Transmission of ChimeriVax-DEN2 virus by vector mosquitoes is unlikely.

2002 DEC 4 - (NewsRx.com & NewsRx.net) -- Study results indicate that the live virus contained in the ChimeriVax-DEN2 vaccine (Acambis, Inc.) has limited ability to infect and replicate in Aedes aegypti and Ae. albopictus mosquitoes.

"The chimeric yellow fever (YF) 17D-dengue type 2 (ChimeriVax-DEN2) vaccine virus...contains the prM and E genes of wild-type (wt) dengue 2 (DEN-2) (strain PUO-218) virus in the YF vaccine virus (strain 17D) backbone," stated B.W. Johnson and colleagues at the U.S. Centers for Disease Control and Prevention's Division of Vector-Borne Infectious Diseases, National Center for Infectious Diseases.

The researchers wanted to determine if the ChimeriVax-DEN2 virus could infect the two Aedes species - Ae aegypti being the main mosquito vector of DEN and YF viruses, and Ae. albopictus occurring in areas of active transmission of YF and DEN viruses - and subsequently by transmitted by them.

"Mosquitoes were intrathoracically (IT) inoculated with virus or were fed a virus-laden blood meal, and the replication kinetics of ChimeriVax-DEN2 were compared with the wt DEN-2 and YF 17D vaccine viruses," Johnson's team said (Growth characteristics of ChimeriVax-DEN2 vaccine virus in Aedes aegypti and Aedes albopictus mosquitoes. Am J Trop Med Hyg, 2002;67(3):260-265).

They reported, "Replication of YF 17D virus is attenuated in cultured Ae. albopictus C6/36 mosquito cells and in Ae. aegypti and Ae. albopictus mosquitoes. Growth of ChimeriVax-DEN2 virus similarly was restricted in C6/36 cells and in mosquitoes.

"ChimeriVax-DEN2 replicated in 56% of IT inoculated Ae. aegypti, and virus ...