mosquito feeding patterns and natural infection of vertebrates with ross river and barmah forest viruses in brisbane, feeding patterns of mosquitoes were assessed through the identification of 865 blood meals collected from brisbane during 2000-2001. under natural conditions, mosquito feeding (including that of culex annulirostris, aedes vigilax, and aedes notoscriptus) was primarily on dogs (37.4%), but also on birds (18.4%), horses (16.8%), brushtail possums (13.3%), humans (11.6%), and cats, flying foxes, and macropods, depending on site. from 1997 to 1999, sera (n=1706) were collected from dogs, cats, ...200717360861
a curious coincidence: mosquito biodiversity and the limits of the japanese encephalitis virus in australasia.the mosquito culex annulirostris skuse (diptera: culicidae) is the major vector of endemic arboviruses in australia and is also responsible for the establishment of the japanese encephalitis virus (jev) in southern papua new guinea (png) as well as its incursions into northern australia. papua new guinea and mainland australia are separated by a small stretch of water, the torres strait, and its islands. while there has been regular jev activity on these islands, jev has not established on mainl ...200717598922
a mosquito predator survey in townsville, australia, and an assessment of diplonychus sp. and anisops sp. predatorial capacity against culex annulirostris mosquito immatures.a twelve-month survey for mosquito predators was conducted in townsville, queensland, australia, which is located in the arid tropics. the survey revealed the presence of five predaceous insects but only anisops sp. (backswimmers) and diplonychus sp. were common. predatorial capacity and factors influencing this capacity were then assessed for adult anisops sp. and adult and nymph stages of diplonychus sp. against culex annulirostris mosquito immatures under laboratory conditions. predatorial ca ...200717633421
expectoration of flaviviruses during sugar feeding by mosquitoes (diptera: culicidae).biological transmission of arboviruses to a vertebrate host occurs when virions are expelled along with saliva during blood feeding by a hematophagous arthropod. we undertook experiments to determine whether mosquitoes expectorate flaviviruses in their saliva while sugar feeding. batches of culex annulirostris skuse and culex gelidus theobald (diptera: culicidae) were orally infected with japanese encephalitis (family flaviviridae, genus flavivirus, jev), kunjin (family flaviviridae, genus flavi ...200717915518
is the extract from the plant catmint (nepeta cataria) repellent to mosquitoes in australia?the repellency of nepeta cataria (catmint or catnip) was tested against aedes aegypti, ae. vigilax, culex annulirostris, and cx. quinquefasciatus, and compared with a blend of natural plant extracts and n,n-diethyl-3-methylbenzamide (deet) on human skin. the catmint and natural plant extract blend did not provide the same level of protection from biting mosquitoes as deet. there were significant differences in the level of protection provided by catmint to the 4 species of mosquito, with mean pr ...200717939520
experimental infection of aedes sollicitans and aedes taeniorhynchus with two chimeric sindbis/eastern equine encephalitis virus vaccine candidates.two chimeric vaccine candidates for eastern equine encephalitis virus (eeev) were developed by inserting the structural protein genes of either a north american (na) or south american (sa) eeev into a sindbis virus (sinv) backbone. to assess the effect of chimerization on mosquito infectivity, experimental infections of two potential north american bridge vectors of eeev, aedes sollicitans and ae. taeniorhynchus, were attempted. both species were susceptible to oral infection with all viruses af ...200818187790
genetic determinants of virulence in pathogenic lineage 2 west nile virus strains.we determined complete genome sequences of lineage 2 west nile virus (wnv) strains isolated from patients in south africa who had mild or severe wnv infections. these strains had previously been shown to produce either highly or less neuroinvasive infection and induced genes similar to corresponding highly or less neuroinvasive lineage 1 strains in mice. phylogenetic and amino acid comparison of highly and less neuroinvasive lineage 2 strains demonstrated that the nonstructural genes, especially ...200818258114
house mouse abundance and ross river virus notifications in victoria, australia.the number of emerging and re-emerging infectious diseases is increasing. as such, understanding the fundamental ecology of infectious disease is critical. short-lived highly fecund amplification hosts are implicated to influence disease prevalence, but few empirical examples exist. we examined the relationship between mouse (mus musculus) abundance and ross river virus (rrv) incidence in northwest victoria, australia.200818468469
predictive indicators for ross river virus infection in the darwin area of tropical northern australia, using long-term mosquito trapping describe the epidemiology of ross river virus (rrv) infection in the endemic darwin region of tropical northern australia and to develop a predictive model for rrv infections.200818482196
genetic variation of st. louis encephalitis louis encephalitis virus (slev) has been regularly isolated throughout the americas since 1933. previous phylogenetic studies involving 62 isolates have defined seven major lineages (i-vii), further divided into 14 clades. in this study, 28 strains isolated in texas in 1991 and 2001-2003, and three older, previously unsequenced strains from jamaica and california were sequenced over the envelope protein gene. the inclusion of these new sequences, and others published since 2001, has allowed ...200818632961
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 ...200818973445
domestic pigs and japanese encephalitis virus infection, determine whether relocating domestic pigs, the amplifying host of japanese encephalitis virus (jev), decreased the risk for jev transmission to humans in northern australia, we collected mosquitoes for virus detection. detection of jev in mosquitoes after pig relocation indicates that pig relocation did not eliminate jev risk.200818976557
size alters susceptibility of vectors to dengue virus infection and dissemination.the size of arthropod vectors may affect their ability to transmit pathogens. here we test the hypothesis that body size alters the susceptibility of aedes aegypti and aedes albopictus mosquitoes to dengue virus (denv) infection and subsequent dissemination throughout the body of the mosquito. after feeding on blood containing known quantities of virus, smaller-sized females were significantly more likely to become infected and to disseminate virus than larger individuals. the effects of size we ...200818981505
