. The insights and results presented in this paper are useful to the relevant authorities in analyzing the effect of mosquito intervention for reducing the prevalence of dengue in Malaysia. [ABSTRACT FROM AUTHOR]

Published
2022
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2. Analysis of lightning flash rate with the occurrence of flash floods and hailstorms in Peninsular Malaysia.

Author

Bahari, Noraishah, Mohammad, Sulaiman Ali, Mohd Esa, Mona Riza, Ahmad, Mohd Riduan, Ahmad, Noor Azlinda, and Malek, Zulkurnain Abdul

Subjects
*HAILSTORMS, *THUNDERSTORMS, *RADAR meteorology, *LIGHTNING, *FLOODS, *RAINFALL, *STORMS
Abstract

This paper will present five flash flood cases in Johor and two hailstorms from Kuala Lumpur and Melaka reported during lightning activities to determine the relationship between lightning flash rate and rainfall that occurred from 2013 to 2017. The flash floods were observed based on lightning data obtained from Tenaga Nasional Berhad Research Sdn. Bhd. (TNBR) and rainfall data from the Department of Irrigation and Drainage (DID). On the other hand, storm-producing hails were observed based on the lightning flash rate using electromagnetic field measurements and weather radar for their reflectivity value and cloud structure. The detection of a lightning flash, especially the negative narrow bipolar event (−NBE) and positive cloud-to-ground (+CG), could be a possible indicator of a deeper convective storm that could lead to the production of hails. In the 24-h observation of selected days when a flash flood occurred, lightning strikes correlation with rainfall had r-values ranging from 0.6 to 0.9, where the lightning data may enhance flood forecasting accuracy when combined with rainfall. Meanwhile, during the first hailstorms in Kuala Lumpur, the highest −NBEs flash rate detected during the hails appeared where 16 −NBEs were detected in a span of 5 min with reflectivity value between 53 and 55 dBz and cloud top height of 20 km. During the second hailstorms in Melaka, more + CG flashes rather than −NBE were detected during the appearance of the hail, with 64 +CG flashes and five −NBEs with reflectivity values between 60 and 66 dBz and cloud top height of 18.8 km. Based on the high convective strength, cloud top height, and presence of hailstones, −NBE and +CG flash could be possible indicators of storm severity, especially in Malaysia. • Relationship between lightning events and the severity of convective thunderstorms • The severity of the thunderstorm may not be visible at its earlier stage until the damages occurred • In Malaysia, a severe thunderstorm is not frequently studied as in temperate regions because this phenomenon is unusually formally reported • Investigating the relationship between the occurrence of severe convection with a lightning detection system, the severity of convective thunderstorms may be detected earlier with the pronounced lightning activities and selected flashes trend • Hailstorms and heavy rainfall lead to flash floods are one of the outcomes of the severity of these thunderstorms [ABSTRACT FROM AUTHOR]

Published
2023
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