Incidence of West Nile Virus in House Sparrow Nestlings in Relation to Parental Effort

The house sparrow, Passer domesticus, is known to be an important host of West Nile (WN) virus and may contribute to the transmission of WN virus to humans. However, little is known about the factors that influence the occurrence of WN virus in birds. I conducted a study to determine if parental care was related to the rates of WN virus infections among nestling birds. I observed house sparrow nests for one hour periods noting the time the male and female parent spent on the nest box, in the nest box, and the number of food trips, as measures of parental care. Each nestling was then tested for WN virus by PCR and gel electrophoresis. I found that, as the summer progressed, WN virus infections increased and each measure of parental care decreased. Although a number of factors may have contributed to lower parental care, my data shows that WN virus infections increased as parental effort decreased