1.An occurrence of Synthesiomyia nudiseta (Wulp) (Diptera: Muscidae) from a human corpse in a high-rise building in Malaysia: A case report
Syamsa, R.A. ; Ahmad, F.M.S. ; Zuha, R.M. ; Khairul, A.Z. ; Marwi, M.A. ; Shahrom, A.W. ; Omar, B.
Tropical Biomedicine 2012;29(1):107-112
Abstract. This is the first report of Synthesiomyia nudiseta (Wulp) (Diptera: Muscidae) on a
human corpse discovered in a high-rise building in Malaysia. On 5 March 2008, a decomposing
body of an adult female was found on the top floor of a thirteen-story building in Kuala
Lumpur, Malaysia. Her body was colonized by S. nudiseta larvae, which were normally
associated with corpses found indoors at ground level. The post-mortem interval (PMI) was
estimated at approximately 5 to 9 days. This case is significant as it demonstrates that this
species can locate a dead body even in a high-rise building. Further findings of fly distribution
especially in high-rise buildings should be reported to assist entomologists in PMI analysis.
2.Forensic entomology of high-rise buildings in Malaysia: Three case reports
Syamsa, R.A. ; Omar, B. ; Zuha, R.M. ; Faridah, M.N. ; Swarhib, M.S. ; Hidayatulfathi, O. ; Shahrom, A.W.
Tropical Biomedicine 2015;32(2):291-299
The distributions of flies are not only confined to ground level but can also be at
higher altitudes. Here, we report three forensic cases involving dipterans in high-rise buildings
in Kuala Lumpur, Malaysia. Case 1 involved a corpse of adult female found at the top floor of
a fifteen-story apartment. Case 2 dealt with a body of a 75-year-old female discovered in a
bedroom on the eleventh floor of an eighteen-story building, while Case 3 was a 52-year-old
male found in his fifth floor shop house. Interestingly, entomological analysis revealed that all
corpses were infested with similar Dipterans: Megaselia scalaris (Loew) (Diptera: Phoridae),
Synthesiomyia nudiseta (Wulp) (Diptera: Muscidae) and sarcophagid (Diptera:
Sarcophagidae). The first two species were commonly associated with corpses found indoors
at ground level. We noted the additional occurrence of blowflies Chrysomya megacephala
(Fabricius) (Diptera: Calliphoridae) and Chrysomya rufifacies Macquart (Diptera:
Calliphoridae) larvae in Case 2 and Case 3, respectively. Findings from this study are significant
as they demonstrate that certain groups of fly can locate dead bodies even in high-rise
buildings. Forensic entomofauna research on corpses found at high elevation is scarce and
our study has highlighted the peculiarity of the fly species involved in Malaysia.
3.Potential application of Gustatory Receptor 1 (CmegGr1) gene as a molecular marker for identification of Chrysomya megacephala (Diptera: Calliphoridae)
Ghazali, S.N.A. ; Emelia, O. ; Hidayatulfathi, O. ; Syamsa, R.A.
Tropical Biomedicine 2022;39(No.2):226-230
Chrysomya megacephala larvae can easily be identified using cheap traditional microscopy techniques.
Nevertheless, identification using taxonomy keys may be hampered, if the morphological characteristics
of the larvae are incomplete, or immature for microscopic identification. To overcome the difficulty
of species determination, molecular identification has gained relevance and is applied in forensic
investigations. This study aimed to identify a novel target gene, known as the gustatory receptor 1 gene
(CmegGr1), which has never been used for identification. The third instar larvae of Ch. megacephala
(n = 30) and eight other forensically important fly species were obtained from two sources; rabbit
carcasses and the Forensic Entomology Unit collection. Their DNAs were extracted and the CmegGr1
gene was amplified using polymerase chain reaction (PCR). The resulting sequences were subjected
to phylogenetic analysis. A 209 bp fragment of the CmegGr1 gene was successfully amplified in 80%
(24/30) of Ch. megacephala samples, while all of the non-Ch. megacephala species were not amplified.
