Detection of human taeniases in Tibetan endemic areas, China

Abstract

SUMMARYDetection of taeniasis carriers of Taenia solium is essential for control of cysticercosis in humans and pigs. In the current study, we assessed the positive detection rate of a self-detection tool, stool microscopy with direct smear and coproPCR for taeniasis carriers in endemic Tibetan areas of northwest Sichuan. The self-detection tool through questioning about a history of proglottid expulsion within the previous one year showed an overall positive detection rate of more than 80% for Taenia saginata, T. solium and T. asiatica. The positive detection rate was similar for T. saginata and T. solium. In 132 taeniid tapeworm carriers, 68 (51·5%) were detected by microscopy and 92 (69·7%) were diagnosed by coproPCR. A combination of microscopy and coproPCR increased the positive detection rate to 77·3%. There remained 10 cases (7·6%) coproPCR negative but microscopy positive. Due to the high cost and complicated process, coproPCR is required for the identification of Taenia species only when necessary, though it had a significant higher positive detection rate than microscopy. Combined use of self-detection and stool microscopy are recommended in community-based mass screening for taeniases in this Tibetan area or in other situation-similar endemic regions.

Monitoring the outcomes of interventions against Taenia solium: options and suggestions

“… were successful in diagnosing taeniasis due to T. saginata in 68% of confirmed cases, and Li et al . detected as few as 51·5% of cases of T. solium or T. saginata taeniasis by faecal microscopy. In settings of a low prevalence of infection, the cost/benefit ratio of this method of assessment would be low.…”

“…Microscopic examination of faecal samples for the presence of Taenia eggs has been used frequently in epidemiological studies of taeniasis . Irrespective of the particular technique used for the examination, it is known to be relatively insensitive .…”

“…This approach has particular value in areas where T. solium , T. saginata and T. asiatica occur, as it allows differentiation between all three species. The method was assessed in a community level study in which 92 of 132 (69·7%) tapeworm carriers, confirmed by tapeworm or proglottid expulsion, were correctly diagnosed by coproPCR . Combined with microscopy, the positive detection rate increased to 102 of 132 (77·3%).…”

Role of society and culture in the epidemiology and control of foodborne parasites

“…Improvements to water supply and quality, hygiene, sanitation, and animal husbandry practices are all geared toward promoting food safety of consumed products. Detection of taeniasis carriers of T. solium using stool microscopy with direct smear and copro-PCR showed an overall parasitic burden of more than 80% in northwest Sichuan, Tibet (Li et al, 2013). The example from Jenkins et al (2013a,b) illustrated the need for international health regulations to be inclusive as they relate to foodborne parasitic diseases.…”

Control of cestode zoonoses in Asia: role of basic and applied science

“…Yamane et al (2013) present data that confirms occurrence of hybrids between T. saginata and T. asiatica. Li et al (2013) stress the usefulness of self-detection and stool microscopy in community-based mass screening for taeniases. The final article in the opening section is an overview by Wandra et al (2013) on T/C in Indonesia.…”