Ross River virus (RRV)

The donor developed an illness clinically compatible with RRV infection 2 days after donating blood and was shown to have a serological profile consistent with acute RRV infection 10 days after donating. The donated blood was subsequently shown to contain RRV RNA by two in-house RT-PCR tests, and this was confirmed by sequencing. While the exacerbation of the chronically ill recipient’s fatigue and muscle and joint pains was not clearly consistent with the incubation period of RRV subsequent to the transfusion, the results of RRV serological tests performed about 2 months after transfusion were consistent with infection within this 2-month period. There were no stored blood specimens collected from the recipient shortly after receiving the blood donation, and hence it was not possible to compare sequences with the donor virus to confirm transmission. Surveillance by the WA Department of Health showed that the recipient was the only person for whom RRV infection was reported between 1 July 2013 and 30 June 2014 from the local government area in which she resided. The recipient also spent most of her time indoors and could not recall being bitten by mosquitoes. Taken together, these lines of evidence strongly support the likelihood that the recipient’s RRV infection was transmitted by transfusion.