A two colour fluorescent assay and a kit are described that permit the determination of live and dead parasitic or non-parasitic worms, for example helminths. The assay permits screening for the effect of one or more agents or an event on the viability of a parasitic or non-parasitic worm. In one example, the assay comprises (a) providing a sample comprising one or more parasitic or non-parasitic worms (b) contacting the parasitic or non-parasitic worms with a concentration of fluorescein diacetate sufficient to yield detectable green fluorescence in any live parasitic or non-parasitic worms present in the sample and a concentration of propidium iodide sufficient to yield detectable red fluorescence in any dead parasitic or non-parasitic worms present in the sample and (c) detecting the red and green fluorescence of the parasitic or non-parasitic worms. The assay further comprises contacting the parasitic or non-parasitic worms with one or more test agents, or subjecting the parasitic or non-parasitic worms to an event. The assay allows for a rapid and objective score of parasitic or non-parasitic worm death and survival and enables the performance of high- throughput screens for the identification of potential agents against diseases such as schistosomiasis. Also described are methods and kits for discriminatory analysis of parasitic or non-parasitic worm phenotype and/or metabolics using FTIR analysis.
