title: Dengue transmission model by means of viremic adult immuno-competent mouse.
abstract: BACKGROUND
  Dengue virus infection manifests in three distinct forms in humans: dengue fever, dengue hemorrhagic fever, and dengue shock syndrome. Infection with the virus is a fatal disease; no vaccine is available and prevention depends on interruption of the chain of transmission. The study of dengue viral transmission by mosquitoes is hindered due to the lack of an affordable animal model. In general, immuno-competent mice are used as a simple and inexpensive animal model, but mice are not susceptible to dengue virus infection and therefore viremia will not occur following the inoculation of the virus in such mice. Here, we report a method for creating artificial viremia in immuno-competent mice, and further demonstrate the use of viremic mice to simultaneously infect a large number of Aedes aegypti.
  
  
  METHODS
  We infected K562 cells with DENV-2 in the presence of an antibody against DENV-4. We then incubated the cells for 2 d before injecting the infected cells into C3H mice. After 5 h incubation, we allowed 100-150 female Aedes aegypti to feed on blood from the mice directly. We collected blood samples from the mice and from randomly selected Ae. aegypti at 2, 6, 12, and 24 h post-blood meal and screened the samples for DENV-2 genome as well as for virus concentration.
  
  
  RESULTS
  Our procedure provided high virus concentrations in the mice for at least 7 h after viral inoculation. We found that 13 out of 14 randomly picked mosquitoes were infected with DENV-2. High concentrations of virus were detected in the mosquitoes until at least 12 h post-infection.
  
  
  CONCLUSIONS
  Using the viremic immuno-competent mouse, we show that mass infection of Ae. aegypti is achievable. Compared to other infection techniques using direct inoculation, membrane-feeding, or immuno-deficient/humanized mice, we are confident that this method will provide a simpler and more efficient infection technique.
authors.affiliation: Department of Infectious Disease Control, Faculty of Medicine, Oita University, Oita 879-5593, Japan. luckyruntuwene@oita-u.ac.jp.
authors.forename: Lucky Ronald
authors.initials: LR
authors.lastname: Runtuwene
authors.forename: Eiji
authors.initials: E
authors.lastname: Konishi
authors.forename: Atsushi
authors.initials: A
authors.lastname: Yamanaka
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Makino
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Takasaki
authors.forename: Ichiro
authors.initials: I
authors.lastname: Kurane
authors.forename: Takashi
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Yuki
authors.initials: Y
authors.lastname: Eshita
mesh_terms: D000330:Aedes / Q000502:physiology* / Q000821:virology; D000818:Animals; D002460:Cell Line; D003715:Dengue / Q000635:transmission* / Q000821:virology; D003716:Dengue Virus / Q000502:physiology*; D005260:Female; D051379:Mice; D008809:Mice, Inbred C3H; D014766:Viremia