resolving genetic diversity in australasian culex mosquitoes: incongruence between the mitochondrial cytochrome c oxidase i and nuclear acetylcholine esterase 2.insects that vector pathogens are under constant surveillance in australasia although the repertoire of genetic markers to distinguish what are often cryptic mosquito species remains limited. we present a comparative assessment of the second exon-intron region of the acetylcholine esterase 2 gene (ace-2) and the mitochondrial dna cytochrome c oxidase i (coi) using two closely related australasia mosquitoes culex annulirostris and culex palpalis. the coi revealed eight divergent lineages of which ...200919059488
climate variability, social and environmental factors, and ross river virus transmission: research development and future research needs.arbovirus diseases have emerged as a global public health concern. however, the impact of climatic, social, and environmental variability on the transmission of arbovirus diseases remains to be determined.200819079707
tahyna virus and human infection, 2006, tahyna virus was isolated from culex spp. mosquitoes collected in xinjiang, people's republic of china. in 2007, to determine whether this virus was infecting humans, we tested serum from febrile patients. we found immunoglobulin (ig) m and igg against the virus, which suggests human infection in this region.200919193280
genetic and epidemiological characterization of stretch lagoon orbivirus, a novel orbivirus isolated from culex and aedes mosquitoes in northern australia.stretch lagoon orbivirus (slov) was isolated in 2002 from pooled culex annulirostris mosquitoes collected at stretch lagoon, near the wolfe creek national park in the kimberley region of western australia. conventional serological tests were unable to identify the isolate, and electron microscopy indicated a virus of the genus orbivirus, family reoviridae. here, a cdna subtraction method was used to obtain approximately one-third of the viral genome, and further sequencing was performed to compl ...200919282430
changing patterns of west nile virus transmission: altered vector competence and host susceptibility.west nile virus (wnv) is a flavivirus (flaviviridae) transmitted between culex spp. mosquitoes and avian hosts. the virus has dramatically expanded its geographic range in the past ten years. increases in global commerce, climate change, ecological factors and the emergence of novel viral genotypes likely play significant roles in the emergence of this virus; however, the exact mechanism and relative importance of each is uncertain. previously wnv was primarily associated with febrile illness of ...200919406093
genomic sequence and phylogenetic analysis of culex flavivirus, an insect-specific flavivirus, isolated from culex pipiens (diptera: culicidae) in mosquitoes (diptera: culicidae) were collected in 2007 and tested for specific viruses, including west nile virus, as part of the ongoing arbovirus surveillance efforts in the state of iowa. a subset of these mosquitoes (6,061 individuals in 340 pools) was further tested by reverse transcription-polymerase chain reaction (rt-pcr) using flavivirus universal primers. of the 211 pools of culex pipiens (l.) tested, 50 were positive. one of 51 pools of culex tarsalis coquillet was also positive ...200919645300
laboratory and field evaluation of ss220 and deet against mosquitoes in queensland, australia.laboratory and field efficacy trials comparing deet (n,n-diethyl-3-methylbenzamide) and ss220 [(is, 2's)-2-methylpiperindinyl-3-cyclohexen-1-carboxamide] against mosquitoes in queensland, australia, were conducted. in the laboratory, both compounds provided between 150 and 195 min of protection against aedes aegypti and between 18 and 80 min of protection against anopheles farauti. in laboratory tests against culex annulirostris, 20% ss220 provided 3 h of protection and 20% deet provided >6 h of ...200919653499
transmission of japanese encephalitis virus from the black flying fox, pteropus alecto, to culex annulirostris mosquitoes, despite the absence of detectable determine the potential role of flying foxes in transmission cycles of japanese encephalitis virus (jev) in australia, we exposed pteropus alecto (megachiroptera: pteropididae) to jev via infected culex annulirostris mosquitoes or inoculation. no flying foxes developed symptoms consistent with jev infection. anti-jev igg antibodies developed in 6/10 flying foxes exposed to infected cx. annulirostris and in 5/5 inoculated flying foxes. low-level viremia was detected by real-time reverse transc ...200919706915
larval environmental temperature and the susceptibility of aedes albopictus skuse (diptera: culicidae) to chikungunya virus.a key feature in the recent widespread epidemic of the mosquito-borne alphavirus chikungunya virus (chikv) was the important role of aedes albopictus, formerly regarded as a secondary vector, compared to the presumed primary vector aedes aegypti. ae. albopictus, a container-inhabiting mosquito, is an invasive species that occurs over a wide geographic range spanning tropical and temperate latitudes. in this study we examine the effects of a broad range of larval rearing temperatures on chikv inf ...201019725768
determination of mosquito (diptera: culicidae) bloodmeal sources in western australia: implications for arbovirus transmission.a double-antibody enzyme-linked immunosorbent assay was used to determine the bloodmeal sources of adult mosquitoes (diptera: culicidae) collected in encephalitis vector surveillance mosquito traps in western australia between may 1993 and august 2004. in total, 2,606 blood-fed mosquitoes, representing 29 mosquito species, were tested, and 81.7% reacted with one or more of the primary antibodies. aedes camptorhynchus (thomson) and culex annulirostris skuse were the most common species tested, ma ...200919769051
are commercially available essential oils from australian native plants repellent to mosquitoes?while the use of topical insect repellents, particularly those containing synthetic active ingredients such as deet (n,n-diethyl-3-methylbenzamide), are a mainstay in personal protection strategies emphasized in public health messages, there is a growing demand in the community for alternative repellents, particularly those of botanical origin and thus deemed to be "natural." this study evaluated the repellency of essential oils from 11 australian native plants in 5% v/v formulations against aed ...200919852219
comparative field evaluation of repellent formulations containing deet and ir3535 against mosquitoes in queensland, australia.field trials comparing repellent formulations containing ir3535 (ethyl butylacetylaminopropionate) and deet (n,n-diethyl-3-methylbenzamide) against mosquitoes in queensland, australia, were conducted. two repellents were compared: avon bug guard, containing 7.5% ir3535; and australian defense force (adf) deet, containing 35% deet in a gel. two tests were conducted, one in february-march 2006, and the second in february 2007. in the 1st test, the predominant mosquito species collected were manson ...200920099600
