UC Berkeley

Limiting the environmental transmission of soil-transmitted helminths (STHs), which infect 1.5 billion people worldwide, will require sensitive, reliable, and cost-effective methods to detect and quantify STHs in the environment. We review the state-of-the-art of STH quantification in soil, biosolids, water, produce, and vegetation with regard to four major methodological issues: environmental sampling; recovery of STHs from environmental matrices; quantification of recovered STHs; and viability assessment of STH ova. We conclude that methods for sampling and recovering STHs require substantial advances to provide reliable measurements for STH control. Recent innovations in the use of automated image identification and developments in molecular genetic assays offer considerable promise for improving quantification and viability assessment. The state-of-the-art and key developments in environmental methods for sampling, recovery and concentration, quantification, and viability assessment of soil-transmitted helminths (STHs) are reviewed. Optimal protocols for sampling and recovery of STHs from environmental samples have not been developed and systematic investigation is needed. Recent advances in genetic assays and automated image analysis for quantification and viability assessment offer improved sensitivity, reliability, and sample throughput.