The Role of Australian Mosquito Species in the Transmission of Endemic and Exotic West Nile Virus Strains

Abstract

Recent epidemic activity and its introduction into the Western Hemisphere have drawn attention to West Nile virus (WNV) as an international public health problem. Of particular concern has been the ability for the virus to cause outbreaks of disease in highly populated urban centers. Incrimination of Australian mosquito species is an essential component in determining the receptivity of Australia to the introduction and/or establishment of an exotic strain of WNV and can guide potential management strategies. Based on vector competence experiments and ecological studies, we suggest candidate Australian mosquito species that would most likely be involved in urban transmission of WNV, along with consideration of the endemic WNV subtype, Kunjin. We then examine the interaction of entomological factors with virological and vertebrate host factors, as well as likely mode of introduction, which may influence the potential for exotic WNV to become established and be maintained in urban transmission cycles in Australia.

The effect of riboflavin and ultraviolet light on the infectivity of arboviruses

“…Although the amount of virus required for transfusion transmission is not known, this suggests that high levels of viremia may be required to transmit virus by transfusion, a probability that may be further reduced with even modest reduction in infectious titer of these agents. Moreover, PRT has the added potential benefits of negating the need for implementing new screening tests in particular areas, where a suitable test may exist but is either not yet available or not yet in use, such as malaria screening in the United States or Canada or WNV testing in Australia, as well as eliminating the need for certain travel‐related donation deferrals, which may have a flow on effect of addressing accessibility issues. Studies have also demonstrated that PRT appears to be as cost‐effective as other blood safety methods .…”

Spatial and Temporal Distribution of West Nile Virus in Horses in Israel (1997–2013) - from Endemic to Epidemics

“…Despite the presence of WNV in most of the United States already a decade ago and its spread to all regions of the continental US throughout this decade [13] , WNV epidemic activity was demonstrated in 2012, in which more human disease cases were reported nationally than any year since 2003. This outbreak resulted in 2,873 cases of neuroinvasive disease and 286 human deaths [14] , [15] . Available data suggest that the increased incidence of WNV disease in 2012 was not likely caused by genotypic changes in the circulating virus strains and it was suggested that a number of inter-related factors, including weather, abundance of birds that maintain the virus, abundance of mosquitoes that spread the virus, and human behaviour are all contributors to the disease epidemics [16] .…”

Climate change impacts on West Nile virus transmission in a global context

“…The season of arbovirus activity might be prolonged, with potential transmission increase [101]. Moreover, as a result of temperature increase, the vectors are expected to move further south into currently cooler regions because summer temperatures in southern areas will be more adequate for initiating and maintaining the virus amplification [102,103].…”