difference in mosquito species (diptera: culicidae) and the transmission of ross river virus between coastline and inland areas in brisbane, australia.this study examined the distribution of major mosquito species and their roles in the transmission of ross river virus (rrv) infection for coastline and inland areas in brisbane, australia (27 degrees 28' s, 153 degrees 2' e). we obtained data on the monthly counts of rrv cases in brisbane between november 1998 and december 2001 by statistical local areas from the queensland department of health and the monthly mosquito abundance from the brisbane city council. correlation analysis was used to a ...201020146843
blood feeding patterns of mosquitoes: random or structured?abstract:201020205866
exploiting mosquito sugar feeding to detect mosquito-borne pathogens.arthropod-borne viruses (arboviruses) represent a global public health problem, with dengue viruses causing millions of infections annually, while emerging arboviruses, such as west nile, japanese encephalitis, and chikungunya viruses have dramatically expanded their geographical ranges. surveillance of arboviruses provides vital data regarding their prevalence and distribution that may be utilized for biosecurity measures and the implementation of disease control strategies. however, current su ...201020534559
differential impact of west nile virus on california birds.the strain of west nile virus (wnv) currently epidemic in north america contains a genetic mutation elevating its virulence in birds, especially species in the family corvidae. although dead american crows (corvus brachyrhynchos) have been the hallmark of the epidemic, the overall impact of wnv on north america's avifauna remains poorly understood and has not been addressed thoroughly in california. here, we evaluate variation by species in the effect of wnv on california birds from 2004 to 2007 ...200920589226
arboviral encephalitides: transmission, emergence, and pathogenesis.arthropod-borne viruses (arboviruses) are of paramount concern as a group of pathogens at the forefront of emerging and re-emerging diseases. although some arboviral infections are asymptomatic or present with a mild influenza-like illness, many are important human and veterinary pathogens causing serious illness ranging from rash and arthritis to encephalitis and hemorrhagic fever. here, we discuss arboviruses from diverse families (flaviviruses, alphaviruses, and the bunyaviridae) that are cau ...201020652430
bayesian spatiotemporal analysis of socio-ecologic drivers of ross river virus transmission in queensland, australia.this study aims to examine the impact of socio-ecologic factors on the transmission of ross river virus (rrv) infection and to identify areas prone to social and ecologic-driven epidemics in queensland, australia. we used a bayesian spatiotemporal conditional autoregressive model to quantify the relationship between monthly variation of rrv incidence and socio-ecologic factors and to determine spatiotemporal patterns. our results show that the average increase in monthly rrv incidence was 2.4% ( ...201020810846
environmental monitoring to enhance comprehension and control of infectious a world of emerging and resurging infectious diseases, dominated by zoonoses, environmental monitoring plays a vital role in our understanding their dynamics and their spillover to humans. here, we critically review the ecology, epidemiology and need for monitoring of a variety of directly transmitted (sin nombre virus, avian influenza) and vector-borne (ross river virus, west nile virus, lyme disease, anaplasmosis and babesiosis) zoonoses. we focus on the valuable role that existing monitori ...201020957286
application of satellite precipitation data to analyse and model arbovirus activity in the tropics.murray valley encephalitis virus (mvev) is a mosquito-borne flavivirus (flaviviridae: flavivirus) which is closely related to japanese encephalitis virus, west nile virus and st. louis encephalitis virus. mvev is enzootic in northern australia and papua new guinea and epizootic in other parts of australia. activity of mvev in western australia (wa) is monitored by detection of seroconversions in flocks of sentinel chickens at selected sample sites throughout wa. rainfall is a major environmental ...201121255449
type iii ifns in pteropid bats: differential expression patterns provide evidence for distinct roles in antiviral immunity.bats are known to harbor a number of emerging and re-emerging zoonotic viruses, many of which are highly pathogenic in other mammals but result in no clinical symptoms in bats. the ability of bats to coexist with viruses may be the result of rapid control of viral replication early in the immune response. ifns provide the first line of defense against viral infection in vertebrates. type iii ifns (ifn-?s) are a recently identified ifn family that share similar antiviral activities with type i if ...201121278349
the current status and future directions of myxoma virus, a master in immune evasion.abstract: myxoma virus (myxv) gained importance throughout the twentieth century because of the use of the highly virulent standard laboratory strain (sls) by the australian government in the attempt to control the feral australian population of oryctolagus cuniculus (european rabbit) and the subsequent illegal release of myxv in europe. in the european rabbit, myxv causes a disease with an exceedingly high mortality rate, named myxomatosis, which is passively transmitted by biting arthropod vec ...201121658227
the 6a resolution cryo-em barmah forest virus structure shows detailed transmembrane proteins architecture and interactions.barmah forest virus (bfv) is a mosquito-borne alphavirus that infects humans. a 6å resolution cryo-electron microscopy three-dimensional structure of bfv exhibits a typical alphavirus organization with rna-containing nucleocapsid surrounded by a bilipid membrane anchored with the surface proteins e1 and e2. the map allows details of the transmembrane regions of e1 and e2 to be seen. the c-terminal end of the e2 transmembrane helix binds to the capsid protein. following the e2 transmembrane helix ...201121752915
entomological study of chikungunya infections in the state of kelantan, malaysia.chikungunya infection has become a public health threat in malaysia since the 2008 nationwide outbreaks. aedes albopictus skuse has been identified as the chikungunya vector in johor state during the outbreaks. in 2009, several outbreaks had been reported in the state of kelantan. entomological studies were conducted in kelantan in four districts, namely jeli, tumpat, pasir mas and tanah merah to identify the vector responsible for the virus transmission.201121727669
Umatilla virus genome sequencing and phylogenetic analysis: identification of stretch lagoon orbivirus as a new member of the Umatilla virus species.The genus Orbivirus, family Reoviridae, includes 22 species of viruses with genomes composed of ten segments of linear dsRNA that are transmitted between their vertebrate hosts by insects or ticks, or with no identified vectors. Full-genome sequence data are available for representative isolates of the insect borne mammalian orbiviruses (including bluetongue virus), as well as a tick borne avian orbivirus (Great Island virus). However, no sequence data are as yet available for the mosquito borne ...201121897849
