A study conducted at the University of Campinas (UNICAMP) in Brazil shows that triclosan, an antimicrobial compound used in soap, toothpaste, deodorant and many other products, can inhibit target genes in the malaria parasite during two crucial stages of its life cycle in humans—the hepatic stage, when it reproduces in the host’s liver cells, and the erythrocytic stage, when it infects red blood cells.