Optically Based Hand-Held Sensor for Visualization and Quantification of Cryptosporidium Parvum

Abstract

The ingestion of the protozoan parasite Cryptosporidium, resulting in the associated disease cryptosporidiosis, can cause major problems if introduced into a water supply for both animals and humans. This research focuses on the creation of a sensor to track and quantify the parasite with a digital camera system using Digital Inline Holographic Microscopy (DIHM) and software reconstruction. Since Cryptosporidium oocysts are not single celled and can be around 4–8 µm in diameter, they are easily detected with the DIHM at various depths within a 3.5 mL cuvette. As the sensor is improved by modifications, it could pick up behavior of movement and sizes of particles measured to positively identify the particle(s) being tracked as Cryptosporidium as others have achieved on Escherichia coli and other microorganisms. A significant advantage of this technique is the resulting sensor costs significantly less than traditional microscopes used in laboratory tests for detecting Cryptosporidium, or other methods like USEPA Method 1623 and can provide results within minutes. The sensor is a stellar alternative to current methods in detecting and quantifying Cryptosporidium.