The Possible Use of Temperature-Sensitive Conditional Lethal Mutants for Immunization in Viral Infections
South Africa and Australia were invaded and colonized by-European man less than 200 years ago. In both places the settlers found ample grasslands and savannah-woodlands and an equable Mediterranean type of climate, and they soon introduced all the kinds of domestic animals that they had known in Europe. The impact of infectious diseases on these herds differed greatly in the two continents. Australia had been separated biogeographically from the rest of the world ever since the initial breakup of Pangaea, some 180 million years ago, and the only grazing animals there were marsupials, most of which were small in size and few in number. The rickettsial infection, Q fever, is the only disease that Australians have recognized as having been transferred to cattle and sheep from a marsupial reservoir host, and it caused trivial disease in the domestic as in the native animals. South Africa, on the other hand, is at the southern tip of a continent on which dwell a greater variety and a larger number of indigenous grazing animals than are found on any other continent. Wave after wave of novel infections, of differing virulence but often quite severe in the introduced species, emerged from this reservoir to assail one or another of the local domestic animals.
KeywordsInfluenza Virus Respiratory Syncytial Virus Rabies Virus Semliki Forest Virus Restrictive Temperature
Unable to display preview. Download preview PDF.
- 1.BEVERIDGE, W.I.B. & BURNET, F.M. Med. Res. Council Spec. Rept. Sci. 256, 1946.Google Scholar
- 3.HADORN, E. “Developmental Genetics and Lethal Factors”, p. 118, Methuen, London, 1961.Google Scholar
- 6.EDGAR, R.S. Conditional lethals, in: “Phage and the Origins of Molecular Biology”, p. 166. (Eds. J. Cairns, G.S. Stent and J.D. Watson), Cold Spring Harbor Lab. N.Y., 1966.Google Scholar
- 10.FENNER, F. Unpublished data, 1965.Google Scholar
- 16.CHANOCK, R.M. Unpublished data, 1972.Google Scholar