Rubella (German Measles)

Rubella is caused by an enveloped, positive-sense single-stranded RNA virus in the Rubivirus genus of the Togaviridae family. It spreads primarily through respiratory secretions. The incubation period is usually 14–17 days, but may range from 12–21 days. An infected person can transmit the virus from about 7 days before the rash appears until at least 4 days after rash onset, so exposure may occur before anyone recognizes the illness. For most children and adults, rubella is mild or even asymptomatic. Pregnancy changes the priority completely. Maternal viremia can allow the virus to cross the placenta and injure developing fetal tissues during organ formation. Infection in the first trimester carries approximately an 85% risk of fetal infection and congenital rubella syndrome (CRS); the risk falls sharply after 20 weeks of gestation. CRS can involve sensorineural hearing loss, eye disease such as cataracts, congenital heart disease, and later developmental or growth problems. That risk explains why a low-grade maternal fever and a faint rash can demand more urgent action than the mother’s appearance suggests. The nurse is not assessing only how ill...