Caused by the Schistosoma trematode, schistosomiasis is a disease whichcauses a host of flu-like symptoms and, in later stages, developmental disorders in children and vital organ failure in all ages. Schistosomiasis affects over 200 million people in South America, Africa, the Middle East, and Eastern Asia.
The Schistosoma haematobium, endemic in Africa and the Middle East, releases its ova around the bladder, which subsequently pass through the urine. Consequently urinalysis, where urine samples are centrifuged and viewed under a microscope, is a common way to determine the presence of Schistosoma eggs. This method of diagnosis is difficult in developing countries, where such laboratory equipment is often not readily available.
The ideal method of diagnosis must be inexpensive per individual diagnosis and can be performed outside of a laboratory setting. An alternative method of diagnosis is urine filtration to separate ova.
The proposed prototype comprises of a rubber band-fastened standard coffee filter paper within a low-cost plastic funnel and a waste collection container. Urine would pour down the funnel and pass through the filter paper with 22 μm pores, while the eggs are captured, as they are approximately 170 μm in length. Following filtration, the filter paper is taken out and clear tape is placed to extract the eggs. These eggs are then viewed under a Foldscope, a cheap paper-based microscope.
Functionality of our device was tested using a glass microbead-in-water suspension. Here, water was used to represent urine water while the microbeads were used to represent Schistosoma eggs. The device successfully filtered 45 μm diameter beads from a 10 beads/mL suspension, suggesting that our device would be a cost effective diagnostic tool in screening for schistosome eggs.
Top: (Left to right) Riti Biswas, Andrew Vaughn, Mariya Charvarha (graduate student mentor), Ashish Samaddar, and Linh Tran. Bottom: Part of the group with graduate student mentor, Ben Kim. created sample preparation strategies compatible with a portable microscope platform developed by Professor Manu Prakash’s lab. The field-ready and inexpensive techniques developed can be operated by users without special training and be used to detect infectious diseases, especially in developing countries.
Click here to see the group's poster.