Data from: Light pollution increases West Nile virus competence of a ubiquitous passerine reservoir species

Among the many anthropogenic changes that impact humans and wildlife, one
of the most pervasive but least understood is light pollution. Although
detrimental physiological and behavioral effects resulting from exposure
to light at night are widely appreciated, the impacts of light pollution
on infectious disease risk have not been studied. Here, we demonstrate
that artificial light at night (ALAN) extends the infectious-to-vector
period of the house sparrow (Passer domesticus), an urban-dwelling avian
reservoir host of West Nile virus (WNV). Sparrows exposed to ALAN
maintained transmissible viral titers for two days longer than controls
but did not experience greater WNV-induced mortality during this window.
Transcriptionally, ALAN altered the expression of gene regulatory networks
including key hubs (OASL, PLBD1, TRAP1) and effector genes known to affect
WNV dissemination (SOCS). Despite mounting anti-viral immune responses
earlier, transcriptomic signatures indicated that ALAN-exposed individuals
likely experienced pathogen induced damage and immunopathology,
potentially due to evasion of immune effectors. A simple mathematical
modelling exercise indicated that ALAN-induced increases of host
infectious-to-vector period could increase WNV outbreak potential by ~41%.
ALAN likely affects other host and vector traits relevant to transmission,
and additional research is needed to advise management of zoonotic
diseases in light polluted areas.