Environmental Assessment and Infestation Level of the Dengue Vectors at Residential Area in Puncak Alam, Selangor
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Journal of Sustainability Science and Management eISSN: 2672-7226 Volume 16 Number 1, January 2021: 120-128 © Penerbit UMT ENVIRONMENTAL ASSESSMENT AND INFESTATION LEVEL OF THE DENGUE VECTORS AT RESIDENTIAL AREA IN PUNCAK ALAM, SELANGOR FATIN AZURA1, NAZRI CHE DOM*1,2 AND SITI NAZRINA CAMALXAMAN1,2 1Centre of Environmental Health & Safety, 2Integrated Mosquito Research Group (IMeRGe), Faculty of Health Sciences, Universiti Teknologi MARA, 42300 Puncak Alam, Selangor, Malaysia. *Corresponding author: [email protected] Submitted final draft: 21 May 2020 Accepted: 3 June 2020 http://doi.org/10.46754/jssm.2021.01.011 Abstract: The control of mosquitoes in residential areas calls for in-depth knowledge of the breeding habits of the mosquitoes, especially Aedes aegypti and Aedes albopictus. Therefore, this study aims to assess the environmental condition and infestation level of Aedes vectors at selected residential areas in Puncak Alam, Selangor. The aims of this study are to understand the environmental profile of residential areas towards infestation level of dengue vectors. A pilot study was conducted in Puncak Alam in order to understand the infestation profile of dengue vectors in residential areas by assessing the environmental condition index (ECI) in front and yard area of residential area. In this study, a minimum of a hundred houses in each residential area was observed for the environmental condition of front and yard of the premises. Concurrently, a total of thirty ovitraps were placed randomly at outdoor premises in order to measure the infestation level of the Aedes mosquitoes. A total of 318 households were inspected in both front area (FA) and yard area (YA) where in general, the environmental condition in front of houses is better than the yard area. The same pattern was also observed in which the infestation level of Aedes mosquito population in FA and YA ranged from 15.40 – 35.25 and 11.88 – 47.91, respectively. In conclusion, environmental conditions play a main role in the distribution of dengue vector. Keywords: Residential area, environmental condition, infestation level, Aedes. Introduction (Sarfraz et al., 2012) and brackish waters Urbanisation is a factor that can increase the (Idris et al., 2013; Ramasamy et al., 2011). number of preferred habitats for Aedes mosquito The presence of vegetation condition between thus increasing the density and survival of Aedes community area and mosquito breeding site mosquito especially in a residential area (Saleeza provides a disposal route for biting insect to et al., 2011). Another factor that contributes community areas. According to Kesetyaningsih in dengue transmission and distribution is et al., (2016) the mosquito survival was environmental parameters. This parameter can affected by humidity that is maintained by the cause changes in dengue transmission that is presence of vegetation. Next, human ecology is related to the host, such as the demographic responsible for the creation of a mosquito genic pattern. Furthermore, the land use such as housing environment. Generally, residential area is a type, soil moisture and greenness can contribute potential source for the existence of breeding to the epidemic of dengue transmission (Aziz et sites due to environment condition, either indoor al., 2011). or outdoor area. Community areas, particularly residential Vector surveillance can be used to determine areas, are located in close proximity to major changes in the distribution and vector density mosquito habitats. Previous entomological and to obtain relative control measurement studies showed that dengue vectors have been of the vector population. It also can serve to captured in vegetated areas (Hayden et al., 2010; identify high-density infestation study area and Vezzani et al., 2005), rubber plantations (Paily selection of sampling method depending on et al., 2013; Sumodan, 2003), marshy swamps the vector surveillance objective. Thus, several ENVIRONMENTAL ASSESSMENT AND INFESTATION LEVEL OF THE DENGUE VECTORS 121 indices have been described as vector population eggs laid in their habitat. Therefore, this study monitor for dengue transmission. There are was aimed to assess the environmental condition three approaches of dengue measures commonly and infestation level of Aedes vectors at selected used in Aedes surveillance in residential areas residential areas in Puncak Alam, Selangor. namely: (i) premise condition index (Roberto et al., 2013; Parasuraman et al., 2012a) (ii) ovitrap Materials and Methods surveillance (Rozilawati et al., 2007 and Ligia et al., 2013) and (iii) integrating both approaches Study Site and Study Population (Roberto et al., 2013 and Leticia