Epizootic activity of Murray Valley encephalitis and Kunjin viruses in an aboriginal community in the southeast Kimberley region of Western Australia: results of mosquito fauna and virus isolation studies.
We undertook annual surveys of flavivirus activity in the community of Billiluna in the southeast Kimberley region of Western Australia between 1989 and 2001 [corrected]. Culex annulirostris was the dominant mosquito species, particularly in years of above average rains and flooding. Murray Valley encephalitis (MVE) virus was isolated in 8 of the 13 years of the study from seven mosquito species, but more than 90% of the isolates were from Cx. annulirostris. The results suggest that MVE virus is epizootic in the region, w ith activity only apparent in years with average or above average rainfall and increased numbers of Cx. annulirostris. High levels of MVE virus activity and associated human cases were detected only once (in 1993) during the survey period. Activity of MVE virus could only be partially correlated with wet season rainfall and flooding, suggesting that a number of other factors must also be considered to accurately predict MVE virus activity at such communities.
Broom
Annette K
AK
Arbovirus Surveillance and Research Laboratory, Department of Microbiology, The University of Western Australia, Nedlands, Western Australia. abroom@cyllene.uwa.edu.au
Lindsay
Michael D A
MD
Wright
Anthony E
AE
Smith
David W
DW
Mackenzie
John S
JS
D000818:Animals; D003465:Culex / Q000821:virology*; D009033:Culicidae / Q000145:classification / Q000821:virology; D004196:Disease Outbreaks; D018068:Encephalitis Virus, Murray Valley / Q000302:isolation & purification*; D004671:Encephalitis, Arbovirus / Q000453:epidemiology / Q000517:prevention & control / Q000635:transmission*; D006801:Humans; D007303:Insect Vectors / Q000821:virology*; D009032:Mosquito Control; D044382:Population Groups; D011891:Rain; D012307:Risk Factors; D012621:Seasons; D014901:West Nile Fever / Q000453:epidemiology / Q000517:prevention & control / Q000635:transmission; D014902:West Nile virus / Q000302:isolation & purification*; D014904:Western Australia / Q000453:epidemiology