Sigmoidal function of infectionsSubmitted by editor on 3 February 2017.Get the paper!
Infectious diseases that can be contracted from the environment form a
persistent threat to human health, livestock and wildlife. With the
changing environment, there is increasing need for predictive
modelling of environmentally transmitted disease dynamics.
Understanding the dose-response relationship is the key to this end,
but theory and experimental work rarely go hand in hand, and there are
numerous difficulties in comparing experimental and modelling
Our work provides both theoretical and empirical support for a
sigmoidally shaped functional form, a modelling tool, that relates the
environmental pathogen load to the expected waiting time until an
infection occurs. This functional form takes into account the
co-operative effort of pathogens in defeating the immune system, and
is biologically sound for many bacterial diseases, such as cholera.
Our results provide a basis for using a more realistic functional form
in environmental disease transmission, and underline the need for
experimental validation of the very basic building blocks used in