Hamdan Ahmad

Hamdan Ahmad
Universiti Sains Malaysia | USM · School of Biological Sciences

About

75
Publications
32,825
Reads
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636
Citations
Additional affiliations
September 2014 - present
Universiti Sains Malaysia
Position
  • Lecturer
May 2010 - present
Vector Control Research Unit, USM, Malaysia
Position
  • Coordinator

Publications

Publications (75)
Article
Full-text available
Conventional methods to study insect taxonomy especially forensic and medical dipterous flies are often tedious, time-consuming, labor-intensive, and expensive. An automated recognition system with image processing and computer vision provides an excellent solution to assist the process of insect identification. However, to the best of our knowledg...
Article
Full-text available
This paper introduces a new mosquito images dataset that is suitable for training and evaluating a recognition system on mosquitoes in normal or smashed conditions. The images dataset served mainly for the development a machine learning model that can recognize the mosquito in the public community, which commonly found in the smashed/damaged form b...
Article
Background: Public community engagement is crucial for mosquito surveillance programs. To support community participation, one of the approaches is assisting the public in recognizing the mosquitoes that carry pathogens. Therefore, this study aims to build an automatic recognition system to identify mosquitos at the public community level. We cons...
Article
Background The application of computer vision and deep learning to pest monitoring has recently received much attention. Although several studies have demonstrated the application of object detection to the number of pests on a substrate, for house flies (Musca domestica L.), in which the larvae were aggregated and overlapped together, the object d...
Article
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Classification of Aedes aegypti (Linnaeus) and Aedes albopictus (Skuse) by humans remains challenging. We proposed a highly accessible method to develop a deep learning (DL) model and implement the model for mosquito image classification by using hardware that could regulate the development process. In particular, we constructed a dataset with 4120...
Preprint
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Larviciding is an effective control method in managing mosquito-borne diseases. However, current carrier materials used in larvicides formulation raised environmental concerns due to its non-renewable origin. Herein, our study aimed to evaluate the application of the renewable source kenaf cellulose nanofiber (KCNF) impregnated with temephos for th...
Article
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We aim to investigate the effect of large-scale human movement restrictions during the COVID-19 lockdown on both the dengue transmission and vector occurrences. This study compared the weekly dengue incidences during the period of lockdown to the previous years (2015 to 2019) and a Seasonal Autoregressive Integrated Moving Average (SARIMA) model th...
Article
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Gastrointestinal nematode infections can cause great losses in revenue due to decrease livestock production and animal death. The use of anthelmintic to control gastrointestinal nematode put a selection pressure on nematode populations which led to emergence of anthelmintic resistance. Because of that, this study was carried out to investigate the...
Article
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The incidence of infestation by a black stink bug Coptosoma variegatum (Hemiptera: Plataspidae) on mango Mangifera indica L. (Anacardiaceae) tree was scientifically reported for the first time in Malaysia. This insect is commonly known as home invader and legume pest. Abundance of this insect was monitored on mango panicles by 15 minutes hourly col...
Preprint
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The impact of movement restrictions during the COVID-19 lockdown on the existing endemic infectious disease dengue fever has generated considerable research interest. We compared the Malaysia weekly epidemiological records of dengue incidences during the period of lockdown to the trend of previous years (2015 to 2019) and a simulation at the corres...
Article
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The development of ecotourism in Penang has to acquire environmental knowledge. We aimed to determine the supply, demand and career pathway for the environmental program in Penang. All the programs of Higher Education Providers (HEPs) were analyzed, market demand was conducted on the high schools' students of Penang empirically, and the career path...
Article
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This study investigated the diet of introduced barn owls (Tyto alba javanica, Gmelin) in the urban area of the Main Campus of Universiti Sains Malaysia, Penang, Malaysia, based on collected regurgitated pellets. We also compared the diet of the introduced barn owls with the diet of barn owls from two agricultural areas, i.e. oil palm plantations an...
