Viremia and the presence of rubella virus in the throat of infect persons bear which of the following relationships to the onset of the rube rash?

Both viremia and the excretion of virus from the throats of persons infected with rubella occur 5 to 7 days before the appearance of the characteristic maculopapular rash. The importance of this relationship is that by the time a pregnant woman first notes the appearance of a rash on one of her children, she has already been exposed to the disease and may, in fact, be infected. If one member of a family develops rubella, all other members who are susceptible to the disease usually become infected.