et al., 2005). Puncak Alam is the main township development Premise condition index (PCI) value score in the Kuala Selangor District, State of Selangor, indicates a simple index incorporating predictor Malaysia and has been selected as the case of the mosquito breeding (house condition, study area. Kuala Selangor District is one of yard tidiness and degree of shade) that does not the less urbanised districts in Selangor. It is require indoor inspection of the premises (Tun- located approximately 20 kilometres in the Lin et al., 1995). However, vulnerability of the northwest direction from Shah Alam, the state PCI includes inability of the inspector to observe capital of Selangor. Puncak Alam development many rear yards’ condition and the risk of seeing started in the late 90’s under the management inconsistent PCI scoring between different of Bukit Cherakah Development Sdn Bhd inspectors (Parasuraman & Radhakrishnan with approximately 57km2 in size. Currently, 2012b). Review conducted by from Ligia et most of the developments in Puncak Alam al., (2013) showed that mosquito behaviour are housing area with a small percentage of is the main factor in the disease epidemiology commercial and industrial units. As a sub-urban transmitted by mosquitoes. Therefore, the area, Puncak Alam is surrounded by rural lands ovitrap acts as an effective tool for providing within the boundary of Kuala Selangor district. spatial and temporal data in dengue control Puncak Alam was selected due to its population measures. In general, most of the surveillance distribution with a variety of new residential studies, either the epidemiological evidence or areas and has a significant public health quantitative methods were used for assessing the implication in relation to control and prevention dengue transmission. of dengue outbreak. Ovitrap surveillance was used as a sampling technique to detect and measure the Study Design density of mosquito population by measuring A minimum of 318 houses in selected the positive ovitrap index (POI) (Ligia et al., residential areas in Puncak Alam was inspected 2013; Wan Norafikah et al., 2009; Rozilawati in each zone (A, B and C). Within the selected et al., 2007). POI is a percentage of Aedes residential area 30 houses chosen randomly/ positive ovitrap divided by number of ovitraps zones were used to observe the condition of the collected from the study (Wan Norafikah et environment and to measure the infestation of al., 2009). Prevention and control measures Aedes vectors, using ovitrap. The front and back of the dengue disease are dependent on vector yards of the premises were used to evaluate the surveillance and control measures by integrating environmental condition of the residential areas both approaches of ovitrap surveillance and using the criteria that contribute to the existence the environmental condition index (ECI) as an of mosquito activities which include house indicator of mosquito infestation that could be maintenance, solid waste management, degree used to relate between ECI and infestation to of shade and drainage facilities. Then each determine the density of mosquito population premise was scored from lower to the highest (Roberto et al., 2013). The ovitrap has been according to the method developed by Tun-Lin used as a proxy to measure a number of adult et al., (1995). At the same time, the ovitraps mosquitoes present from the total number of were placed randomly at outdoor premises in a Journal of Sustainability Science and Management Volume 16 Number 1, January 2021: 120-128 Fatin Azura et al. 122 shaded area in order to measure the infestation As for scoring of the environmental of Aedes vectors. After consecutive days of condition index (ECI), the house was classified exposure, the ovitraps were recollected and then into three classes. Score 1 = well maintained were brought to the laboratory for egg count and house (structure in good condition, new paint, species identification (Hasnan et al., 2017). place is visibly clean and well maintained), Score 2 = reasonably well maintained (poor or Environmental Condition Assessment simple structure, but well organised and clean) and Score 3 = poorly maintained (poor structure, The purpose of this assessment is to evaluate peeling walls, broken or improvised items, little the environmental condition including drainage organisation or cleanliness). Yard classified facilities and solid waste management. The as Score 1 = well maintained (organised, no poorly built and improperly managed drainage apparent waste or scrap, grass is short, yard system can contribute to the high mosquito well maintained), Score 2 = reasonably well infestation. For instance, the clogged drains maintained (moderately well-kept or poor with clear stagnant water are considered good structure, but well organised and clean) and artificial container