Availability There are two World Health Organisation - approved repositories of variola virus - one at the US Center for Disease Control and the other in Novosibirsk, Russia. (news.bbc.co.uk)
They were surprised to find that the samples contained a small number of fragments of variola virus — the genetic remains of infection with the virus that causes smallpox. (acsh.org)
«If smallpox is present, and it's variola major, you should see epidemics.» (acsh.org)