Ross River Virus Activity Along the South Coast of New South Wales

Abstract

Summary. The sera of 468 blood donors and 63 domestic animals, collected from the south coast of New South Wales, were tested for the presence of antibodies to Ross River virus. Antibodies were detected in 7% of human sera, 25% of cow sera and 65% of horse sera. Using the blood donors as 'human sentinels', seroconversions were demonstrated in two donors from the NowraKiama region and from a patient in the same area; none of the three had been outside of the study area during the period of seroconversion or at the time of infection. Ofthe 15 seropositive horses, 6 (40%) had lived continuously since birth on the farms on which they were bled. That humans and horses were infected with Ross River and not a related alphavirus was shown by microneutralization tests against Ross River virus and the other two alphaviruses (Getah, Sindbis) known to occur in Australia.

Sequencing of Historical Isolates, K-mer Mining and High Serological Cross-Reactivity with Ross River Virus Argue against the Presence of Getah Virus in Australia

“…GETV has been isolated in several Asian countries ( Figure 1 ). The contention that GETV also circulates in Australia [ 26 , 27 , 31 , 34 , 35 , 36 ] is based primarily on the isolation of N544 and N554 from mosquitoes trapped in Australia in 1961 [ 24 ]. Both N544 and N554 were stored in the “Doherty Virus Collection”, recently relocated to the QIMR Berghofer Medical Research Institute.…”

“…Early sero-surveillance also identified GETV-reactive antibodies in cattle [ 26 ] and pigs [ 27 ] in Australia using hemagglutination inhibition (HI) assays [ 28 ] to measure anti-viral antibody levels and lethal dose titrations in suckling mice to assess neutralizing antibody levels [ 29 ]. Anti-RRV antibodies have also been detected in cattle and pigs [ 26 , 27 , 30 , 31 , 32 ], with these species also able to be infected experimentally with RRV [ 33 ]. Early serosurveys [ 26 , 27 ] frequently found sera that reacted with both RRV and GETV.…”

“…Nevertheless, in these studies (i) 22 out of 1389 serum samples from cattle reacted with GETV (but not RRV) by HI, with 4 showing anti-GETV neutralizing activity [ 26 ] and (ii) out of 239 pig sera, 4 reacted with GETV (but not RRV) by HI and 1 of these neutralized only GETV [ 27 ]. Together with isolation of N554 and N544, these serosurveys [ 26 , 27 ] have led to the established view that GETV circulates in Australia [ 31 , 34 , 35 , 36 ], with multiple papers and reviews including Australia in the list of countries where GETV circulates [ 37 , 38 , 39 ].…”

Seroprevalence and associated risk factors of mosquito‐borne alphaviruses in horses in northern Queensland

“…RRV is endemic in Australia and is the most common vector‐borne disease in humans, accounting for 56% of the total notifications in an annual report of the National Notifiable Diseases Surveillance System . Infection by RRV in horses is also significant, with seroprevalence reported at 56% in one study of Victorian horses suspected to have contracted the disease and in 65% of horses involved in a serological survey in New South Wales …”

Invasive carcinoma of the cervix in young women

“…This trend has occurred in spite of evidence that it is the same birth cohort of women who are most exposed to and use cervical cytology services. 8,9 This study was prompted by a clinical impression that increasing numbers of young women were presenting with invasive cancer who had had recently a negative result of cytological examination. The aim of this paper was to investigate a group of such women by examining their cytological smears and symptom histories.…”