Does ross river fever virus show in blood tests for the rest of your life?

For a long time: The immune response to ross fever virus is detectable as a rising level of antibodies to the virus. Those antibodies persist in the blood, usually for decades. After a long time, the antibody titer (amount of antibody) in the blood will fall to below detectable levels in some people. Most will still have detectable antibodies in the blood for their entire lives.