A cross-sectional study was conducted in February 2006 to determine the prevalence of Trichuris trichiura infection among Orang Asli (Aborigine) children at Pos Lenjang, Pahang. A total of 71 faecal samples were collected from the children (40 girls and 31 boys) aged between 1-12 years. The samples were examined for the presence of Trichuris trichiura ova using direct smear and formalin-ether concentration techniques. The result revealed that the overall prevalence of Trichuris trichiura infection was 43.7%. The infection was higher in males (51.6%) compared to females (37.5%), though not statistically significant (p > 0.05). According to age group, the school-aged children had higher prevalence of infection (56.8%) than preschool children (29.4%) (p < 0.05). Low socioeconomic status, large family size, poor environmental sanitation and poor personal hygiene are possible contributing factors that increase the prevalence of infection among the Orang Asli children at Pos Lenjang. In 31 samples positive for Trichuris trichiura, a detection rate of 100% was obtained using formalin-ether concentration, compared to 25.8% with direct smear technique. Thus, it is recommended that both techniques be performed in routine faecal examination for a more accurate diagnosis.

Entamoeba histolytica infection is widespread worldwide and higher prevalence is usually seen among the indigenous under priviledged people living in the tropics and subtropics. Seventy one Orang Asli children from Pos Lenjang, Pahang participated in this study and were grouped according to age and gender. Faecal samples were collected and examined for the presence of Entamoeba histolytica using 3 different diagnostic techniques namely the direct faecal smear, formalin ether concentration and trichrome staining.The prevalence of Entamoeba histolytica infection among the Orang Asli children at Pos Lenjang, Pahang was high at 22.5%. According to gender, female children showed higher prevalence (32.5%) compared to male at only 9.7%. Infection was also apparently higher among the school going children at 32.4% compared to preschool children (11.8%). The high prevalence of Entamoeba histolytica infection amongst the Orang Asli children at Pos Lenjang is related to several factors including low socioeconomic status, lack of basic amenities, culture, and poor knowledge on healthy life practice.

Giardia intestinalis is a cosmopolitan parasite and the infection is widely distributed worldwide especially in the developing countries with poor sanitation and lack of potable water. Seventy one Orang Asli children from Pos Lenjang, Pahang participated in this study and stool specimens were collected and examined for G. intestinalis using three diagnostic techniques ie; Direct fecal smear, Formalin-ether concentration and Trichrome staining. The prevalence of G. intestinalis infection among the Orang Asli children in Pos Lenjang, Pahang was as high as 43.7%. According to gender, the prevalence was almost similar between the female and male children with 45.0% and 41.9%, respectively. The infection was more prevalent in school going children (48.6%) as compared to the pre-school children (38.2%).

Acanthamoeba is a free living protozoa that can cause keratitis and granulomatous amoebic encephalitis. Physiological characteristics of this amoeba are found to have a medical importance in which it can be related to the pathogenicity potential of the organism. This study was carried out to investigate the physiological characteristics of survivability during axenization. Six Acanthamoeba strains from three clinical isolates (HSB 1, HKL 48 and HKL 95) and three environmental isolates (PHS 2, PHS 11 and PHS 15) were used in this study. Axenization test was done by treating cysts with hydrochloric acid (3%) and Page saline containing Gentamicin (100 μg/ml). Cysts were then cultured into PYG enrich media, incubated at 30oC and the presence and proliferation of trophozoites of Acanthamoeba were observed. This study showed that PHS 15, HSB 1, HKL 48 and HKL 95 could be axenized but they have poor proliferation rate in PYG enrich media. The result showed that the difference between both clinical and environmental isolates was observed in two strains; PHS 2 and PHS 11. This indicates that there is a possibility that the physiological traits of strains from both isolates are the same and strains from the environment are able to show the pathogenic potential and capable of causing infection to human.

Acanthamoeba is a free-living amoeba that has been identified to cause Acanthamoeba keratitis and granulomatous amoebic encephalitis. Their physiological characteristics can be related to pathogenic potential which have a medical importance. This study was carried out to investigate the value of minimum cysticidal concentration of chlorine against them. Acanthamoeba strains tested were from clinical isolates from hospitals (HSB 1, HKL 48 and HKL 95) and environmental isolates (PHS 2, PHS 11 and PHS 15). The minimum cysticidal concentration of chlorine was determined by dilution process using 12 wells microtitre plate starting with 2500 ppm. 100 μl cyst suspensions standardized at 105/ml were pipetted into all wells and incubated overnight at 30°C. Cysts were then washed using Page saline and cultured on non nutrient agar overlaid with Escherichia coli. The presence of trophozoites was then observed. The lowest concentration able to prevent trophozoites formation was noted as the minimum cysticidal concentration. Minimum cysticidal concentration test showed the same concentration of 156 ppm (156 μg/ml) chlorine solution was needed to kill all cysts of Acanthamoeba isolates. This indicates that the physiological traits of environmental and clinical isolates are the same. Isolates from the environmental specimens are also able to show the pathogenic potential similar to clinical specimens, thus capable of causing disease to human.

