Orthopoxvirus DNA from representative strains of rabbitpox, vaccinia, monkeypox, variola, cowpox and ectromelia viruses was analysed by cleavage with restriction endonucleases HindIII, XhoI or SmaI. Genome mol. wt. vary from about 120 x 10(6) for rabbitpox to about 145 x 10(6) for cowpox. Physical maps of cleavage sites are similar and characteristic for strains of the same Orthopoxvirus type. ...

1. The global eradication of smallpox was confirmed in 1980 (resolution WHA33.3). From 1981 to 1986, WHO undertook a programme to implement the post-eradication policies contained in the 1979 report of the Global Commission for the Certification of Smallpox Eradication and endorsed by the Health Assembly in resolution WHA33.4. Progress was reviewed year by year from 1981 to 1984 by the WHO Comm...

RILEY, JEAN M. (U.S. Army Biological Laboratories, Fort Detrick, Frederick, Md.), AND MICHAEL D. ORLANDO. Singledose assay technique for variola virus. Appl. Microbiol. 12:7-9. 1964.-A biological assay for variola virus was needed that would (i) require a minimum of time and (ii) have acceptable precision. Preliminary titrations made in 11-day-old embryonated eggs and in suckling mice (6 to 24 ...

The studies reported here describe the successful propagation of variola virus in spinner cultures of mammalian cells, and the factors which influence its growth. Five established cell lines were used for the propagation of variola virus in a spinner culture system. Low doses of virus did initiate an infection but virus yields did not approach those obtained when an intermediate inoculum was us...