Article
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A major current focus in agricultural soil conservation is to ensure a pest control program is sustainable, and therefore, entomopathogenic fungi have been considered and extensively studied as biopesticides. However, the ecological role of entomopathogenic fungi in degrading insecticides in soil is not well understood. In this study, the potential...
Article
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An infestation of a snout weevil Alcidodes sp. (Coleoptera: Curculionidae) on Mangifera indica L. (Anacardiaceae) was scientifically reported for the first time in Malaysia. This snout weevil causes severe damage on young stems and flower panicles. Even though the tree survived from a few infestations, but severe cases could pose a serious economic...
Article
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An investigation was undertaken for screening and isolating nematophagous-fungi from the faecal samples of various grazing animals and soils in Malaysia. Total of 111 faeces and 50 soil samples were collected and the samples were cultured on 2% water agar plates. The growth of nematophagous-fungi was stimulated by sprinkling-baiting technique. The...
Preprint
Full-text available
This study investigated the diet of introduced barn owls (Tyto alba javanica, Gmelin) in the urban area of the Main Campus of Universiti Sains Malaysia, Penang, Malaysia, based on collected regurgitated pellets. We also compared the diet of introduced urban barn owls with the diet of barn owls from two agricultural areas, i.e. oil palm plantations...
Article
Full-text available
Megaselia scalaris (Loew) is one of the best-known diets for the swiftlet. Previous studies have addressed the problem of some mass rearing conditions for this insect; unfortunately, the details of the nutritional composition of the life stages and cost of the breeding materials were insufficiently reported, even though this information is crucial...
Article
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Background: The frequency and magnitude of dengue epidemics continue to increase exponentially in Malaysia, with a shift in the age range predominance toward adults and an expansion to rural areas. Despite this, information pertaining to the extent of transmission of dengue virus (DENV) in the rural community is lacking. This community-based pilot...
Article
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Background & objectives: In sterile insect technology (SIT), mating competitiveness is a pre-condition for the reduction of target pest populations and a crucial parameter for judging efficacy. Still, current SIT trials are being hindered by decreased effectiveness due to reduced sexual performance of released males. Here, we explored the possible...
Article
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Megaselia scalaris (Loew) (Diptera: Phoridae) provides great evidential value in estimating the postmortem interval (PMI) compared with other dipterans due to its common occurrence on human corpses both indoors and in concealed environments. Studies have focused on the effect of temperature, larval diet, and photoperiod on the development of the sp...
Article
This study was conducted to isolate and identify lactobacilli from larval and adult midgut of wild Aedes aegypti (Ae. aegypti) to find candidate bacteria for paratransgenic control. Characterization of the bacterial symbionts was done using Gram staining, motility test, catalase test, and biochemical tests, among others, and the morphological featu...
Article
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The oriental fruit fly, Bactrocera dorsalis Hendel, is one of the most problematic tephritid fruit flies and an agriculturally-important pest due to the severe damages caused in commercial fruits such as mango (Mangifera indica L.). The species is known to be able to develop eggs in different stage of ripening fruits. Therefore, this study is aimed...
Article
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Yearly, huge amounts of sock refuse are discarded into the environment. Socks contain many molecules, and worn ones, which are rich in smell-causing bacteria, have a strong influence on animals’ behaviors But, the impacts of sock odor on the oviposition behavior of dengue vectors is unknown. We assessed whether Aedes albopictus changes its oviposit...
Article
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Insecticide-based vector control approaches are facing challenges due to the development of resistance in vector mosquitoes. Therefore, a proper resistance surveillance program using baseline lethal concentrations is crucial for resistance management strategies. Currently, the World Health Organization's (WHO) diagnostic doses established for Aedes...
Article
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A survey was carried out in mango orchards the infestation levels of fruit fly indica L.) through damaged fruit fruits: Bactrocera dorsalis Bactrocera dorsalis was recorded carambolae (9%). The highest fruit infestation pupae/kg), followed by Bukit Changgang (36.08±8.35 pupae/k ±4.86 pupae/kg) whilst Jitra showed the lowest A survey was carried out...