west nile virus (kunjin subtype) disease in the northern territory of australia--a case of encephalitis and review of all reported cases.west nile virus kunjin subtype (wnv/kunv) is enzootic across the tropical north of australia, with epizootic spread into other jurisdictions. the clinical spectrum of illness in humans is poorly described. we report a clinical case of wnv/kunv encephalitis and performed a retrospective chart audit of all cases of wnv/kunv notified in the northern territory from 1992 to 2010. thirteen cases of wnv/kunv disease were identified; case notes were available for 10 of these presentations. six of these ...201122049056
Habitat modification for mosquito control in the Ilparpa Swamp, Northern Territory, Australia.Habitat modification is an established method of effective long-term mosquito management, particularly in salt-marsh environments. It is especially pertinent when mosquitoes are known vectors of life-threatening disease and their larval breeding habitat is in close proximity to residential areas. The Ilparpa Swamp is located less than 10 km from Alice Springs, Northern Territory. Wet season rainfall, often followed by effluent discharges to the swamp from the adjacent sewage treatment plant, cre ...201122129400
spatio-temporal patterns of barmah forest virus disease in queensland, australia.barmah forest virus (bfv) disease is a common and wide-spread mosquito-borne disease in australia. this study investigated the spatio-temporal patterns of bfv disease in queensland, australia using geographical information system (gis) tools and geostatistical analysis.201122022430
Globalization, land use, and the invasion of West Nile virus.Many invasive species that have been spread through the globalization of trade and travel are pathogens. A paradigmatic case is the introduction of West Nile virus (WNV) into North America in 1999. A decade of research on the ecology and evolution of WNV includes three findings that provide insight into the outcome of future pathogen introductions. First, WNV transmission in North America is highest in urbanized and agricultural habitats, in part because the hosts and vectors of WNV are abundant ...201122021850
rapid molecular detection methods for arboviruses of livestock of importance to northern europe.arthropod-borne viruses (arboviruses) have been responsible for some of the most explosive epidemics of emerging infectious diseases over the past decade. their impact on both human and livestock populations has been dramatic. the early detection either through surveillance or diagnosis of virus will be a critical feature in responding and resolving the emergence of such epidemics in the future. although some of the most important emerging arboviruses are human pathogens, this paper aims to high ...201222219660
surveillance should be strengthened to improve epidemiological understandings of mosquito-borne barmah forest virus infection.barmah forest virus (bfv) is a mosquito-borne virus causing epidemic polyarthritis in australia. this study used case follow-up of cases from the surveillance system to demonstrate that routinely collected bfv notification data were an unreliable indicator of the true location of exposure.201223908926
potential changes in disease patterns and pharmaceutical use in response to climate climate change alters environmental conditions, the incidence and global patterns of human diseases are changing. these modifications to disease profiles and the effects upon human pharmaceutical usage are discussed. climate-related environmental changes are associated with a rise in the incidence of chronic diseases already prevalent in the northern hemisphere, for example, cardiovascular disease and mental illness, leading to greater use of associated heavily used western medications. suffe ...201323909463
mosquito communities and disease risk influenced by land use change and seasonality in the australian tropics.anthropogenic land use changes have contributed considerably to the rise of emerging and re-emerging mosquito-borne diseases. these diseases appear to be increasing as a result of the novel juxtapositions of habitats and species that can result in new interchanges of vectors, diseases and hosts. we studied whether the mosquito community structure varied between habitats and seasons and whether known disease vectors displayed habitat preferences in tropical australia.201627388293
global emergence of alphaviruses that cause arthritis in humans.arthropod-borne viruses (arboviruses) may cause severe emerging and re-emerging infectious diseases, which pose a significant threat to human and animal health in the world today. these infectious diseases range from mild febrile illnesses, arthritis, and encephalitis to haemorrhagic fevers. it is postulated that certain environmental factors, vector competence, and host susceptibility have a major impact on the ecology of arboviral diseases. presently, there is a great interest in the emergence ...201526689654
development and field evaluation of the sentinel mosquito arbovirus capture kit (smack).although sentinel animals are used successfully throughout the world to monitor arbovirus activity, ethical considerations and cross-reactions in serological assays highlight the importance of developing viable alternatives. here we outline the development of a passive sentinel mosquito arbovirus capture kit (smack) that allows for the detection of arboviruses on honey-baited nucleic acid preservation cards (flinders technology associates; fta®) and has a similar trap efficacy as standard light ...201526444264
enhanced arbovirus surveillance with deep sequencing: identification of novel rhabdoviruses and bunyaviruses in australian mosquitoes.viral metagenomics characterizes known and identifies unknown viruses based on sequence similarities to any previously sequenced viral genomes. a metagenomics approach was used to identify virus sequences in australian mosquitoes causing cytopathic effects in inoculated mammalian cell cultures. sequence comparisons revealed strains of liao ning virus (reovirus, seadornavirus), previously detected only in china, livestock-infecting stretch lagoon virus (reovirus, orbivirus), two novel dimarhabdov ...201324314645
mosquito consumption by insectivorous bats: does size matter?insectivorous bats have often been touted as biological control for mosquito populations. however, mosquitoes generally represent only a small proportion of bat diet. given the small size of mosquitoes, restrictions imposed on prey detectability by low frequency echolocation, and variable field metabolic rates (fmr), mosquitoes may not be available to or profitable for all bats. this study investigated whether consumption of mosquitoes was influenced by bat size, which is negatively correlated w ...201324130851
foraging ranges of insectivorous bats shift relative to changes in mosquito abundance.the need to develop effective management strategies for insectivorous bat populations requires an understanding of factors influencing habitat use. availability of pest prey, such as mosquitoes is likely to be one such factor. to assess whether this is the case, we radio-tracked vespadelus vulturnus thomas (little forest bat), a predator of aedes vigilax skuse (saltmarsh mosquito), in saltmarsh and adjacent coastal swamp forest during periods of high and low ae. vigilax abundance. when mosquito ...201323667699
