Blood samples from patients in Cambodia, Myanmar, Vietnam, and Thailand showed drug-resistant malaria parasites are now entrenched. While time is short, says the study published in the New England Journal of Medicine, the authors argued that increasing the standard treatment to six days from three could help fight resistance. “It may still be possible to prevent the spread of artemisinin-resistant malaria parasites across Asia and then to Africa by eliminating them, but that window of opportunity is closing fast,” said Nicholas White, a professor of tropical medicine at Britain’s Oxford University. If it gets worse, this will have been the third major drug that the parasites will have developed resistance to since the 1950s. Patients from Kenya, Nigeria, and the Democratic Republic of the Congo did not show signs of resistance.