title: Microevolution of Dengue viruses circulating among primary school children in Kamphaeng Phet, Thailand.
abstract: To determine the extent and structure of genetic variation in dengue viruses (DENV) on a restricted spatial and temporal scale, we sequenced the E (envelope) genes of DENV-1, -2, and -3 isolates collected in 2001 from children enrolled in a prospective school-based study in Kamphaeng Phet, Thailand, and diagnosed with dengue disease. Our analysis revealed substantial viral genetic variation in both time and space, with multiple viral lineages circulating within individual schools, suggesting the frequent gene flow of DENV into this microenvironment. More-detailed analyses of DENV-2 samples revealed strong clustering of viral isolates within individual schools and evidence of more-frequent viral gene flow among schools closely related in space. Conversely, we observed little evolutionary change in those viral isolates sampled over multiple time points within individual schools, indicating a low rate of mutation fixation. These results suggest that frequent viral migration into Kamphaeng Phet, coupled with population (school) subdivision, shapes the genetic diversity of DENV on a local scale, more so than in situ evolution within school catchment areas.
authors: Armed Forces Research Institute of Medical Sciences, 315/6 Rajvithi Road, Bangkok, Thailand 10400. Richard.Jarman@afrims.org
authors: Richard G
authors: RG
authors: Jarman
authors: Edward C
authors: EC
authors: Holmes
authors: Prinyada
authors: P
authors: Rodpradit
authors: Chonticha
authors: C
authors: Klungthong
authors: Robert V
authors: RV
authors: Gibbons
authors: Ananda
authors: A
authors: Nisalak
authors: Alan L
authors: AL
authors: Rothman
authors: Daniel H
authors: DH
authors: Libraty
authors: Francis A
authors: FA
authors: Ennis
authors: Mammen P
authors: MP
authors: Mammen
authors: Timothy P
authors: TP
authors: Endy
mesh_terms: D002648:Child; D015331:Cohort Studies; D003715:Dengue / Q000097:blood / Q000453:epidemiology* / Q000821:virology*; D003716:Dengue Virus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D005838:Genotype; D006801:Humans; D010802:Phylogeny; D013785:Thailand