Acanthamoeba is a free living protozoa that can cause keratitis and granulomatous amoebic encephalitis. Physiological characteristics of this amoeba are found to have a medical importance and related to the pathogenic potential of the organism. This study was carried out to investigate the physiological characteristic from the aspect of temperature tolerance. Six Acanthamoeba strains from three clinical isolates (HSB 1, HKL 48 and HKL 95) and three environmental isolates (PHS 2, PHS 11 and PHS 15) were used in this study. Test was done by culturing cysts at 30°C, 37°C and 42oC for two weeks and the ability of cysts to change to trophozoites were observed. The result showed all strain was able to change to trophozoites at 30°C and 37oC. However, no trophozoites were observed at 42oC. This indicate that there is a similarity in the physiological trait of strains from both isolates are the same and strains from the environment are able to show the pathogenic potential thus capable of causing infection to human.

This study was carried out to isolate Acanthamoeba spp. from various aquatic environments in Peninsular Malaysia. A total of 160 samples were collected with 140 samples using direct swab method and 20 samples using water collection method with 500 ml sterile Schott bottle. The swab samples were taken from water tap (50), sink (50), and swimming pool (40) while the water samples were from seawater. Swab samples were inoculated directly onto non-nutrient agar (NNA) seeded with heat-killed Escherichia coli using aseptic technique. Water samples were first filtered through a 0.45μm pore size membrane before the membrane was transferred aseptically onto NNA plate seeded with heat-killed E. coli. All plates were incubated at 30°C and examined daily for the presence of Acanthamoeba spp. up to 14 days after incubation before being declared negative. Overall, 20% samples were positive for the presence of Acanthamoeba. Positive isolation of Acanthamoeba spp. from sink and swimming pool were 20% and 30%, respectively. All three groups of Acanthamoeba genus in cyst form could be found from the collected samples.

if not treated. This study was therefore performed to evaluate the effectiveness of eyedrop antibiotics on eight Acanthamoeba spp. isolates, of which four were clinical isolates and the remaining four from the environment. Three different eyedrop antibiotics (neomycin, ciprofloxacin and gentamicin) currently available in the market and ready for use were tested. Cyst suspension from all strains were tested against eyedrop antibiotics, respectively. After 48 hours of incubation period, the solutions were filtered and the filtered membranes were put onto non-nutrient agar lawn with E. coli. Bab 3 The plates were examined daily for Acanthamoeba trophozoites under inverted microscope until day 14. Neomycin, ciprofloxacin and gentamicin were found to be effective against Acanthamoeba spp. cysts for all test strains.

Serotyping is not suffi cient to differentiate between Salmonella species that cause paratyphoid fever from the strains that cause milder gastroenteritis as these organisms share the same serotype Salmonella Paratyphi B (S. Paratyphi B). Strains causing paratyphoid fever do not ferment d-tartrate and this key feature was used in this study to determine the prevalence of these strains among the collection of S. Paratyphi B strains isolated from patients in Malaysia. A total of 105 isolates of S. Paratyphi B were discriminated into d-tartrate positive (dT+) and d-tartrate negative (dT-) variants by two lead acetate test protocols and multiplex PCR. The lead acetate test protocol 1 differed from protocol 2 by a lower inoculum size and different incubation conditions while the multiplex PCR utilized 2 sets of primers targeting the ATG start codon of the gene STM3356. Lead acetate protocol 1 discriminated 97.1% of the isolates as S. Paratyphi B dT+ and 2.9% as dT- while test protocol 2 discriminated all the isolates as S. Paratyphi B dT+. The multiplex PCR test identifi ed all 105 isolates as S. Paratyphi B dT+ strains. The concordance of the lead acetate test relative to that of multiplex PCR was 97.7% and 100% for protocol 1 and 2 respectively. This study showed that S. Paratyphi B dT+ is a common causative agent of gastroenteritis in Malaysia while paratyphoid fever appears to be relatively uncommon. Multiplex PCR was shown to be a simpler, more rapid and reliable method to discriminate S. Paratyphi B than the phenotypic lead acetate test.

This study was conducted to detect the presence of heterogenous vancomycin-intermediate Staphylococcus aureus (heteroVISA) among MRSA isolates in a major hospital. Forty-three MRSA isolates with vancomycin MIC 2 μg/ml collected in 2009 was screened for heteroVISA using Etest Glycopeptide Resistance Detection (GRD) and confirmed by population analysis profile-area under curve method. The genetic relatedness of heteroVISA strains with other MRSA was examined by pulsed-field gel electrophoresis (PFGE) method. Two isolates were shown to be heteroVISA and derived from the same clone. This showed that heteroVISA strains were already present among our local strains since 2009 and were genetically related to other susceptible strains.