Article
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In this study, bifenthrin (Maxxthor SC, Ensystex Australasia Pty Ltd), imidacloprid (ProthorSC, Ensystex Australasia Pty Ltd) and fipronil (Regent®50SC, Bayer) were applied on the natural infest manures according to the manufacturer rate during a broiler breeding cycle. Solvent directimmersion extraction (SDIE) was used in detecting the target comp...
Article
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The potential of integrating the mycoinsecticide, Metarhizium anisopliae (Met.), into house fly control programs is tremendous. However, the interaction between the fungus and insecticide, when applied at poultry farms, remains poorly understood. This study investigated the interaction between M. anisopliae and two selected insecticides, cyromazine...
Article
Full-text available
In dengue mosquitoes, successful embryonic development and long lifespan are key determinants for the persistence of both virus and vector. Therefore, targeting the egg stage and vector lifespan would be expected to have greater impacts than larvicides or adulticides, both strategies that have lost effectiveness due to the development of resistance...
Article
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In nature, adult mosquitoes typically utilize nectar as their main energy source, but they can switch to other as yet unidentified sugary fluids. Contemporary lifestyles, with their associated unwillingness to consume leftovers and improper disposal of waste, have resulted in the disposal of huge amounts of waste into the environment. Such refuse o...
Article
In nature, adult mosquitoes typically utilize nectar as their main energy source, but they can switch to other as yet unidentified sugary fluids. Contemporary lifestyles, with their associated unwillingness to consume leftovers and improper disposal of waste, have resulted in the disposal of huge amounts of waste into the environment. Such refuse o...
Article
Full-text available
Background Globally, dengue infections constitute a significant public health burden. In recent decades, Malaysia has become a dengue hyper-endemic country with the co-circulation of the four dengue virus serotypes. The cyclical dominance of sub-types contributes to a pattern of major outbreaks. The consequences can be observed in the rising incide...
Article
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Body size is a physical factor of crucial importance underlying important traits of the reproductive dynamics of both sexes in mosquitoes. Most studies on the influence of body size in mating success of dengue vectors addressed sperm transfer to females and did not consider egg production, a prerequisite for population maintenance; male body size i...
Article
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Objectives: To determine abundance, distribution and diversity of potential breeding container habitats of the dengue vectors in public places of schools, restaurants, mosques and parks in Southwest areas of Penang Island, Malaysia. Methods: Premises at restaurants, schools, parks and mosques were surveyed simultaneously and visually inspected for...
Article
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Dengue vector control still heavily relies on the use of chemical insecticides, and the widespread use of insecticides has led to resistance in mosquitoes. The diagnostic dose is a key part of resistance monitoring. The present study corroborates the discriminating lethal doses of temephos and malathion based on dose-response of known susceptible s...
Article
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Determining the control threshold for a pest is common prior to initiating a pest control program; however, previous studies related to the house fly control threshold for a poultry farm are insufficient for determining such a threshold. This study aimed to predict the population changes of house fly population by comparing the intrinsic rate of in...
Article
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Dengue mosquitoes are evolving into a broader global public health menace, with relentless outbreaks and the rise in number of Zika virus disease cases as reminders of the continued hazard associated with Aedes vectors. The use of chemical insecticides-the principal strategy against mosquito vectors-has been greatly impeded due to the development o...
Article
Dengue mosquitoes are evolving into a broader global public health menace, with relentless outbreaks and the rise in number of Zika virus disease cases as reminders of the continued hazard associated with Aedes vectors. The use of chemical insecticides—the principal strategy against mosquito vectors—has been greatly impeded due to the development o...
Article
Full-text available
It is crucial to understand the degradation pattern of insecticides when designing a sustainable control program for the house fly, Musca domestica (L.), on poultry farms. The aim of this study was to determine the half-life and degradation rates of cyromazine, chlorpyrifos, and cypermethrin by spiking these insecticides into poultrymanure, and the...
Article
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Ants are social insects that are commonly found in tropical ecosystems and have adapted well to the urban environment. They are among the most prevalent pests in households. This study demonstrates the abundance and prevalence of structure infesting ants in residential buildings in Penang Island, Malaysia. Three locations situated in urban, suburba...