The phylogenetic analysis revealed that the evolutionary tree of CmegGr1 shares many traits with the
21a gustatory receptors of Calliphora stygia and Lucilia cuprina (Gr21a), which are also classified as
necrophagous fly species. The high specificity of species identification was demonstrated in the present
study using DNA barcoding, which led to the conclusion that the CmegGr1 gene could serve as an
alternative marker for identifying Ch. megacephala.
4.A comparison of different types of ovitraps for outdoor monitoring of Aedes mosquitoes in Kuala Lumpur
Ahmad-Azri, M. ; Syamsa, R.A. ; Ahmad-Firdaus, M.S. ; Aishah-Hani, A.
Tropical Biomedicine 2019;36(2):335-347
Dengue is a significant public health problem in Malaysia and vector surveillance
is one of the important components in a vector control program. Routinely vector
surveillance in Malaysia is performed through larval surveys. However, larval surveys
have several limitations. Thus ovitraps are used as an alternative method for monitoring
dengue vectors. The aim of this study was to determine the effectiveness of Standard
Ovitrap (SO), Mosquito larvae Trapping Device (MLTD), Double Sticky Ovitrap (DST) and
NPK Fertiliser Trap to monitor the abundance of Aedes mosquitoes. Each ovitrap was
placed at four different sampling points and rotated to the next position every one week.
Larvae and adult mosquitoes were collected and identified in the laboratory. All four
trapping methods successfully collected larvae of Aedes mosquitoes. The mean number of
larvae per ovitrap in DST was significantly higher (p < 0.05) compared to SO and MLTD.
DST and NPK Fertiliser Trap were capable of capturing adult mosquitoes. Ovitrap Index
and the mean number of adults per ovitrap in NPK Fertiliser trap were significantly higher
(p < 0.05) as compared to DST. Another set of experiments were conducted to compare
NPK Fertiliser traps containing fresh NPK fertiliser solution with those containing stock
NPK Fertiliser solution. The fresh solution was prepared fresh while the stock solution was
stored for a month before being used in the field. Result shows no significant differences
(p > 0.05) between these solutions. Findings from this study conclude that DST is the most
effective ovitrap to monitor Aedes larvae, while NPK Fertiliser trap is the most effective
ovitrap to trap Aedes adult mosquitoes in the study area.
5.Acaricidal activity of the essential oils from Citrus hystrix (Rutaceae) and Cymbopogon citratus (Poaceae) on the cattle tick Rhipicephalus (Boophilus) microplus larvae (Acari: Ixodidae)
Shezryna, S. ; Anisah, N. ; Saleh, I. ; Syamsa, R.A.
Tropical Biomedicine 2020;37(No.2):433-442
Rhipicephalus (Boophilus) microplus serves as an important ectoparasite of livestock and a vector of several pathogens resulting in diseases, subsequently affecting the agricultural field as well as the economy. The extensive use of synthetic acaricides is known to cause resistance over time and therefore a much safer, effective and environmentally friendly alternative to overcome tick infestation should be implemented. Larval immersion tests (LIT) were done to evaluate the effects of Citrus hystrix (Family: Rutaceae) and Cymbopogon citratus (Family: Poaceae) essential oils (EOs) for their individual and combined (1:1) acaricidal activity against the cattle tick. Results showed that LC50 and LC90 values in 24 and 48 hours for Cit. hystrix EO were 11.98% and 24.84%, and 10.95% and 21.71% respectively. LC50 and LC90 values for Cym. citratus EO were 1.21% and 6.28%, and 1.05% and 6.12% respectively. The mixture of EOs from two plants in 1:1 ratio (Cit. hystrix 50%: Cym. citratus 50%) was found to exhibit antagonistic effect (synergistic factor < 1). The 24 hours and 48 hours LC50 and LC90 values for combined EOs were 1.52% and 2.84%, and 1.50% and 2.76% respectively. Individual and combined essential oils were subjected to qualitative analysis using gas chromatography-mass spectrometry (GC-MS) to screen the chemical components present in EOs. Our results showed that the combination of Cit. hystrix and Cym. citratus at 1:1 ratio resulted in an antagonistic effect and the use of Cym. citratus alone is more toxic to R. (B.) microplus, making it a better alternative to chemical based acaricide.