Experimental transmission of Karshi and Langat (tick-borne encephalitis virus complex) viruses by Ornithodoros ticks (Acari: Argasidae)
Journal of Medical Entomology
Karshi virus; Mosquitoes; Ornithodoros; Tick-borne encephalitis virus; Vector competency
Selected species of mosquitoes and Ornithodoros ticks were evaluated for their potential to transmit Karshi and Langat (tick-borne encephalitis virus complex) viruses in the laboratory. Although there was no evidence of replication of Karshi virus in either of the two mosquito species tested [Ochlerotatus taeniorhynchus (Wiedemann) or Culex pipiens (L.)], Karshi virus replicated in and was transmitted by all three species of Ornithodoros ticks tested (Ornithodoros parkeri Cooley, Ornithodoros sonrai Sautet & Witkowski, and Ornithodoros tartakovskyi Olenev). When inoculated with Karshi virus, 90% of Ornithodoros ticks (44/49) transmitted this virus by bite to suckling mice, and transmission continued to occur for at least 1 yr, the longest extrinsic incubation tested. After feeding on a suckling mouse with a viremia of ≈105 suckling mouse subcutaneous lethal dose50 units of Karshi virus per milliliter of blood, all three species of Ornithodoros tested became infected with and transmitted Karshi virus both trans-stadially and horizontally by bite to suckling mice. In addition, female O. tartakovskyi transmitted Karshi virus vertically to their progeny. In a continuation of a previous study, O. sonrai, orally exposed to Langat virus, were able to transmit this virus after >3 yr, the longest interval tested. Therefore, Ornithodoros spp. should be considered as potential vectors and as possible long-term maintenance hosts for Karshi virus and other members of the tick-borne encephalitis virus complex.
Turell, M., Mores, C., Lee, J., Paragas, J., Shermuhemedova, D., Endy, T., & Khodjaev, S. (2004). Experimental transmission of Karshi and Langat (tick-borne encephalitis virus complex) viruses by Ornithodoros ticks (Acari: Argasidae). Journal of Medical Entomology, 41 (5). http://dx.doi.org/10.1603/0022-2585-41.5.973