For many first world travelers, a trip to the tropics ends in diarrhea, which can be challenging for physicians to diagnose, due to the large number of organisms that can cause that illness. Researchers in Switzerland report some success with the use of a multiplex nucleic acid test in identifying pathogens in returning travelers, both adults and children. Although the multiplex test did not cover Blastocystis, results suggest that this might be an appropriate addition to the assay. The test was more successful at identifying pathogens in children, with 52% of samples from children showing positives, with rotavirus being the most common at 27%. Adult samples were positive only 11% of the time, but a separate microscopic examination showed Blastocystis infection in 23% of those individuals. The study was published in the journal Infection.