a tyrosine-to-histidine switch at position 18 of the ross river virus e2 glycoprotein is a determinant of virus fitness in disparate hosts.arthritogenic alphaviruses are human pathogens maintained in nature through alternating replication in vertebrates and mosquitoes. using chimeric viruses, we previously reported that replacement of the pe2 coding region of the t48 strain of ross river virus (rrv-t48) with that from the attenuated dc5692 strain, which differ by 7 amino acids, resulted in an attenuated disease phenotype in a mouse model of rrv-induced rheumatic disease. here, we demonstrate that introduction of one of these amino ...201323514884
wolbachia biocontrol strategies for arboviral diseases and the potential influence of resident wolbachia strains in mosquitoes.arboviruses transmitted by mosquitoes are a major cause of human disease worldwide. the absence of vaccines and effective vector control strategies has resulted in the need for novel mosquito control strategies. the endosymbiotic bacterium wolbachia has been proposed to form the basis for an effective mosquito biocontrol strategy. resident strains of wolbachia inhibit viral replication in drosophila fruit flies and induce a reproductive phenotype known as cytoplasmic incompatibility that allows ...201626925368
review of insecticide resistance and behavioral avoidance of vectors of human diseases in thailand.physiological resistance and behavioral responses of mosquito vectors to insecticides are critical aspects of the chemical-based disease control equation. the complex interaction between lethal, sub-lethal and excitation/repellent ('excito-repellent') properties of chemicals is typically overlooked in vector management and control programs. the development of "physiological" resistance, metabolic and/or target site modifications, to insecticides has been well documented in many insect groups and ...201324294938
the effect of multiple vectors on arbovirus transmission.many mosquito-borne arboviruses have more than one competent vector. these vectors may or may not overlap in space and time, and may interact differently with vertebrate hosts. the presence of multiple vectors for a particular virus at one location over time will influence the epidemiology of the system, and could be important in the design of intervention strategies to protect particular hosts. a simulation model previously developed for west nile and st. louis encephalitis viruses and culex ni ...023741205
virulence and evolution of west nile virus, australia, 1960-2012.worldwide, west nile virus (wnv) causes encephalitis in humans, horses, and birds. the kunjin strain of wnv (wnvkun) is endemic to northern australia, but infections are usually asymptomatic. in 2011, an unprecedented outbreak of equine encephalitis occurred in southeastern australia; most of the ≈900 reported cases were attributed to a newly emerged wnvkun strain. to investigate the origins of this virus, we performed genetic analysis and in vitro and in vivo studies of 13 wnvkun isolates colle ...027433830
the insect-specific palm creek virus modulates west nile virus infection in and transmission by australian mosquitoes.insect-specific viruses do not replicate in vertebrate cells, but persist in mosquito populations and are highly prevalent in nature. these viruses may naturally regulate the transmission of pathogenic vertebrate-infecting arboviruses in co-infected mosquitoes. following the isolation of the first australian insect-specific flavivirus (isf), palm creek virus (pcv), we investigated routes of infection and transmission of this virus in key australian arbovirus vectors and its impact on replication ...201627457250
genetic characterization of archived bunyaviruses and their potential for emergence in better understand the diversity of bunyaviruses and their circulation in australia, we sequenced 5 viruses (gan gan, trubanaman, kowanyama, yacaaba, and taggert) isolated and serologically identified 4 decades ago as members of the family bunyaviridae. gan gan and trubanaman viruses almost perfectly matched 2 recently isolated, purportedly novel viruses, salt ash and murrumbidgee viruses, respectively. kowanyama and yacaaba viruses were identified as being related to members of a large clade ...027088588
larval temperature-food effects on adult mosquito infection and vertical transmission of dengue-1 virus.temperature-food interactions in the larval environment can affect life history and population growth of container mosquitoes aedes aegypti (l.) and aedes albopictus skuse, the primary vectors of chikungunya and dengue viruses. we used ae. aegypti, ae. albopictus, and dengue-1 virus (denv-1) from florida to investigate whether larval rearing temperature can alter the effects of larval food levels on ae. aegypti and ae. albopictus life history and denv-1 infection and vertical transmission. altho ...201526489999
ross river virus: many vectors and unusual hosts make for an unpredictable pathogen. 201526335937
role of enhanced vector transmission of a new west nile virus strain in an outbreak of equine disease in australia in 2011, a variant of west nile virus kunjin strain (wnvkun) caused an unprecedented epidemic of neurological disease in horses in southeast australia, resulting in almost 1,000 cases and a 9% fatality rate. we investigated whether increased fitness of the virus in the primary vector, culex annulirostris, and another potential vector, culex australicus, contributed to the widespread nature of the outbreak.201425499981
epidemiologic patterns of ross river virus disease in queensland, australia, 2001-2011.ross river virus (rrv) infection is a debilitating disease that has a significant impact on population health, economic productivity, and tourism in australia. this study examined epidemiologic patterns of rrv disease in queensland, australia, during january 2001-december 2011 at a statistical local area level. spatio-temporal analyses were used to identify the patterns of the disease distribution over time stratified by age, sex, and space. the results show that the mean annual incidence was 54 ...201424799374
a new insect-specific flavivirus from northern australia suppresses replication of west nile virus and murray valley encephalitis virus in co-infected mosquito cells.recent reports of a novel group of flaviviruses that replicate only in mosquitoes and appear to spread through insect populations via vertical transmission have emerged from around the globe. to date, there is no information on the presence or prevalence of these insect-specific flaviviruses (isfs) in australian mosquito species. to assess whether such viruses occur locally, we used reverse transcription-polymerase chain reaction (rt-pcr) and flavivirus universal primers that are specific to the ...201323460804
