Aedes Breeding Places

Three hundred thirty-six stool samples from October 2001 through October 2002 were analyzed for the presence of intestinal parasites. Fifty-six of these (16.7%) were positive for a total of 66 parasites; 65/66 (98.5%) were detected by iodine and dimethyl sulfoxide-modified acid-fast (DMSO-mAFB) stained smears of fresh and formalin-ethylacetate sedimentation concentrated samples. Saline, iodine, and DMSO-mAFB stained smears of fresh stool samples alone detected significantly fewer parasites, finding only 50/66 (75.8%) (p < 0.05). Stool samples analyzed by trichrome stained specimens preserved in Zinc sulfate polyvinyl alcohol (Zinc PVA) detected only 41/ 66 (62.2%) of the parasites. In our study population, it was necessary to perform the National Committee for Clinical Laboratory Standard (NCCLS) recommended to accurately detect intestinal parasites. The concentration technique is simple and significantly increased the detection of intestinal parasites. for itself which tests it will run, this decision must be based not only upon which procedures are requested by the physicians who use the laboratory services, the lag time during specimen collection and submission to laboratory, and the prevalence of different pathogens in their population, but must also take into account the accuracy of the diagnostic protocol (Hale et al, 1996; Garcia et al, 2001). This study was performed to evaluate the necessity of performing all of the NCCLS recommended procedures (especially the concentration technique) that are described above. To accomplish this, the parasites detected by the concentration technique of specimens preserved in 10% buffered formalin was retrospectively compared with those of the saline and iodine direct wet mounts, and DMSO-mAFB stained smears prepared from fresh stools. MATERIALS AND METHODS After informed consents were obtained, stool specimens were collected from children 3 months to 5 years of age from the Sangkhla Buri district in Kanchanaburi, a western province of Thailand along the Thai-Myanmar border. All stool specimens were processed by mixing one portion of stool to three portions of preservative SOUTHEAST ASIAN J TROP MED PUBLIC HEALTH 642 Vol 36 No. 3 May 2005 into 10% buffered formalin and Zinc PVA filled vials (James and Carol, 1999). Saline and an iodine wet mounts of fresh stools were also prepared. These slides of fresh stool smears were fixed in absolute methanol for 10 minutes and air dried before weekly shipment to AFRIMS. DMSO-mAFB staining (Bronsdon et al, 1984) for detecting Cryptosporidium and Cyclospora oocysts together with an iodine wet mount were prepared from the formalin preserved specimens after performing a formalin-ethylacetate sedimentation concentration. Trichrome staining was performed on the stool specimens preserved in Zinc PVA (Bronsdon et al, 1984; James and Carol, 1999; Garcia et al, 2001). The chi-square test for independent samples was used for statistical analysis of the results (Dean et al, 1990). A p-value of <0.05 was selected as the minimum level denoting significance.