title: Defining the Risk of Zika and Chikungunya Virus Transmission in Human Population Centers of the Eastern United States.
abstract: The recent spread of mosquito-transmitted viruses and associated disease to the Americas motivates a new, data-driven evaluation of risk in temperate population centers. Temperate regions are generally expected to pose low risk for significant mosquito-borne disease; however, the spread of the Asian tiger mosquito (Aedes albopictus) across densely populated urban areas has established a new landscape of risk. We use a model informed by field data to assess the conditions likely to facilitate local transmission of chikungunya and Zika viruses from an infected traveler to Ae. albopictus and then to other humans in USA cities with variable human densities and seasonality. Mosquito-borne disease occurs when specific combinations of conditions maximize virus-to-mosquito and mosquito-to-human contact rates. We develop a mathematical model that captures the epidemiology and is informed by current data on vector ecology from urban sites. The model demonstrates that under specific but realistic conditions, fifty-percent of introductions by infectious travelers to a high human, high mosquito density city could initiate local transmission and 10% of the introductions could result in 100 or more people infected. Despite the propensity for Ae. albopictus to bite non-human vertebrates, we also demonstrate that local virus transmission and human outbreaks may occur when vectors feed from humans even just 40% of the time. Inclusion of human behavioral changes and mitigations were not incorporated into the models and would likely reduce predicted infections. This work demonstrates how a conditional series of non-average events can result in local arbovirus transmission and outbreaks of human disease, even in temperate cities.
authors.affiliation: Center for Computational Science Tulane University New Orleans, LA, United States of America.|Theoretical Biology and Biophysics Los Alamos National Laboratory Los Alamos, NM, United States of America.|New Mexico Consortium, Suite 301 Los Alamos, NM, United States of America.
authors.forename: Carrie A
authors.initials: CA
authors.lastname: Manore
authors.affiliation: Cary Institute of Ecosystem Studies Box AB, 2801 Sharon Turnpike Millbrook, NY United States of America.
authors.forename: Richard S
authors.initials: RS
authors.lastname: Ostfeld
authors.affiliation: Department of Ecology and Evolutionary Biology University of Kansas Haworth Hall Lawrence, Kansas, United States of America.
authors.forename: Folashade B
authors.initials: FB
authors.lastname: Agusto
authors.affiliation: Department of Biological Sciences Old Dominion University Norfolk, VA, United States of America.|Mathematics, Statistics and Computer Science University of KwaZulu-Natal Durban, South Africa.
authors.forename: Holly
authors.initials: H
authors.lastname: Gaff
authors.affiliation: Cary Institute of Ecosystem Studies Box AB, 2801 Sharon Turnpike Millbrook, NY United States of America.
authors.forename: Shannon L
authors.initials: SL
authors.lastname: LaDeau
mesh_terms: D000330:Aedes / Q000502:physiology / Q000821:virology; D000818:Animals; D065632:Chikungunya Fever / Q000635:transmission* / Q000821:virology; D002646:Chikungunya virus / Q000502:physiology*; D002947:Cities; D006801:Humans; D007303:Insect Vectors / Q000502:physiology / Q000821:virology; D008962:Models, Theoretical; D014481:United States; D000071244:Zika Virus / Q000502:physiology*; D000071243:Zika Virus Infection / Q000635:transmission* / Q000821:virology