the contribution of rodent models to the pathological assessment of flaviviral infections of the central nervous system.members of the genus flavivirus are responsible for a spectrum of important neurological syndromes in humans and animals. rodent models have been used extensively to model flavivirus neurological disease, to discover host-pathogen interactions that influence disease outcome, and as surrogates to determine the efficacy and safety of vaccines and therapeutics. in this review, we discuss the current understanding of flavivirus neuroinvasive disease and outline the host, viral and experimental facto ...201222592957
a glance at subgenomic flavivirus rnas and micrornas in flavivirus infections.the family flaviviridae comprises a wide variety of viruses that are distributed worldwide, some of which are associated with high rates of morbidity and mortality. there are neither vaccines nor antivirals for most flavivirus infections, reinforcing the importance of research on different aspects of the viral life cycle. during infection, cytoplasmic accumulation of rna fragments mainly originating from the 3' utrs, which have been designated subgenomic flavivirus rnas (sfrnas), has been detect ...201627233361
new insights into flavivirus evolution, taxonomy and biogeographic history, extended by analysis of canonical and alternative coding generate the most diverse phylogenetic dataset for the flaviviruses to date, we determined the genomic sequences and phylogenetic relationships of 14 flaviviruses, of which 10 are primarily associated with culex spp. mosquitoes. we analyze these data, in conjunction with a comprehensive collection of flavivirus genomes, to characterize flavivirus evolutionary and biogeographic history in unprecedented detail and breadth. based on the presumed introduction of yellow fever virus into the americ ...201525719412
programmed ribosomal frameshift alters expression of west nile virus genes and facilitates virus replication in birds and mosquitoes.west nile virus (wnv) is a human pathogen of significant medical importance with close to 40,000 cases of encephalitis and more than 1,600 deaths reported in the us alone since its first emergence in new york in 1999. previous studies identified a motif in the beginning of non-structural gene ns2a of encephalitic flaviviruses including wnv which induces programmed -1 ribosomal frameshift (prf) resulting in production of an additional ns protein ns1'. we have previously demonstrated that mutant w ...201425375107
comparison of genotypes i and iii in japanese encephalitis virus reveals distinct differences in their genetic and host diversity.japanese encephalitis (je) is an arthropod-borne disease associated with the majority of viral encephalitis cases in the asia-pacific region. the causative agent, japanese encephalitis virus (jev), has been phylogenetically divided into five genotypes. recent surveillance data indicate that genotype i (gi) is gradually replacing genotype iii (giii) as the dominant genotype. to investigate the mechanism behind the genotype shift and the potential consequences in terms of vaccine efficacy, human c ...201425056890
the spatio-temporal distribution of japanese encephalitis cases in different age groups in mainland china, 2004 - 2014.japanese encephalitis (je) is very prevalent in china, but the incidence of je among children has been greatly reduced by extensive promotion of vaccinations. the incidence of je among adults, however, has increased in some parts of china.201627050414
climate change impacts on west nile virus transmission in a global context.west nile virus (wnv), the most widely distributed virus of the encephalitic flaviviruses, is a vector-borne pathogen of global importance. the transmission cycle exists in rural and urban areas where the virus infects birds, humans, horses and other mammals. multiple factors impact the transmission and distribution of wnv, related to the dynamics and interactions between pathogen, vector, vertebrate hosts and environment. hence, among other drivers, weather conditions have direct and indirect i ...025688020
ecological niche modeling to estimate the distribution of japanese encephalitis virus in asia.culex tritaeniorhynchus is the primary vector of japanese encephalitis virus (jev), a leading cause of encephalitis in asia. jev is transmitted in an enzootic cycle involving large wading birds as the reservoirs and swine as amplifying hosts. the development of a jev vaccine reduced the number of je cases in regions with comprehensive childhood vaccination programs, such as in japan and the republic of korea. however, the lack of vaccine programs or insufficient coverage of populations in other ...201222724030
rainfall and sentinel chicken seroconversions predict human cases of murray valley encephalitis in the north of western australia.murray valley encephalitis virus (mvev) is a flavivirus that occurs in australia and new guinea. while clinical cases are uncommon, mvev can cause severe encephalitis with high mortality. sentinel chicken surveillance is used at many sites around australia to provide an early warning system for risk of human infection in areas that have low population density and geographical remoteness. mvev in western australia occurs in areas of low population density and geographical remoteness, resulting in ...201425490948
natural exposure of horses to mosquito-borne flaviviruses in south-east queensland, 2011 an unprecedented epidemic of equine encephalitis occurred in south-eastern (se) australia following heavy rainfall and severe flooding in the preceding 2-4 months. less than 6% of the documented cases occurred in queensland, prompting the question of pre-existing immunity in queensland horses. a small-scale serological survey was conducted on horses residing in one of the severely flood-affected areas of se-queensland. using a flavivirus-specific blocking-elisa we found that 63% (39/62) ...201324048209
ecology of west nile virus in north america.the introduction, dispersal and establishment of west nile virus in north america were reviewed, focusing on factors that may have enhanced receptivity and enabled the invasion process. the overwintering persistence of this tropical virus within temperate latitudes was unexpected, but was key in the transition from invasion to endemic establishment. the cascade of temporal events allowing sporadic amplification to outbreak levels was discussed within a future perspective.201324008376
characterization of virulent west nile virus kunjin strain, australia, determine the cause of an unprecedented outbreak of encephalitis among horses in new south wales, australia, in 2011, we performed genomic sequencing of viruses isolated from affected horses and mosquitoes. results showed that most of the cases were caused by a variant west nile virus (wnv) strain, wnv(nsw2011), that is most closely related to wnv kunjin (wnv(kun)), the indigenous wnv strain in australia. studies in mouse models for wnv pathogenesis showed that wnv(nsw2011) is substantially m ...022516173
cullin4 is pro-viral during west nile virus infection of culex mosquitoes.although mosquitoes serve as vectors of many pathogens of public health importance, their response to viral infection is poorly understood. it also remains to be investigated whether viruses deploy some mechanism to be able to overcome this immune response. here, we have used an rna-seq approach to identify differentially regulated genes in culex quinquefasciatus cells following west nile virus (wnv) infection, identifying 265 transcripts from various cellular pathways that were either upregulat ...201526325027
complete genome sequences of the prototype isolates of genotypes 2, 3, and 4 of murray valley encephalitis virus.murray valley encephalitis virus (mvev) (flaviviridae family, flavivirus genus), a mosquito-borne pathogen of humans and horses, is endemic to the australasian region. we report here the complete genomes of the prototype strains of mvev genotypes 2, 3, and 4.201424948762
a spatial and temporal analysis of japanese encephalitis in mainland china, 1963-1975: a period without japanese encephalitis vaccination.more than a million japanese encephalitis (je) cases occurred in mainland china from the 1960s to 1970s without vaccine interventions. the aim of this study is to analyze the spatial and temporal pattern of je cases reported in mainland china from 1965 to 1973 in the absence of je vaccination, and to discuss the impacts of climatic and geographical factors on je during that period. thus, the data of reported je cases at provincial level and monthly precipitation and monthly mean temperature from ...201424911168
the changing epidemiology of murray valley encephalitis in australia: the 2011 outbreak and a review of the literature.murray valley encephalitis virus (mvev) is the most serious of the endemic arboviruses in australia. it was responsible for six known large outbreaks of encephalitis in south-eastern australia in the 1900s, with the last comprising 58 cases in 1974. since then mvev clinical cases have been largely confined to the western and central parts of northern australia. in 2011, high-level mvev activity occurred in south-eastern australia for the first time since 1974, accompanied by unusually heavy seas ...201424466360
regional impact of climate on japanese encephalitis in areas located near the three gorges this study, we aim to identify key climatic factors that are associated with the transmission of japanese encephalitis virus in areas located near the three gorges dam, between 1997 and 2008.201424404159
the west nile virus-like flavivirus koutango is highly virulent in mice due to delayed viral clearance and the induction of a poor neutralizing antibody response.the mosquito-borne west nile virus (wnv) is responsible for outbreaks of viral encephalitis in humans, horses, and birds, with particularly virulent strains causing recent outbreaks of disease in eastern europe, the middle east, north america, and australia. previous studies have phylogenetically separated wnv strains into two main genetic lineages (i and ii) containing virulent strains associated with neurological disease. several wnv-like strains clustering outside these lineages have been ide ...201424942584
a bayesian belief network for murray valley encephalitis virus risk assessment in western australia.murray valley encephalitis virus (mvev) is a clinically important virus in australia responsible for a number of epidemics over the past century. since there is no vaccine for mvev, other preventive health measures to curtail its spread must be considered, including the development of predictive risk models and maps to help direct public health interventions. this article aims to support these approaches by presenting a model for assessing mvev risk in western australia (wa).201626823368
recent weather extremes and impacts on agricultural production and vector-borne disease outbreak patterns.we document significant worldwide weather anomalies that affected agriculture and vector-borne disease outbreaks during the 2010-2012 period. we utilized 2000-2012 vegetation index and land surface temperature data from nasa's satellite-based moderate resolution imaging spectroradiometer (modis) to map the magnitude and extent of these anomalies for diverse regions including the continental united states, russia, east africa, southern africa, and australia. we demonstrate that shifts in temperat ...201424658301
seasonal drivers of the epidemiology of arthropod-borne viruses in australia.arthropod-borne viruses are a major cause of emerging disease with significant public health and economic impacts. however, the factors that determine their activity and seasonality are not well understood. in australia, a network of sentinel cattle herds is used to monitor the distribution of several such viruses and to define virus-free regions. herein, we utilize these serological data to describe the seasonality, and its drivers, of three economically important animal arboviruses: bluetongue ...201425412443
environmental predictors of west nile fever risk in europe.west nile virus (wnv) is a mosquito-borne pathogen of global public health importance. transmission of wnv is determined by abiotic and biotic factors. the objective of this study was to examine environmental variables as predictors of wnv risk in europe and neighboring countries, considering the anomalies of remotely sensed water and vegetation indices and of temperature at the locations of west nile fever (wnf) outbreaks reported in humans between 2002 and 2013.201424986363
a new species of mesonivirus from the northern territory, we describe casuarina virus (casv), a new virus in the family mesoniviridae. this is the first report of a mesonivirus in australia, which extends the geographical range of this virus family to 3 continents. the virus was isolated in 2010 from coquillettidia xanthogaster mosquitoes during surveillance in the suburbs of darwin, the capital of the northern territory. cryo-electron microscopy of the casv virions revealed spherical particles of 65 nm in size with large club-shaped projections o ...201424670468
a new orbivirus isolated from mosquitoes in north-western australia shows antigenic and genetic similarity to corriparta virus but does not replicate in vertebrate cells.the discovery and characterisation of new mosquito-borne viruses provides valuable information on the biodiversity of vector-borne viruses and important insights into their evolution. in this study, a broad-spectrum virus screening system, based on the detection of long double-stranded rna in inoculated cell cultures, was used to investigate the presence of novel viruses in mosquito populations of northern australia. we detected and isolated a new virus (tentatively named parry's lagoon virus, p ...201627213426
distribution of mosquito larvae on kosrae island, kosrae state, the federated states of micronesia.surveys of mosquito larvae were carried out in six areas of kosrae island, kosrae state, the federated states of micronesia in december 2009 and june 2012. a total of 962 larvae of six species were collected from 106 natural and artificial habitats. they were identified as aedes aegypti, ae. albopictus, ae. marshallensis, culex quinquefasciatus, cx. annulirostris, and cx. kusaiensis. this is the first report from kosrae island for three of these species-ae. marshallensis, cx. quinquefasciatus, a ...201324478593
