Dangerous changes

Headlines about “new” infections can be misleading. Far more common are
changes in the evolution and epidemiology of known microorganisms. Ecology of
Infectious Diseases in Natural Populations (edited by B. T. Grenfell and A. P.
Dobson, Cambridge University Press £35/$59.95, ISBN 0 521 46502
8) surveys the insights now being gleaned from mathematical and modelling
approaches.