(NYT) – A Russian researcher, who died from an unknown illness, worked at a remote anti-plague facility. Few foreigners have visited these labs, which dot the former Soviet states, and are shrouded in secrecy.

The institute in Irkutsk never functioned as a military facility, but it was part of the broad yet secretive “Anti-Plague System.” At hundreds of field sites and labs across the Soviet Union, thousands of researchers were responsible for tracking emerging strains of plague and other endemic diseases, exterminating disease-causing rodents and developing vaccines. These facilities, experts said, had also provided pathogen samples to the military labs responsible for creating bioweapons during the Soviet era.

Most of these facilities are still functioning, and while those in Russia remain closely-guarded, some in former Soviet states have opened their doors to international researchers looking to learn about the fabled system. (Read More)