Article
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Introduction: Dengue virus (DENV) is principally transmitted by the Aedes aegypti mosquito. To date, mosquito population control remains the key strategy for reducing the continuing spread of DENV. The focus on the development of new vector control strategies through an understanding of the mosquito-virus relationship is essential, especially targ...
Article
Full-text available
Mating behavior between Aedes aegypti and Ae. albopictus, established colony strains were examined under laboratory conditions (30-cm(3) screened cages) for 5 consecutive days. The effect of selected male densities (30, 20, 10) and female density (20) on the number of swarming, mating pairs, eggs produced, and inseminated females were evaluated. Ma...
Conference Paper
Full-text available
Termites are pests that makes woody material as a primary food source. However, not all termites are classified as pests as there are species of termites are important in maintaining the environmental balance. Therefore, termite technician school program was conducted to share and deliver the knowledge from termite research findings with pest contr...
Article
Full-text available
In this study, the toxicology of two commercial larvicides-cyromazine (Neporex 50SP) and ChCy (combination of chlorpyrifos and cypermethrin, Naga 505)-and five commercial adulticides-thiamethoxam (Agita 10WG), cyfluthrin (Responsar WP), lambda-cyhalothrin (Icon 2.8EC), fipronil (Regent 50SC), and imidacloprid (Toxilat 10WP)-was examined against the...
Conference Paper
Full-text available
In this study, bifenthrin, imidacloprid and fipronil were applied on the natural infest manures according to the manufacturer rate during a broiler breeding cycle. Two extraction methods were prior studied for their suitability and sensitivity in detecting the target compound and later, quantification and qualification of the insecticides in field...
Article
Full-text available
Measuring wild pollinator services in agricultural production is very important in the context of sustainable management. In this study, we estimated the contribution of native pollinators to mango fruit set production of two mango cultivars Mangifera indica (L). cv. 'Sala' and 'Chok Anan'. Visitation rates of pollinators on mango flowers and numbe...
Article
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The sector of livestock and aquaculture are growing rapidly in order to meet the incremental demand of essential protein for the world's population. However, the supply of plant-based animal feed was limited by resources such as land and water. The opportunity for insect as the substitute to animal feed is tremendous; nonetheless, little attention...
Article
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The magnitude of dengue transmission depends largely on the level of human–vector contact. Therefore, knowledge regarding the biting periodicity of mosquitoes is crucial to determine transmission periods' risk, and in planning personal protection measures. Dengue vectors are day-active and endure transitory periods of starvation overnight. However,...
Article
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A study was conducted on 16 commercial free range chickens (8 males and 8 females) sourced from Alor Setar, Kedah in order to determine the prevalence of ecto and endoparasites. Results showed that there were 12 different species of ecto-and endoparasites from these chickens. Four (4) species of ectoparasites which consist of three lice and a tick...
Article
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Dengue is a prevalent arboviral disease and the development of insecticide resistance among its vectors impedes endeavors to control it. Coffee is drunk by millions of people daily worldwide, which is associated with the discarding of large amounts of waste. Coffee and its waste contain large amounts of chemicals many of which are highly toxic and...
Article
Full-text available
Aedes aegypti is a principal vector responsible for the transmission of dengue viruses (DENV). To date, vector control remains the key option for dengue disease management. To develop new vector control strategies, a more comprehensive understanding of the biological interactions between DENV and Ae. aegypti is required. In this study, a cDNA libra...
Conference Paper
A degradation study of three commercial termiticides concentration was carried out at Universiti Sains Malaysia main campus. Type of soil used in the soil-termiticides treatment was sandy loam soil. Soil-termiticides treatment was done at rate of 0.25% active ingredient. Degradation study of termiticides in soil was done using ultra performance liq...
Article
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Due to problems with chemical control, there is increasing interest in the use of microsporidia for control of lepidopteran pests. However, there have been few studies to evaluate the susceptibility of exotic species to microsporidia from indigenous Lepidoptera. We investigated some biological characteristics of the microsporidian parasite isolated...