Epidemiologist and infectious disease specialist Vadim Pokrovsky, one of the country’s leading experts on HIV/AIDS and a key figure in the Soviet and Russian response to the epidemic, has died at the age of 71, public health watchdog Rospotrebnadzor said Wednesday. Pokrovsky led the specialized AIDS epidemiology and prevention laboratory at the Central Research Institute of Epidemiology under the Soviet Health Ministry and later Rospotrebnadzor until 2001. He then headed the Federal Scientific and Methodological Center for HIV Prevention and Control.