2,500 adults, 623 children so far vaccinated in the Republic of Tuva to prevent flea-spreading of the decease.
All 17 people he was in contact with - six of them children - are also quarantined to prevent spread of one of world's most deadly infectious diseases.
US, Dutch, Swiss, Swedish, South Korean, German and Russian tourists banned from leaving the area.
Russian tourists stuck in western Mongolia after closure of frontier to stop spread of infection.
Centre is one of only two repositories in the world of smallpox virus, and a key hub of research into the planet's deadliest diseases.