title: Laboratory investigation of smallpox patients with particular reference to infectivity in the early stages.
authors.forename: F O
authors.initials: FO
authors.lastname: MacCALLUM
authors.forename: C A
authors.initials: CA
authors.lastname: McPHERSON
authors.forename: D F
authors.initials: DF
authors.lastname: JOHNSTONE
mesh_terms: D006801:Humans; D007753:Laboratories; D012899:Smallpox; D012901:Variola virus