▴Epidemic cycling and immunity. Grenfell, B. & Bjørnstad, O. Nature 27 January (2005)

In this News & Views piece, Bryan Grenfell and Ottar Bjørnstad comment on the work of Grassly et al. in the same issue of Nature in which the dynamics underlying the periodicity of syphilis epidemics in the United States are analysed using a large dataset from 68 US cities over more than 30 years.

▴A global view of epistasis. Moore, J. H. Nature Genetics January (2005)

Jason Moore comments on the impressive work of Daniel Segrè et al. in which single and double knockouts for almost 900 metabolic genes were generated and the corresponding growth phenotypes were analysed by metabolic flux analysis.

●Nuclear RNA export unwound. Cullen, B. R. Nature 6 January (2005)

●Knockout malaria vaccine? Ménard, R. Nature 13 January (2005)

●Vietnam's war on flu. Aldhous, P. Nature 13 January (2005)

●Bacteria spurned by self-absorbed cells. Gorvel, J. -P. & de Chastellier, C. Nature Medicine January (2005)

In this News & Views article, Jean-Pierre Gorvel and Chantal de Chastellier comment on three recent studies detailing the host autophagic response to Shigella flexneri, Mycobacterium tuberculosis and group A Streptococcus, which emphasize the role of autophagy as an innate immune mechanism.

●Sorting out metagenomes. Handlesman, J. Nature Biotechnology January (2005)

● Variability is its specialty . Brower, V. EMBO Reports January (2005)

An EMBO Reports analysis of the prospect of an avian influenza epidemic.

●Ethanol fermentation on the move. Jeffries, T. W. Nature Biotechnology January (2005)

The complete genome sequence of the ethanologenic bacterium Zymomonas mobilis is reported in this issue of Nature Biotechnology. In the accompanying News & Views, Jeffries profiles Z. mobilis, which has an ethanol production rate that is three- to fivefold higher than that of S. cerevisiae, and looks to the genome sequence for clues for performance enhancement.