Replication Data for: Transmission heterogeneity emerges from uncoupled parasite shedding and spreading

Here, we test whether transmission-associated processes, which are commonly assumed to covary, remain coupled across host genotypes and infection routes. Using interactions between Caenorhabditis nematodes and a wild bacterial parasite, we decompose transmission into sequential steps spanning the infection cycle, including host route-sensitivity, parasite shedding, infection-induced dispersal, and downstream infection outcomes in recipient hosts.

These components varied largely independently across host genotypes and ecological contexts, leading to repeated reordering of host transmission profiles across stages. Parasite shedding alone did not consistently predict downstream infection outcomes. Parasites from different hosts generated divergent infection burdens and virulence in standardized recipient hosts, even at comparable exposure doses.