METHODS: This cross-sectional study was conducted among 253 participants aged between 1 and 85 years. Stool samples were examined using Wheatley's trichrome stain after in-vitro cultivation in Jones' medium to detect the presence of Blastocystis. Information pertaining to the demography, socioeconomic and environment were collected using pre-validated questionnaires.
RESULTS: The total prevalence of Blastocystis infection was 40.7%. The multiple logistic regression analysis revealed that age ≥15 years (OR = 2.72; 95% CI = 1.47-5.04) and presence of infected family members (OR = 8.56; 95% CI = 4.47-16.38) were the significant risk factors associated with blastocystosis in these communities.
CONCLUSIONS: Blastocystosis is revealed through this study to be still prevalent among Orang Asli communities in rural Malaysia. The two main approaches that should be implemented by the public health authority in battling this infection would be the screening of other family members and giving treatment to the infected individuals. Moreover, it is imperative for health education on good personal and food hygiene practices are provided in order to reduce the morbidity and transmission of Blastocystis infection among the Orang Asli in their communities meaningfully.
METHODS: A cross-sectional study was conducted among aboriginal populations that reside in Pahang, Peninsular Malaysia in Feb to Mar 2015. A total of 359 stool samples were examined using Wheatley's trichrome stain, in-vitro cultivation in Jones' medium and PCR assay. Positive amplicons were subjected to sequencing and phylogenetic analysis.
RESULTS: Fifty-six (15.6%) samples were detected positive with Blastocystis sp. by Wheatley's trichrome stain and 73 (20.3%) by in-vitro culture, while PCR assay detected 71 (19.8%) positive samples. Detection rate of Blastocystis sp. was highest in combination of microscopic techniques (27.9%). The sensitivity and specificity of Wheatley's trichrome staining and in-vitro culture techniques compared to PCR assay were 49.3% (95% CI: 37.2-61.4) and 92.7% (95% CI: 89.1-95.4) and 39.4% (95% CI: 28.0-51.8) and 84.4% (95% CI: 79.7-88.4), respectively. However, the sensitivity [60.6% (95% CI: 48.3-71.9)] of the method increased when both microscopic techniques were performed together. False negative results produced by microscopic techniques were associated with subtype 3. The agreement between Wheatley's trichrome stain, in-vitro culture and combination of microscopic techniques with PCR assay were statistically significant by Kappa statistics (Wheatley's trichrome stain: K = 0.456, P<0.001; in-vitro culture: K = 0.236, P<0.001 and combination techniques: K = 0.353, P<0.001).
CONCLUSION: The combination of microscopic technique is highly recommended to be used as a screening method for the diagnosis of Blastocystis infection either for clinical or epidemiological study to ensure better and accurate diagnosis.