Rubella

Rubella is an enveloped positive-sense, single-stranded RNA virus and has recently been reclassified into the Matonaviridae family. Although there is only one serotype of rubella virus, various genotypes exist and identification of these can be used to track outbreaks. Humans are the only reservoir and therefore elimination through vaccination is feasible. The virus is transmitted via respiratory secretions and initially multiplies in the respiratory tract before spreading to other organs and producing a viraemia. At the viraemic stage, the virus can cross the placenta and cause a disseminated infection in the developing foetus. The incubation period, from exposure to rash onset, is 14 days (range 12–23 days), and individuals are infective for approximately 7 days before and 7–12 days after the rash has developed (Best 2007). The virus can be destroyed relatively easily by heat, detergents, extremes of pH or ultraviolet light.