Assessing the impact of a joint human-porcine intervention package for Taenia solium control: Results of a pilot study from northern Lao PDR

Following confirmation that a remote village of approximately 300 inhabitants in northern Lao PDR was hyperendemic for the Neglected Tropical Disease Taenia solium, a pilot human-porcine therapeutic control intervention was implemented between October 2013 and November 2014. Mass drug administration with a three day albendazole 400 mg protocol was offered to all eligible humans in October 2013 and March 2014. At these times, and again in October 2014, eligible village pigs received the anti-cysticercosis TSOL18 vaccination and an oral dose of oxfendazole anthelmintic at 30 mg/kg, both repeated one month later. Community and individual human taeniasis prevalences were estimated via copro-antigen ELISA of volunteered human faecal samples prior to October 2013, and again in January 2015, in order to examine the short term impact of the intervention. Pre and post intervention analysis demonstrated a 78.7% decrease in crude prevalence within the target area during this time, from 30.6% (95% C.I. 25.5–38.9%) to 6.5% (95% C.I 3.4–9.5%). When results were adjusted for the sensitivity and specificity of the diagnostic assays, the intervention appeared to result in a significant (χ2 = 40.7 p < 0.0001) reduction. A subset of 48 individuals followed throughout the study period demonstrated similar results to the community level findings, with crude pre and post intervention estimates of 22.9% (95% C.I. 10.8–35.0%) and 6.25% (95% C.I. 0–13.5%), respectively, which again suggests a significant (McNemar χ2 = 32.23 p < 0.0001) reduction when the diagnostic parameters were accounted for. This pilot study is the first of its kind to investigate T. solium control opportunities in Southeast Asia, demonstrating that treatment of both humans and pigs in a given target area with a recommended anthelmintic protocol can result in a significant decrease in human taeniasis levels over a relatively short period of time. Moreover, this study provides the first data on the impact of a combined human-porcine therapeutic intervention upon the adult parasite in the human host. This research contributes to the current requirement for evidence of successful T. solium control under various Neglected Tropical Disease policy narratives, although further research is required to assess the impact, feasibility and cost effectiveness of this approach on a broader scale