Vector competence of Australian mosquito species for a North American strain of West Nile virus.
Since the establishment of West Nile virus (WNV) into the United States, concern has arisen that this virus may also pose a serious threat to Australian biosecurity. The vector competence of 19 Australian mosquito species for a North American strain of WNV was evaluated. Mosquitoes collected from Cairns, Brisbane, and Sydney were exposed to blood containing 10(4.0+/-0.3) cell culture infectious dose(50)/mosquito WNV that was isolated from a crow during the 1999 New York outbreak. Mosquitoes were tested 12-15 days later to determine their infection, dissemination, and transmission rates. A number of Culex spp. demonstrated a high vector competence for this virus, with some populations of Culex annulirostris, the primary Australian Kunjin virus vector, displaying transmission rates up to 84%. Similarly, Cx. quinquefasciatus and Cx. gelidus were highly competent, with infection and transmission rates of >80% and >50%, respectively. Common Aedes spp., including Aedes notoscriptus, Ae. vigilax, and Ae. procax, were moderately susceptible, and some Verrallina spp. and Coquillettidia spp. were relatively refractory to infection. Thus, Australia possesses a number of competent mosquito species that could facilitate local transmission of WNV, should it be introduced.
Jansen
Cassie C
CC
Australian Biosecurity Cooperative Research Centre, University of Queensland, St. Lucia, Australia. cassie_jansen@health.qld.gov.au
Webb
Cameron E
CE
Northill
Judith A
JA
Ritchie
Scott A
SA
Russell
Richard C
RC
Van den Hurk
Andrew F
AF
D000818:Animals; D001315:Australia; D009033:Culicidae / Q000821:virology*; D007303:Insect Vectors / Q000821:virology*; D009656:North America; D014902:West Nile virus / Q000145:classification*