On top of dealing with drones, a Taliban insurgency, and a government crackdown on that insurgency, the more than 2 million recently displaced persons in Pakistan will be forced to face a new and equally daunting challenge coming in three weeks, the rainy season and the malaria-bearing mosquitoes that soon follow.

This threat is particularly dire because the 18,000-plus families arriving every day, a migration that the United Nations Refugee Agency (UNHCR) has called one the worst since the genocide in Rwanda, have been displaced from regions, the Swat, Lower Dir, and Buner districts of the Northwest Frontier Province, where malaria is not endemic. Refugees are ill-prepared to deal with the disease both because the refugee population has no pre-existing immunity to malaria and because the flow of internally displaced people (IDPs) is quickly overwhelming available resources, including access to life-saving bednets.