In the Soviet era, Krasnogorsk was a secret and 'closed' uranium mining town run directly from Moscow. In those days, the population was 6,500, but now it is ghost town. Scientists are struggling to identify the cause of a 'sleeping epidemic' (encephalitis) among the 130 remaining residents and in the nearby village of Kalachi in Kazakhstan (pop. 680), which causes victims to doze off for up to