Fiji's health ministry is to ask the World Health Organisation to identify the strain of rubella that's broken out in the greater Suva area.
The national advisor for family health in the ministry's public health division says there are 11 confirmed cases but reports of more.
Symptoms of the highly contagious illness, which can cause birth defects or miscarriage, include a mild fever, rash, sore throat and aching joints.
Dr Frances Bingwor says it's not known whether the outbreak began locally or through infection by someone from overseas.
"Which is why we're also keen to genotyping on the samples of the first case, the indexed case and the first few who came and got confirmed. So this is not a test that's done in Fiji. We're in discussions with the World Health Organisation South Pacific office in trying to assist Fiji in getting genotyping first to give a clearer picture on just how the infection started."
Dr Frances Bingwor says Fiji has one of the best rubella immunisation rates in the Pacific, with about 94 percent coverage.