A nurse draws blood from villagers in southeastern Cameroon, to add to a collection of thousands of samples that will be used by virus hunters to help detect and prevent new pathogens that might jump from tropical animals to hunters and their families. Leading the effort is Nathan Wolfe, Director of the Global Virus Forecasting Initiative (GVFI). (Cameroon village names: Ngoila, Messok, Mesock, Zoulabot)