Infections that consist of multiple parasite strains or species are common in the wild and are
a major public health concern. Theory suggests that these infections have a key influence on …

Humans are changing the environmental conditions of our planet, and animal immune
functions are being affected by these modifications. For instance, a diversity of chemical …

Co-infections by multiple pathogen strains are common in the wild. Theory predicts co-
infections to have major consequences for both within-and between-host disease dynamics …

Ecological changes affect pathogen epidemiology and evolution and may trigger the
emergence of novel diseases. Aquaculture radically alters the ecology of fish and their …

The evolution of drug-resistant pathogens is a major challenge for 21st century medicine.
Drug use practices vigorously advocated as resistance management tools by professional …

Infections frequently contain multiple strains (genotypes) of the same pathogen, yet they are
still usually treated as uniform entities. In this Review, we discuss problems with inconsistent …

Competition between parasite species or strains within hosts is a major evolutionary force in
infections. In response, parasites exhibit a diverse array of strategies that improve their …

The discussion of host–parasite interactions, and of parasite virulence more specifically, has
so far, with a few exceptions, not focused much attention on the accumulating evidence that …

Adult coho salmon O ncorhynchus kisutch return each autumn to freshwater spawning
habitats throughout western N orth A merica. The migration coincides with increasing …

Humans and animals often become coinfected with pathogen strains that differ in virulence.
The ensuing interaction between these strains can, in theory, be a major determinant of the …