Relationship between Demodex sp. Infestation and Acne Problem among Adults in Klang Valley, Malaysia / Jurnal Sains Kesihatan Malaysia

Demodex sp. is a skin ectoparasite known as follicle mite. The objectives of this study were to determine the prevalence of Demodex sp. infestation among Malaysian adults with age ranges from 20 to 29 years old in Lembah Klang and to determine the relationship between the infestation status and gender and acne problem on face. This is the first study that has been conducted in Malaysia to determine the prevalence of Demodex sp. infestation. A total of 350 people participated in this study. Samples were selected by stratified random sampling. Skin scraping was carried out on forehead, nose, cheeks and chin. All specimens were mounted in Hoyer’s medium and studied under light microscope. Questionnaires were distributed to the subjects to identify acne problem on their skin conditions. The overall prevalence of Demodex sp. infestation was 18.9% with higher prevalence in males (25.7%) compared to females (12.0%). There was no significant difference between acne problem and Demodex sp. infestation. In conclusion, infestation of Demodex sp. was detected in a fifth of the subjects, with men had more problems.

Effects of Temperatures on Larval Development of Chrysomya megacephala (Fabricius) and Chrysomya rufifacies (Macquart) (Diptera: Calliphoridae): Application in Forensic Science / Jurnal Sains Kesihatan Malaysia

Chrysomya megacephala (Fabricius) and Chrysomya rufifacies (Macquart) are two important species of blow flies that could be utilised as indicators to estimate the Post Mortem Interval (PMI) of corpses in forensic science. Determination of PMI of corpses is based on the larva size and its development stages. Development studies of eggs, larvae and pupae of Ch. megacephala and Ch. rufifacies at 27ºC, 30ºC and 33ºC were carried out using an insect growth chamber. Data from these studies were used to construct growth curves and Accumulated Degree Hours (ADH) for both species. Ch. megacephala needs 9.15 days to complete one life cycle at 27ºC, 8.54 days at 30ºC and 6.76 days at 33ºC. Development for Ch. rufifacies is slower than Ch. megacephala and takes 9.92 day at 27ºC, 9.13 days at 30ºC and 7.44 days at 33ºC. Eggs of the two species hatch faster at 33ºC compared to the two other temperatures. Low value of ADH shows shorter life cycle of that particular species. This study’s findings are useful in estimating PMI of the corpses found under various environmental temperatures.