When someone with a high fever walks into a rural African clinic, diagnosis could be murky. The symptoms could be those of dengue, Ebola, West Nile disease, malaria or flu, and blood work results from distant labs, if available, often takes days. Now a handful of researchers are separately working on inexpensive, paper-based diagnostic tests that accurately pinpoint the cause of a disease in minutes and could speed up treatment and prevent its spread. The lack of funds and commercial partners however, means most might languish in labs.