“…Incomplete elusion of oocysts during the concentration stage often leads to a recovery rate of less than 15%, while in the later stage of IMS-FA, a recovery rate of over 95% is commonly achieved. 212,213 The actual recovery rate varies depending on water quality and turbidity, but USEPA 1623.1 considers a 38% recovery rate acceptable. Depending on the sample to be analysed, and the actual concentration of the oocysts in a sample, this recovery will allow to detect or even quantify the oocysts.…”