Malaria remains a major public health burden in some world regions. In 2018, 237,000 cases were reported in Brazil, 91.5% of them caused by the parasite Plasmodium vivax. A new malaria drug known as tafenoquine was recently approved by several medicines regulatory authorities to treat P. vivax. Scientists from the Institut Pasteur, in partnership with the Oswaldo Cruz Foundation (Fiocruz) in Rio de Janeiro, Brazil, have modeled the effect of introducing this new drug.