1 Medical and Veterinary Entomology, Institut Pasteur du Cambodge, 5 Bd Monivong, Phnom Penh, Cambodia. Electronic address: sebastien.boyer@pasteur.fr.
2 Department of Environmental Sciences and Program in Population Biology, Ecology, and Evolution, Emory University, Atlanta, GA, USA; Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA.