murray valley encephalitis acquired in western report a recent fatal case of encephalitis associated with evidence of murray valley encephalitis virus infection, only the second fatality from this infection in western australia.19911645843
larval diet and the vector competence of culex annulirostris (diptera: culicidae) for murray valley encephalitis virus.culex annulirostris skuse larvae were reared on two different amounts of powdered dog chow and yeast, low intake (2.8 micrograms/larva) and high intake (8.4 micrograms/larva), to produce adults with mean wing lengths of 3.25 and 3.7 mm, respectively. the resulting adults were fed different dosages of murray valley encephalitis virus and after 10 d extrinsic incubation at 28 degrees c, the infection rate, transmission rate, salivary gland, and body titers were determined. there were no significan ...19892552121
the vector competence of culex annulirostris, aedes sagax and aedes alboannulatus for murray valley encephalitis virus at different temperatures.culex annulirostris skuse, colonized from brisbane, queensland, and mildura, victoria, australia, were effective vectors of murray valley encephalitis virus at 20, 27 and 32-35 degrees c with full extrinsic incubation periods of 15, 10 and 4 days respectively. at 20 degrees c, 7-11 days post-infection, transmission by the mildura colony (0-20%) was less efficient than the brisbane colony (30-70%) but both were capable of 75-100% transmission after longer extrinsic incubation periods. discriminan ...19892562418
rearing temperature influences flavivirus vector competence of mosquitoes.culex annulirostris skuse mosquitoes (brisbane strain) were reared at 20 degrees c or 27 degrees c and the adult females were experimentally infected by feeding murray valley encephalitis virus (mve). they were then maintained (a) in the insectary at 20 degrees c, after rearing at either 20 degrees c or 27 degrees c; (b) at ambient outdoor temperatures, range 12.2-28.9 degrees c, mean 19.6 degrees c; or (c) at 27 degrees c after rearing at 27 degrees c. there was no significant difference in rat ...19892562419
experimental infection with murray valley encephalitis virus. pigs, cattle, sheep, dogs, rabbits, macropods and chickens.a total of 142 young animals including 10 domestic and 14 feral pigs, 12 hereford calves, 12 crossbred and 24 merino lambs, 11 dogs, 8 domestic and 16 feral rabbits, 14 grey kangaroos, 9 agile wallabies and 12 chickens was exposed to infection with 4 strains of murray valley encephalitis virus (mve), mainly using orally infected culex annulirostris mosquitoes. in terms of their viraemic response, the animals were grouped into high (grey kangaroos, rabbits), moderate (pigs, dogs, chickens) and lo ...19852990398
experimental infection with murray valley encephalitis virus: galahs, sulphur-crested cockatoos, corellas, black ducks and wild mice.orally infected culex annulirostris or intravenous injections were used to infect 10 galahs, 15 sulphur-crested cockatoos, 12 corellas, 4 black ducks and 10 wild mice with murray valley encephalitis (mve) virus. the birds produced moderate viraemias of titres of log 10(2.0)-10(6.0) suckling mouse intracerebral (smic) ld50/ml for durations of 1-9 d. however, the wild mice developed low grade viraemia for 1-4 d. recipient cx annulirostris feeding on viraemic birds sustained infection rates of 0-10 ...19853004402
[arboviral diseases in south-west pacific islands (author's transl)].islands of the south-west pacific area belong to the melanesian group, excepted niue, tonga, wallis and futuna which are polynesian. through new guinea, there is a geographic relation to the eastern part of australia, rich of 42 arbovirus types. dengue and ross river fever are the most important arboviral diseases in the region; both affect islanders after introduction of virus by travellers to localities where efficient vectors are present. dengue types 1, 2 and 4 were isolated from man and fro ...19816116150
isolation of murray valley encephalitis virus and other arboviruses in the ord river valley 1972-1976.this paper summarizes the isolation of arboviruses from mosquitoes collected in the ord valley between 1972 and 1976. a total of one hundred and ninety five strains of at least fifteen antigenically distinct viruses have been isolated. seven of these isolates appear to be "new' antigenic types, and several are undergoing further testing. these are three new rhabdoviruses (kununurra [or194], a virus provisionally named kimberley [or250] and or189 [provisionally named parry's creek]), three ungrou ...19816117274
variation in arbovirus infection rates in species of birds sampled in a serological survey during an encephalitis epidemic in the murray valley of south-eastern australia, february 1974.there was extensive and exuberant breeding of waterbirds before and during an epidemic of arboviral encephalitis in the murray valley of south eastern australia in 1974. as estimated by haemagglutination inhibition tests on 432 bird sera collected between 4th and 13th february, 1974, infection with murray valley encephalitis virus, kunjin virus and possibly other flaviviruses was concentrated in species of the order ciconiiformes (55% positive) and pelecaniformes (41%), compared with only 5% in ...19826299259
australian x disease, murray valley encephalitis and the french connection.epidemics of a severe encephalitis occurred in eastern australia between 1917 and 1925, in which over 280 cases were reported with a fatality rate of 68%. the disease had not been described previously and was called australian x disease. the next epidemic occurred in south-east australia in the summer of 1950-51. the disease was given its name of murray valley encephalitis as this was the area from which most cases were reported. a virus was isolated by eric french in victoria, and about the sam ...19958545982
mosquito (diptera: culicidae) dispersal: implications for the epidemiology of japanese and murray valley encephalitis viruses in hypothesis to explain the southern extension of japanese encephalitis (je) virus from papua new guinea into the torres strait islands in 1995 and to mainland australia in 1998 is the dispersal of infected mosquitoes, particularly culex annulirostris skuse from which je virus has been isolated repeatedly. to investigate whether this species disperses in this manner, mosquitoes were identified from 368 aerial kite trap collections operated at 50-310 m (altitude) at inland new south wales betwe ...200011126532
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 ...200314628944
murray valley encephalitis: a review of clinical features, diagnosis and treatment.murray valley encephalitis virus (mvev) is a mosquito-borne virus that is found across australia, papua new guinea and irian jaya. mvev is endemic to northern australia and causes occasional outbreaks across south-eastern australia. 2011 saw a dramatic increase in mvev activity in endemic regions and the re-emergence of mvev in south-eastern australia. this followed significant regional flooding and increased numbers of the main mosquito vector, culex annulirostris, and was evident from the wide ...201222432670
isolation of arboviruses from mosquitoes (diptera: culicidae) collected from the gulf plains region of northwest queensland, part of investigations into japanese encephalitis (je) virus and related flaviviruses in northern australia, 153,529 mosquitoes were collected and processed for virus isolation from the gulf plains region of northwest queensland. collections from within 30 km of each of the townships of croydon, normanton and karumba yielded 3,087 (2.0%), 66,009 (43.0%), and 84,433 (55.0%) mosquitoes, respectively, from which 16 viruses were isolated. four isolates of murray valley encephalitis (mve), two of ...200212349863
two possible mechanisms for survival and initiation of murray valley encephalitis virus activity in the kimberley region of western australia.two possible mechanisms are described for the initiation of murray valley encephalitis (mve) virus activity in arid, epizootic regions of tropical australia. virus isolations were made from mosquitoes trapped shortly after the first heavy wet season rains and flooding in the east kimberley, which followed approximately nine months of drought. a number of isolates of mve virus were obtained, including isolates from pools of blood-engorged culex annulirostris mosquitoes and from a single pool of m ...19957625542
murray valley encephalitis virus infection in mosquitoes and domestic fowls in queensland, 1974.field studies during an epidemic of murray valley encephalitis (mve) led to the isolation of mve virus from a pool of mosquitoes (culex annulirostris) and a sentinel chicken from charleville, south-west queensland. a high proportion of domestic fowls at charleville had antibody to mve virus at the beginning of february 1974, in advance of the first case recognized in queensland and allowing early warning from health authorities. a survey of antibody in domestic fowls in mid-1974 suggested widesp ...197613773
a mathematical model for the rural amplification of murray valley encephalitis virus in southern australia.the exacerbation of epidemics of murray valley encephalitis in southern australia during 1951 and 1974 was studied retrospectively to determine when viral introduction may have occurred. data from studies spanning over 30 years were utilized 1) to determine the number of infective culex annulirostris necessary to cause one clinical case, based on known host-feeding patterns and the subclinical infection rate in man, and 2), using mathematical modeling, to calculate the likely duration of the rur ...19873826047
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