complete coding sequences of three members of the kokobera group of flaviviruses.the kokobera group of flaviviruses circulates in australia and papua, new guinea, and has been associated with occasional human polyarticular disease. to facilitate future studies to identify virulence determinants, the complete coding regions of the stratford virus, and isolates of the bainyik virus and torres virus were obtained.201425237018
assessment of local mosquito species incriminates aedes aegypti as the potential vector of zika virus in australia.within the last 10 years zika virus (zikv) has caused unprecedented epidemics of human disease in the nations and territories of the western pacific and south america, and continues to escalate in both endemic and non-endemic regions. we evaluated the vector competence of australian mosquitoes for zikv to assess their potential role in virus transmission.201627643685
commensal viruses of mosquitoes: host restriction, transmission, and interaction with arboviral pathogens.recent advances in virus detection strategies and deep sequencing technologies have enabled the identification of a multitude of new viruses that persistently infect mosquitoes but do not infect vertebrates. these are usually referred to as insect-specific viruses (isvs). these novel viruses have generated considerable interest in their modes of transmission, persistence in mosquito populations, the mechanisms that restrict their host range to mosquitoes, and their interactions with pathogens tr ...201728096646
species interactions among larval mosquitoes: context dependence across habitat gradients.biotic interactions involving mosquito larvae are context dependent, with effects of interactions on populations altered by ecological conditions. relative impacts of competition and predation change across a gradient of habitat size and permanence. asymmetrical competition is common and ecological context changes competitive advantage, potentially facilitating landscape-level coexistence of competitors. predator effects on mosquito populations sometimes depend on habitat structure and on emerge ...019067629
using next-generation sequencing for dna barcoding: capturing allelic variation in its2.internal transcribed spacer 2 (its2) is a popular dna barcoding marker; however, in some animal species it is hypervariable and therefore difficult to sequence with traditional methods. with next-generation sequencing (ngs) it is possible to sequence all gene variants despite the presence of single nucleotide polymorphisms (snps), insertions/deletions (indels), homopolymeric regions, and microsatellites. our aim was to compare the performance of sanger sequencing and ngs amplicon sequencing in c ...201727799340
molecular identification of mosquitoes (diptera: culicidae) in southeastern australia.dna barcoding is a modern species identification technique that can be used to distinguish morphologically similar species, and is particularly useful when using small amounts of starting material from partial specimens or from immature stages. in order to use dna barcoding in a surveillance program, a database containing mosquito barcode sequences is required. this study obtained cytochrome oxidase i (coi) sequences for 113 morphologically identified specimens, representing 29 species, six trib ...201627217948
human and animal dirofilariasis: the emergence of a zoonotic mosaic.dirofilariasis represents a zoonotic mosaic, which includes two main filarial species (dirofilaria immitis and d. repens) that have adapted to canine, feline, and human hosts with distinct biological and clinical implications. at the same time, both d. immitis and d. repens are themselves hosts to symbiotic bacteria of the genus wolbachia, the study of which has resulted in a profound shift in the understanding of filarial biology, the mechanisms of the pathologies that they produce in their hos ...022763636
application of broad-spectrum resequencing microarray for genotyping rhabdoviruses.the rapid and accurate identification of pathogens is critical in the control of infectious disease. to this end, we analyzed the capacity for viral detection and identification of a newly described high-density resequencing microarray (rma), termed pathogenid, which was designed for multiple pathogen detection using database similarity searching. we focused on one of the largest and most diverse viral families described to date, the family rhabdoviridae. we demonstrate that this approach has th ...201020610710
a comparative analysis of three vector-borne diseases across australia using seasonal and meteorological models.ross river virus (rrv), barmah forest virus (bfv), and dengue are three common mosquito-borne diseases in australia that display notable seasonal patterns. although all three diseases have been modeled on localized scales, no previous study has used harmonic models to compare seasonality of mosquito-borne diseases on a continent-wide scale. we fit poisson harmonic regression models to surveillance data on rrv, bfv, and dengue (from 1993, 1995 and 1991, respectively, through 2015) incorporating s ...201728071683
a case report of mycoplasma wenyonii associated immune-mediated haemolytic anaemia in a dairy cow.a three year old, second lactation holstein dairy cow presented to the scottish centre for production animal health and food safety, glasgow university veterinary school in november 2014 with a history of post-calving vulval/vaginal bleeding nine days prior to presentation, followed by a sudden reduction in milk yield. subsequent investigations resulted in a diagnosis of immune-mediated haemolytic anaemia secondary to infection with mycoplasma wenyonii.201626807214
epidemiology and control of bovine ephemeral fever.bovine ephemeral fever (or 3-day sickness) is an acute febrile illness of cattle and water buffaloes. caused by an arthropod-borne rhabdovirus, bovine ephemeral fever virus (befv), the disease occurs seasonally over a vast expanse of the globe encompassing much of africa, the middle east, asia and australia. although mortality rates are typically low, infection prevalence and morbidity rates during outbreaks are often very high, causing serious economic impacts through loss of milk production, p ...201526511615
trypanosomes modify the behavior of their insect hosts: effects on locomotion and on the expression of a related a result of evolution, the biology of triatomines must have been significantly adapted to accommodate trypanosome infection in a complex network of vector-vertebrate-parasite interactions. arthropod-borne parasites have probably developed mechanisms, largely still unknown, to exploit the vector-vertebrate host interactions to ensure their transmission to suitable hosts. triatomines exhibit a strong negative phototaxis and nocturnal activity, believed to be important for insect survival agains ...201526291723
Displaying items 101 - 200 of 246